You are using an out of date browser. It may not display this or other websites correctly.
You should upgrade or use an alternative browser.
You should upgrade or use an alternative browser.
Export thread
The Reason I think Synthetic Oil is Best for 4-Cycle Mower Engines. "Who Agrees?"
#1
R
RoofTopPigeon
R
RoofTopPigeon
The Reason I think Synthetic Oil is Best for 4-Cycle Mower Engines. "Who Agrees?"
I feel that the Full-Synthetic With "MaxLife" Technology (or) a Similar Synthetic is the ONLY Logical Choice for "4-Cycle" push mower engines.
The Reason I feel this way: Is because it says on the bottle that it's made for older engines with running temps over 400ºF.
And Because Push Mower Engines are air-cooled and don't have radiators they typically run a tad hotter then car engines anyway
between 220ºF and 250ºF on average give or take a little. Most Mower Manufactures Recommend a SAE-30;
However My Briggs And Stratton Engine allows me to use a Synthetic 5W-30 (i.e. small engine manufactures vary)
So I plan to always use Valvoline High Mileage Full-Synthetic Max Life 5W-30 in my personal mower because it allows for it.
Lastly;
Most Full-Synthetic Motor Oils are said to be capable of protecting an engine “at well over 400ºF" degrees;
However; in the real world, most Nascar Teams and other Motor-Sports Racers have
NO problem running Full-Synthetic Oil's up to 290ºF degrees under prolonged Track Use;
However they do tend to get really Jumpy... When a Conventional exceeds 270ºF.
I feel that the Full-Synthetic With "MaxLife" Technology (or) a Similar Synthetic is the ONLY Logical Choice for "4-Cycle" push mower engines.
The Reason I feel this way: Is because it says on the bottle that it's made for older engines with running temps over 400ºF.
And Because Push Mower Engines are air-cooled and don't have radiators they typically run a tad hotter then car engines anyway
between 220ºF and 250ºF on average give or take a little. Most Mower Manufactures Recommend a SAE-30;
However My Briggs And Stratton Engine allows me to use a Synthetic 5W-30 (i.e. small engine manufactures vary)
So I plan to always use Valvoline High Mileage Full-Synthetic Max Life 5W-30 in my personal mower because it allows for it.
Lastly;
Most Full-Synthetic Motor Oils are said to be capable of protecting an engine “at well over 400ºF" degrees;
However; in the real world, most Nascar Teams and other Motor-Sports Racers have
NO problem running Full-Synthetic Oil's up to 290ºF degrees under prolonged Track Use;
However they do tend to get really Jumpy... When a Conventional exceeds 270ºF.
Attachments
#2
7394
7394
Re: The Reason I think Synthetic Oil is Best for 4-Cycle Mower Engines. "Who Agrees?"
Whatever ya run, I'd stay away from hi-mileage oils. They have additives to swell oil seals & after time the seals can become brittle & leak.
Sounds like you have a newer push mow.
Whatever ya run, I'd stay away from hi-mileage oils. They have additives to swell oil seals & after time the seals can become brittle & leak.
Sounds like you have a newer push mow.
#3
B
bertsmobile1
B
bertsmobile1
Re: The Reason I think Synthetic Oil is Best for 4-Cycle Mower Engines. "Who Agrees?"
If it makes you feel good, then do it.
There is little advantage in using a synthetic oil in most mowers with a carb on them.
EFI is a bit different.
just remember what gets used in a race car on a race track where it gets changed at the end of every track day if not every race might not be what an air cooled engine that sits for 4 months a year actually needs .
While overall oil temperature stability is important, being able to withstand very short term exposure to very high temperatures is more important still.
As is overall performance over a wide range of operating temperature.
In a car, even a top fuel NASCAR drag racer, the engine temperature is controlled by the water jacket and remains very constant.
In an air cooled mower engine temperatures are all over the kitchen.
And lastly, what MEN in particularly seem to forget.
Its only a bloody lawnmower, built to lawnmower specifications & internal clearences.
OTOH it is YOUR lawnmower so if it makes you feel good then do it.
Why do I feel it is a waste of time & money ?
All the mowers I service that get an oil change once every blue moon and come in with oil that thick I have to dilute it to drain it out then go on and do another 500 trouble free hours before I put my hands on them again on a belly full of SAE 30
If it makes you feel good, then do it.
There is little advantage in using a synthetic oil in most mowers with a carb on them.
EFI is a bit different.
just remember what gets used in a race car on a race track where it gets changed at the end of every track day if not every race might not be what an air cooled engine that sits for 4 months a year actually needs .
While overall oil temperature stability is important, being able to withstand very short term exposure to very high temperatures is more important still.
As is overall performance over a wide range of operating temperature.
In a car, even a top fuel NASCAR drag racer, the engine temperature is controlled by the water jacket and remains very constant.
In an air cooled mower engine temperatures are all over the kitchen.
And lastly, what MEN in particularly seem to forget.
Its only a bloody lawnmower, built to lawnmower specifications & internal clearences.
OTOH it is YOUR lawnmower so if it makes you feel good then do it.
Why do I feel it is a waste of time & money ?
All the mowers I service that get an oil change once every blue moon and come in with oil that thick I have to dilute it to drain it out then go on and do another 500 trouble free hours before I put my hands on them again on a belly full of SAE 30
#4
R
RoofTopPigeon
R
RoofTopPigeon
Re: The Reason I think Synthetic Oil is Best for 4-Cycle Mower Engines. "Who Agrees?"
bertsmobile1; isn't it true that Synthetic's Hold-up longer in the heat?
I have also read that Most Race Drivers have NO problem running
Full-Synthetic Oil up to 290ºF degrees under prolonged Track Use;
However they do tend to get really Jumpy... When a Conventional exceeds 270ºF.
Why do I feel it is a waste of time & money ?
All the mowers I service that get an oil change once every blue moon and come in with oil that thick I have to dilute it to drain it out then go on and do another 500 trouble free hours before I put my hands on them again on a belly full of SAE 30
bertsmobile1; isn't it true that Synthetic's Hold-up longer in the heat?
I have also read that Most Race Drivers have NO problem running
Full-Synthetic Oil up to 290ºF degrees under prolonged Track Use;
However they do tend to get really Jumpy... When a Conventional exceeds 270ºF.
#5
B
bertsmobile1
B
bertsmobile1
Re: The Reason I think Synthetic Oil is Best for 4-Cycle Mower Engines. "Who Agrees?"
I am really tempted to quote from "a Fish Called Wanda" about monkeys reading philosophy.
But I will put it this way.
There are fully synthetic oils that have been developed for lawn mower use.
There are fully synthetic oils that have been developed for NASCAR use.
Which bit of NASCAR technology is relevant to lawnmowers and why is it relevant ?
How do "extra miles" equate to operating hours ?
What are the operating temperatures inside your engine , any idea?
Where were the operating temperatures of 290 F measured ?
In the sump, in the head , around the red hot exhaust valve ?
Race car drivers run on slick tyres, does that mean you should go and grind the tread off your car tyres to make it handle better ?
In a mower engine if a conventional oil ever gets to the thermal break down temperature then the engine is already trashed so what advantage do you gain from having an oil in there that can go 10% higher ?
The only time conventional oils usually go beyond their temperature limit is when there is not enough oil in there and again the engine will be trashed.
There is one and only one advantage to running a synthetic in a mower.
Synthetics have a lower viscious friction so at cranking speeds will offer slightly ( and I mean very slightly ) lower resistance to cranking so an engine with 20 times the valve lash it should have and thus no decompression, might just spin fast enough to start.
To gain the advantages that synthetic oils can offer, and I will not arge that they do offer advantages,
THE ENGINE HAS TO BE DESIGNED TO USE THEM
Otherwise you are wasting money.
I would liken it to your buying a pair of $ 3000 state of the art running shoes in a size too big for your feet then expecting them to propel you to a victory in the Boston Marathon.
Further more at $ 5 a time very few care how often they change their oils so mid season at the recommended hours then at the end of season, only at 1/3 the hours, no problems.
But when the oil is $ 20 and supposed to last 3 times as long no one wants to change it at the most important time.
Before the engine is laid up over winter.
Synthetic or non synthetic, sitting in the sump for 4 months going nowhere and gravity will do its dirty work and deposit all of the heavy nasties that were suspended in the oil into the lower bush and all of the lighter acidic nasties will float to the top doing their best to turn your engine into scrap metal.
This efect is worse in synthetics than std oils because they are freer draining
But again, it is a free world and if it makes you feel good having NASCAR grade oil in your mower, buy a bottle, shove it in get a sticker for the side and feel good about it.
I have also read that Most Race Drivers have NO problem running
Full-Synthetic Oil up to 290ºF degrees under prolonged Track Use;
However they do tend to get really Jumpy... When a Conventional exceeds 270ºF.
I am really tempted to quote from "a Fish Called Wanda" about monkeys reading philosophy.
But I will put it this way.
There are fully synthetic oils that have been developed for lawn mower use.
There are fully synthetic oils that have been developed for NASCAR use.
Which bit of NASCAR technology is relevant to lawnmowers and why is it relevant ?
How do "extra miles" equate to operating hours ?
What are the operating temperatures inside your engine , any idea?
Where were the operating temperatures of 290 F measured ?
In the sump, in the head , around the red hot exhaust valve ?
Race car drivers run on slick tyres, does that mean you should go and grind the tread off your car tyres to make it handle better ?
In a mower engine if a conventional oil ever gets to the thermal break down temperature then the engine is already trashed so what advantage do you gain from having an oil in there that can go 10% higher ?
The only time conventional oils usually go beyond their temperature limit is when there is not enough oil in there and again the engine will be trashed.
There is one and only one advantage to running a synthetic in a mower.
Synthetics have a lower viscious friction so at cranking speeds will offer slightly ( and I mean very slightly ) lower resistance to cranking so an engine with 20 times the valve lash it should have and thus no decompression, might just spin fast enough to start.
To gain the advantages that synthetic oils can offer, and I will not arge that they do offer advantages,
THE ENGINE HAS TO BE DESIGNED TO USE THEM
Otherwise you are wasting money.
I would liken it to your buying a pair of $ 3000 state of the art running shoes in a size too big for your feet then expecting them to propel you to a victory in the Boston Marathon.
Further more at $ 5 a time very few care how often they change their oils so mid season at the recommended hours then at the end of season, only at 1/3 the hours, no problems.
But when the oil is $ 20 and supposed to last 3 times as long no one wants to change it at the most important time.
Before the engine is laid up over winter.
Synthetic or non synthetic, sitting in the sump for 4 months going nowhere and gravity will do its dirty work and deposit all of the heavy nasties that were suspended in the oil into the lower bush and all of the lighter acidic nasties will float to the top doing their best to turn your engine into scrap metal.
This efect is worse in synthetics than std oils because they are freer draining
But again, it is a free world and if it makes you feel good having NASCAR grade oil in your mower, buy a bottle, shove it in get a sticker for the side and feel good about it.
#6
R
RoofTopPigeon
R
RoofTopPigeon
Re: The Reason I think Synthetic Oil is Best for 4-Cycle Mower Engines. "Who Agrees?"
Briggs and Stratton Engine owner asked:
“Should I use synthetic or conventional (regular) oil in my 4-Cycle Briggs & Stratton Engine?
Brigg and Stratton Answered:
Our engines are designed to run on conventional oil, full synthetic, or synthetic blends. It’s an owner’s personal decision if the extra cost is worth the additional benefits synthetic oils offer. When a customer calls the Answer Center, we recommend the synthetic as it offers the premium protections we talked about earlier.
My Source: http://blog.briggsandstratton.com/s...oil-what-do-i-use-in-my-small-4-cycle-engine/
Bertsmobile1; So there you have it; since the engine on my mower is a Briggs and Stratton it is capable of and designed to run on Synthetic!
THE ENGINE HAS TO BE DESIGNED TO USE THEM
Otherwise you are wasting money.
Briggs and Stratton Engine owner asked:
“Should I use synthetic or conventional (regular) oil in my 4-Cycle Briggs & Stratton Engine?
Brigg and Stratton Answered:
Our engines are designed to run on conventional oil, full synthetic, or synthetic blends. It’s an owner’s personal decision if the extra cost is worth the additional benefits synthetic oils offer. When a customer calls the Answer Center, we recommend the synthetic as it offers the premium protections we talked about earlier.
My Source: http://blog.briggsandstratton.com/s...oil-what-do-i-use-in-my-small-4-cycle-engine/
Bertsmobile1; So there you have it; since the engine on my mower is a Briggs and Stratton it is capable of and designed to run on Synthetic!
#7
R
RoofTopPigeon
R
RoofTopPigeon
Re: The Reason I think Synthetic Oil is Best for 4-Cycle Mower Engines. "Who Agrees?"
Briggs and Stratton Engine owner asked:
“Should I use synthetic or conventional (regular) oil in my 4-Cycle Briggs & Stratton Engine?
Brigg and Stratton Answered:
Our engines are designed to run on conventional oil, full synthetic, or synthetic blends.
It’s an owner’s personal decision if the extra cost is worth the additional benefits synthetic oils offer.
When a customer calls the Answer Center, we recommend the synthetic as it offers the premium protections we talked about earlier.
My Source: http://blog.briggsandstratton.com/s...oil-what-do-i-use-in-my-small-4-cycle-engine/
Bertsmobile1; So there you have it; since the engine on my mower is a Briggs and Stratton it is capable of and designed to run on Synthetic!
and they also provide this chart
with the stipulations that
1.) Running an 10w-30 in outside temps over 80ºF may cause increased oil consumption
2.) Running an SAE-30 in Temps below 40ºF may cause hard starting.
This is why I chose to go with the Synthetic 5w-30 of the options recommended in the Manual
THE ENGINE HAS TO BE DESIGNED TO USE THEM
Otherwise you are wasting money.
Briggs and Stratton Engine owner asked:
“Should I use synthetic or conventional (regular) oil in my 4-Cycle Briggs & Stratton Engine?
Brigg and Stratton Answered:
Our engines are designed to run on conventional oil, full synthetic, or synthetic blends.
It’s an owner’s personal decision if the extra cost is worth the additional benefits synthetic oils offer.
When a customer calls the Answer Center, we recommend the synthetic as it offers the premium protections we talked about earlier.
My Source: http://blog.briggsandstratton.com/s...oil-what-do-i-use-in-my-small-4-cycle-engine/
Bertsmobile1; So there you have it; since the engine on my mower is a Briggs and Stratton it is capable of and designed to run on Synthetic!
and they also provide this chart
with the stipulations that
1.) Running an 10w-30 in outside temps over 80ºF may cause increased oil consumption
2.) Running an SAE-30 in Temps below 40ºF may cause hard starting.
This is why I chose to go with the Synthetic 5w-30 of the options recommended in the Manual
#8
R
RoofTopPigeon
R
RoofTopPigeon
Re: The Reason I think Synthetic Oil is Best for 4-Cycle Mower Engines. "Who Agrees?"
Briggs and Stratton Engine owner asked:
“Should I use synthetic or conventional (regular) oil in my 4-Cycle Briggs & Stratton Engine?
Brigg and Stratton Answered:
Our engines are designed to run on conventional oil, full synthetic, or synthetic blends.
It’s an owner’s personal decision if the extra cost is worth the additional benefits synthetic oils offer.
When a customer calls the Answer Center, we recommend the synthetic as it offers the premium protections we talked about earlier.
My Source: http://blog.briggsandstratton.com/s...oil-what-do-i-use-in-my-small-4-cycle-engine/
Bertsmobile1; So there you have it; since the engine on my mower is a Briggs and Stratton it is capable of and designed to run on Synthetic!
and they also provide this chart
with the stipulations that
1.) Running an 10w-30 in outside temps over 80ºF may cause increased oil consumption
2.) Running an SAE-30 in Temps below 40ºF may cause hard starting.
This is why I chose to go with the Synthetic 5w-30 of the options recommended in the Manual
and I figure since Valvoline Full-Synthetic meets the Latest "SN" oil Standard; it should be good enough for my mower.
View attachment 30407
THE ENGINE HAS TO BE DESIGNED TO USE THEM
Otherwise you are wasting money.
Briggs and Stratton Engine owner asked:
“Should I use synthetic or conventional (regular) oil in my 4-Cycle Briggs & Stratton Engine?
Brigg and Stratton Answered:
Our engines are designed to run on conventional oil, full synthetic, or synthetic blends.
It’s an owner’s personal decision if the extra cost is worth the additional benefits synthetic oils offer.
When a customer calls the Answer Center, we recommend the synthetic as it offers the premium protections we talked about earlier.
My Source: http://blog.briggsandstratton.com/s...oil-what-do-i-use-in-my-small-4-cycle-engine/
Bertsmobile1; So there you have it; since the engine on my mower is a Briggs and Stratton it is capable of and designed to run on Synthetic!
and they also provide this chart
with the stipulations that
1.) Running an 10w-30 in outside temps over 80ºF may cause increased oil consumption
2.) Running an SAE-30 in Temps below 40ºF may cause hard starting.
This is why I chose to go with the Synthetic 5w-30 of the options recommended in the Manual
and I figure since Valvoline Full-Synthetic meets the Latest "SN" oil Standard; it should be good enough for my mower.
View attachment 30407
#9
S
sidemouse
S
sidemouse
Re: The Reason I think Synthetic Oil is Best for 4-Cycle Mower Engines. "Who Agrees?"
Quite simply put full synthetic is the best oil out there.
I run it in everything except 2-cyclers and boat engines, same grade too.
One oil for all 4-cyclers, simplifies life a lot.
In my case it happens to be 5w-20.
I put it in my car, truck, motorcycle, mowers, push blower, aerator, tiller, you name it.
Been doing it for a good many years.
Quite simply put full synthetic is the best oil out there.
I run it in everything except 2-cyclers and boat engines, same grade too.
One oil for all 4-cyclers, simplifies life a lot.
In my case it happens to be 5w-20.
I put it in my car, truck, motorcycle, mowers, push blower, aerator, tiller, you name it.
Been doing it for a good many years.
#10
R
RoofTopPigeon
R
RoofTopPigeon
Re: The Reason I think Synthetic Oil is Best for 4-Cycle Mower Engines. "Who Agrees?"
Briggs and Stratton Engine owner asked:
“Should I use synthetic or conventional (regular) oil in my 4-Cycle Briggs & Stratton Engine?
Brigg and Stratton Answered:
Our engines are designed to run on conventional oil, full synthetic, or synthetic blends.
It’s an owner’s personal decision if the extra cost is worth the additional benefits synthetic oils offer.
When a customer calls the Answer Center, we recommend the synthetic as it offers the premium protections we talked about earlier.
My Source: http://blog.briggsandstratton.com/s...oil-what-do-i-use-in-my-small-4-cycle-engine/
Bertsmobile1; So there you have it; since the engine on my mower is a Briggs and Stratton it is capable of and designed to run on Synthetic!
and they also provide this chart:
with the stipulations that
1.) Running an 10w-30 in outside temps over 80ºF may cause increased oil consumption
2.) Running an SAE-30 in Temps below 40ºF may cause hard starting.
This is why I chose to go with the Synthetic 5w-30 of the options recommended in the Manual
and I figure since Valvoline Full-Synthetic meets the Latest "SN" oil Standard; it should be good enough for my mower.
View attachment 30407
THE ENGINE HAS TO BE DESIGNED TO USE THEM
Otherwise you are wasting money.
Briggs and Stratton Engine owner asked:
“Should I use synthetic or conventional (regular) oil in my 4-Cycle Briggs & Stratton Engine?
Brigg and Stratton Answered:
Our engines are designed to run on conventional oil, full synthetic, or synthetic blends.
It’s an owner’s personal decision if the extra cost is worth the additional benefits synthetic oils offer.
When a customer calls the Answer Center, we recommend the synthetic as it offers the premium protections we talked about earlier.
My Source: http://blog.briggsandstratton.com/s...oil-what-do-i-use-in-my-small-4-cycle-engine/
Bertsmobile1; So there you have it; since the engine on my mower is a Briggs and Stratton it is capable of and designed to run on Synthetic!
and they also provide this chart:
with the stipulations that
1.) Running an 10w-30 in outside temps over 80ºF may cause increased oil consumption
2.) Running an SAE-30 in Temps below 40ºF may cause hard starting.
This is why I chose to go with the Synthetic 5w-30 of the options recommended in the Manual
and I figure since Valvoline Full-Synthetic meets the Latest "SN" oil Standard; it should be good enough for my mower.
View attachment 30407
#11
B
bertsmobile1
B
bertsmobile1
Re: The Reason I think Synthetic Oil is Best for 4-Cycle Mower Engines. "Who Agrees?"
If you had the slightest understanding about oils Lubrication & engine design it would be abundantly clear that if an engine will run on conventional oil it has not been designed to utilise the full potential of synthetic oils.
The closest analogy is filling your old WWII side valve engine with 100 Octane racing fuel when it will happily run on 75 wartime pool petrol.
It will chug along on hi-test gas but it won't make 1 rpm more than it did on 75 and cost more to run.
It will require less downtime scraping carbon off the piston crown but it won't run any better.
Did Briggs say to run the synthetic for 2 or 3 times longer than conventional oils ?
IF not then what advantage are you gaining ?
The cooling of the engine is a function of the heat transfer surfaces and the R value at the interface between the hot metal & the cooling medium.
Oil is a poor conductor of heat so at best will transfer some heat from the hot head & cylinder down to the sump where the action of the flywheel & counter weight will actually increase the heat and because the sump is out of the cooling air flow and most times shielded by the bottom of the mower floor the rate of heat loss is very low.
Now unlike your NASCAR, the primary method of lubrication inside your mower engine is splash.
So while the NASCAR engine throws fairly clean oil out off the big end up into the cylinder, and all bearing run in cleaner filtered oil, your engine splashes the dirty oil sitting in the sump up the cylinder walls.
The bottom bush runs in the same dirty oil , along with any grit, carbon particles , acid combustion by-products and dust sucked inside.
On a lot of engines the upper bush also is splash lubricated and it is only the oil that is actually pressure fed into the big end that is filtered and that only happens on engines that actually have oil filters, which is not as many as you would think.
AFAIK the only mower engine with full pressure fed lubrication currently in production are the Kawakasi ones which is one reason why they are $ 500 + more expensive than the Kohlers.
Even then , there is no seal between the crankshaft and the sump so the lower bush still runs in the dirty sump oil
Now for some of the contractors who have no choice but to mow 25 deg or 100 deg and do 300 + hours a year, then there is an advantage which makes it worthwhile.
As for Joe Blow home owner it will not make the slightest bit of difference apart from making them think their manly protuberance is bigger than the bloke next door.
For many many many years I have been advising motorcycle owners that the best oil for their vintage engine is the stuff they just drained out at a shorter interval than recommended.
I run 100 year old engines on Gulf Western ( local blender ) 25w75 at $ 3.95/ litre ( ~ 1 quart) and I never have any oil related engine problems.
Because it is cheap I change it every time I use the motorcycle, just before I put it away.
Born again motorcyclists buy really expensive ( sometimes synthetic ) oil then expect it to last 20 years because they only ride it 200 miles a year.
I pass their pretty polished catalogue correct bikes on the break down trailers regularly.
Then there are the fools who try to run full synthetic only to find it will not make an effective seal between the rings & the psiston and because it is subdstantially slipperier than std oils actually prevents the piston rings bedded into the cylinder walls.
The post WW II motorcycles get SAE 30 mower oil which I buy for $ 2.45 / litre and same story, get home, drain the oil refill and the bike is ready for the next outing and I do about 30,000 miles on these bikes per year.
99.999999999999999999999999999999999999999999999999999999999999999999999999999999999999999% of the oil related problem that come into the workshop is because the owner has not checked the oil and there wasn't any.
Even then very few of them had fully cooked oil, some was a bit thick due to high concentrations of particulate matter, but not cooked.
Now if you really want to know, search the forum for "engine temperatures".
While not particularly good, nor done properly a list member did at least make a reasonable effort to plot engine temperatures over a variety of operating conditions & ambient temperatures.
These were all surface temperatures which will have to be extrapolated to get interiour temperatures but not too bad and from memory he did some oil sump temperatures as well.
Do this enough & you can make tables which are useful.
At temperatures above 250 deg F the alloy used in the cylinder head starts to soften which allows bolts to loosen and valve guides to slip so having an oil in there that is stable above this temperature is totally useless.
But as stated before.
If it makes you feel good, do it. It is your mower & your money
If you had the slightest understanding about oils Lubrication & engine design it would be abundantly clear that if an engine will run on conventional oil it has not been designed to utilise the full potential of synthetic oils.
The closest analogy is filling your old WWII side valve engine with 100 Octane racing fuel when it will happily run on 75 wartime pool petrol.
It will chug along on hi-test gas but it won't make 1 rpm more than it did on 75 and cost more to run.
It will require less downtime scraping carbon off the piston crown but it won't run any better.
Did Briggs say to run the synthetic for 2 or 3 times longer than conventional oils ?
IF not then what advantage are you gaining ?
The cooling of the engine is a function of the heat transfer surfaces and the R value at the interface between the hot metal & the cooling medium.
Oil is a poor conductor of heat so at best will transfer some heat from the hot head & cylinder down to the sump where the action of the flywheel & counter weight will actually increase the heat and because the sump is out of the cooling air flow and most times shielded by the bottom of the mower floor the rate of heat loss is very low.
Now unlike your NASCAR, the primary method of lubrication inside your mower engine is splash.
So while the NASCAR engine throws fairly clean oil out off the big end up into the cylinder, and all bearing run in cleaner filtered oil, your engine splashes the dirty oil sitting in the sump up the cylinder walls.
The bottom bush runs in the same dirty oil , along with any grit, carbon particles , acid combustion by-products and dust sucked inside.
On a lot of engines the upper bush also is splash lubricated and it is only the oil that is actually pressure fed into the big end that is filtered and that only happens on engines that actually have oil filters, which is not as many as you would think.
AFAIK the only mower engine with full pressure fed lubrication currently in production are the Kawakasi ones which is one reason why they are $ 500 + more expensive than the Kohlers.
Even then , there is no seal between the crankshaft and the sump so the lower bush still runs in the dirty sump oil
Now for some of the contractors who have no choice but to mow 25 deg or 100 deg and do 300 + hours a year, then there is an advantage which makes it worthwhile.
As for Joe Blow home owner it will not make the slightest bit of difference apart from making them think their manly protuberance is bigger than the bloke next door.
For many many many years I have been advising motorcycle owners that the best oil for their vintage engine is the stuff they just drained out at a shorter interval than recommended.
I run 100 year old engines on Gulf Western ( local blender ) 25w75 at $ 3.95/ litre ( ~ 1 quart) and I never have any oil related engine problems.
Because it is cheap I change it every time I use the motorcycle, just before I put it away.
Born again motorcyclists buy really expensive ( sometimes synthetic ) oil then expect it to last 20 years because they only ride it 200 miles a year.
I pass their pretty polished catalogue correct bikes on the break down trailers regularly.
Then there are the fools who try to run full synthetic only to find it will not make an effective seal between the rings & the psiston and because it is subdstantially slipperier than std oils actually prevents the piston rings bedded into the cylinder walls.
The post WW II motorcycles get SAE 30 mower oil which I buy for $ 2.45 / litre and same story, get home, drain the oil refill and the bike is ready for the next outing and I do about 30,000 miles on these bikes per year.
99.999999999999999999999999999999999999999999999999999999999999999999999999999999999999999% of the oil related problem that come into the workshop is because the owner has not checked the oil and there wasn't any.
Even then very few of them had fully cooked oil, some was a bit thick due to high concentrations of particulate matter, but not cooked.
Now if you really want to know, search the forum for "engine temperatures".
While not particularly good, nor done properly a list member did at least make a reasonable effort to plot engine temperatures over a variety of operating conditions & ambient temperatures.
These were all surface temperatures which will have to be extrapolated to get interiour temperatures but not too bad and from memory he did some oil sump temperatures as well.
Do this enough & you can make tables which are useful.
At temperatures above 250 deg F the alloy used in the cylinder head starts to soften which allows bolts to loosen and valve guides to slip so having an oil in there that is stable above this temperature is totally useless.
But as stated before.
If it makes you feel good, do it. It is your mower & your money
#12
M
mrstan
M
mrstan
Re: The Reason I think Synthetic Oil is Best for 4-Cycle Mower Engines. "Who Agrees?"
Hi guys,
I looked into this topic when I was replacing my car's oil as well. What I found was that the synthetic molecules are smaller than the conventional molecules. for this reason, the oil manufacturers were answering questions related to blow-by and oil consumption regarding full synthetics. What I took away from the discussions was that the synthetic oil can get into places where conventional oil
simply can not fit. This comes into plat when you have an engine with very tight tolerances in the journals and passages. The major line of the discussion revolved around the assertion of leaks caused by the synthetics which did not happen with conventional. Newer auto engines hold tighter tolerances obviously as you can see their oil change cycles are extended to 7000 miles is many instances... Compression is heightened by the same tolerances in the rings as well.
with this as background, my outtake was that lubrication is heightened because of the smaller mechanics of the molecules for sure, but care must be taken to avert the leaks since it can seep out of smaller fissures. I am not sure of the journal tolerances on a lawnmower engine are exactly, but I would assume they might be somewhat wide (will have to look mine up as well).
As to the temperature of lawnmower engines, I think it should be around 250F typically. Remember Gasoline flashes at 536F, so we do not want the engines to get around 400 like I saw in some post earlier was suggesting.
Car engines typically run around 220 to 240F, but they are normally water-cooled where the lawnmowers generally rely on airflow to draw heat away. The heat characteristics of the oil should be around the same as a typical automotive engine in other words.
I do not know how to really determine if synthetic is better than conventional in the small engine world because lubrication is done with a smaller amount with smaller components (This is why we have to change the oil so much more often too). I read where synthetic oil dissipates heat more readily than conventional, but also that it oxidizes faster as well. IS the quantification of significance though? I do not know any numbers or even if this has been actually tested clinically. In my opinion, its a lawn mower... LOL Just use best judgement I guess. Maybe someday someone with lots of time on their hands will actually study this stuff all out.
Hi guys,
I looked into this topic when I was replacing my car's oil as well. What I found was that the synthetic molecules are smaller than the conventional molecules. for this reason, the oil manufacturers were answering questions related to blow-by and oil consumption regarding full synthetics. What I took away from the discussions was that the synthetic oil can get into places where conventional oil
simply can not fit. This comes into plat when you have an engine with very tight tolerances in the journals and passages. The major line of the discussion revolved around the assertion of leaks caused by the synthetics which did not happen with conventional. Newer auto engines hold tighter tolerances obviously as you can see their oil change cycles are extended to 7000 miles is many instances... Compression is heightened by the same tolerances in the rings as well.
with this as background, my outtake was that lubrication is heightened because of the smaller mechanics of the molecules for sure, but care must be taken to avert the leaks since it can seep out of smaller fissures. I am not sure of the journal tolerances on a lawnmower engine are exactly, but I would assume they might be somewhat wide (will have to look mine up as well).
As to the temperature of lawnmower engines, I think it should be around 250F typically. Remember Gasoline flashes at 536F, so we do not want the engines to get around 400 like I saw in some post earlier was suggesting.
Car engines typically run around 220 to 240F, but they are normally water-cooled where the lawnmowers generally rely on airflow to draw heat away. The heat characteristics of the oil should be around the same as a typical automotive engine in other words.
I do not know how to really determine if synthetic is better than conventional in the small engine world because lubrication is done with a smaller amount with smaller components (This is why we have to change the oil so much more often too). I read where synthetic oil dissipates heat more readily than conventional, but also that it oxidizes faster as well. IS the quantification of significance though? I do not know any numbers or even if this has been actually tested clinically. In my opinion, its a lawn mower... LOL Just use best judgement I guess. Maybe someday someone with lots of time on their hands will actually study this stuff all out.
#13
B
bertsmobile1
B
bertsmobile1
Re: The Reason I think Synthetic Oil is Best for 4-Cycle Mower Engines. "Who Agrees?"
Just so we all know what we are talking about here.
Synthetic oils are not synthetic.
They are not some magic conerting water into oil.
All synthetics are is an extension of what we already do with hundreds of products.
In place of refining oil to make a particular grade or product, we take it apart then add the bits we want back together.
It originated in Europe so they could use their high ash crude.
We do the same thing with wheat, corn, barley and milk,
Depending upon how far it was taken apart determines weather it gets called Fully or Semi Synthetic.
To utilise full synthetic oils the piston ring side clearence has to be reduced to almost nothing, otherwise it can not form a seal between the ring & the ring grove and the engine will leak compression.
There are a lot of other examples but that is the one which will make most sense to those without a fuller understanding of engine design & lubrication.
Low ash synthetics are great for 2 strokes as they disperse better in the fuel and condense back into oil better in the crank case, they are more slippery ( because we control the size & shape of the molocules ) so can be used in far mre dilute concentrations so we have low smoke low ash 2 strokes, brilliant, except the EPA's in almost every country are bending over backward to ban 2 strokes.
Just so we all know what we are talking about here.
Synthetic oils are not synthetic.
They are not some magic conerting water into oil.
All synthetics are is an extension of what we already do with hundreds of products.
In place of refining oil to make a particular grade or product, we take it apart then add the bits we want back together.
It originated in Europe so they could use their high ash crude.
We do the same thing with wheat, corn, barley and milk,
Depending upon how far it was taken apart determines weather it gets called Fully or Semi Synthetic.
To utilise full synthetic oils the piston ring side clearence has to be reduced to almost nothing, otherwise it can not form a seal between the ring & the ring grove and the engine will leak compression.
There are a lot of other examples but that is the one which will make most sense to those without a fuller understanding of engine design & lubrication.
Low ash synthetics are great for 2 strokes as they disperse better in the fuel and condense back into oil better in the crank case, they are more slippery ( because we control the size & shape of the molocules ) so can be used in far mre dilute concentrations so we have low smoke low ash 2 strokes, brilliant, except the EPA's in almost every country are bending over backward to ban 2 strokes.
#14
R
RoofTopPigeon
R
RoofTopPigeon
Re: The Reason I think Synthetic Oil is Best for 4-Cycle Mower Engines. "Who Agrees?"
bertsmobile1; what do you feel is best for 4-cycle engines then?
For 4-Cycle's would you just go with the manufacture recommendation?
Low ash synthetics are great for 2 strokes as they disperse better in the fuel and condense back into oil better in the crank case, they are more slippery ( because we control the size & shape of the molocules ) so can be used in far mre dilute concentrations so we have low smoke low ash 2 strokes, brilliant, except the EPA's in almost every country are bending over backward to ban 2 strokes.
bertsmobile1; what do you feel is best for 4-cycle engines then?
For 4-Cycle's would you just go with the manufacture recommendation?
#15
B
bertsmobile1
B
bertsmobile1
Re: The Reason I think Synthetic Oil is Best for 4-Cycle Mower Engines. "Who Agrees?"
It depends upon the engine.
Side bangers all get strait SAE 30 mower oil
Honda walk behinds get 10W 30 mower oil for residential customers & 10W 40 for commercial customers.
late model kawakasi get 10W 40
All carby Kohlers apart from those under warranty get SAE 30
EFI Kohlers get 10W 40
Inteks get SAE 10w 30.
All of these a standard LAWN Mower oils
You see there is no such thing as the best oil for all.
I keep 5 gal of fully synthetic 5W 40 mower oil because 1 customer wants me to use it but he still gets his oil changes done at the same hours a if it was std oil and he pays $ 55 / litre.
He likes it because he is impatient and the mower fires up before the ignition key gets to the end of the rotation.
I go through 4 x 44's of 30 for every 44 of 10W 40 and 2 of those for each 10w 30.
Climate here is similar to Southern California and we mow all year round.
Synthetics are really a con but to comply with emissions at start up laws car companies specify them rather than modifing their engines.
That way you pay & they don't
OTOH the synthetic gear oils are a different kettle of fish, worth every extra cent but then Joe Average would only change the gearbox &/or diff oil once or twice over the full life of the vehicle.
If I was trying to squeeze 150% out of a race engine then it is a different matter but you need to understand lawn mowers are really old technology and so understressed it is not funny.
Think about it.
My 1940 505 cc BSA side valve single is rated at 13 Hp
My 1972 499cc OHV single BSA is rated at 48Hp.
A brand new 498 cc OHV briggs is rated at 15 to 19 Hp
Nascars would be running 3 to 5 times the Hp/cc as a mower engine.
They are working hard and need every little bit they can get.
It depends upon the engine.
Side bangers all get strait SAE 30 mower oil
Honda walk behinds get 10W 30 mower oil for residential customers & 10W 40 for commercial customers.
late model kawakasi get 10W 40
All carby Kohlers apart from those under warranty get SAE 30
EFI Kohlers get 10W 40
Inteks get SAE 10w 30.
All of these a standard LAWN Mower oils
You see there is no such thing as the best oil for all.
I keep 5 gal of fully synthetic 5W 40 mower oil because 1 customer wants me to use it but he still gets his oil changes done at the same hours a if it was std oil and he pays $ 55 / litre.
He likes it because he is impatient and the mower fires up before the ignition key gets to the end of the rotation.
I go through 4 x 44's of 30 for every 44 of 10W 40 and 2 of those for each 10w 30.
Climate here is similar to Southern California and we mow all year round.
Synthetics are really a con but to comply with emissions at start up laws car companies specify them rather than modifing their engines.
That way you pay & they don't
OTOH the synthetic gear oils are a different kettle of fish, worth every extra cent but then Joe Average would only change the gearbox &/or diff oil once or twice over the full life of the vehicle.
If I was trying to squeeze 150% out of a race engine then it is a different matter but you need to understand lawn mowers are really old technology and so understressed it is not funny.
Think about it.
My 1940 505 cc BSA side valve single is rated at 13 Hp
My 1972 499cc OHV single BSA is rated at 48Hp.
A brand new 498 cc OHV briggs is rated at 15 to 19 Hp
Nascars would be running 3 to 5 times the Hp/cc as a mower engine.
They are working hard and need every little bit they can get.
#16
Ric
Ric
Re: The Reason I think Synthetic Oil is Best for 4-Cycle Mower Engines. "Who Agrees?"
Bert, your fighting a battle you can't win.:laughing: You'll never convince these guys that there's no advantage to running synthetic oils in a lawn mower. Fighting this battle is not unlike the fishing tackle industry and all the lures and they put on the market with all there claims. There lures are basically designed to catch fishermen, not fish and those guys, me included :laughing: just keep spending the money for all the gimmicks and looking for that miracle lure.
Synthetic oils in a lawn mower is nothing more than the industry gimmick. I've run mobile 5000 10w30 in all my Kohler and Kawasaki engines forever and never had any issues and here in Florida outside temps run between 85 and 105 degrees all summer and I'll run 4 to 5 hours sometime more every day. Change your oil every 50 hours with a filter change and you wont have any issues but as you said earlier if you want to run synthetic, spend the extra money and it makes you feel good run it.
Bert, your fighting a battle you can't win.:laughing: You'll never convince these guys that there's no advantage to running synthetic oils in a lawn mower. Fighting this battle is not unlike the fishing tackle industry and all the lures and they put on the market with all there claims. There lures are basically designed to catch fishermen, not fish and those guys, me included :laughing: just keep spending the money for all the gimmicks and looking for that miracle lure.
Synthetic oils in a lawn mower is nothing more than the industry gimmick. I've run mobile 5000 10w30 in all my Kohler and Kawasaki engines forever and never had any issues and here in Florida outside temps run between 85 and 105 degrees all summer and I'll run 4 to 5 hours sometime more every day. Change your oil every 50 hours with a filter change and you wont have any issues but as you said earlier if you want to run synthetic, spend the extra money and it makes you feel good run it.
#17
P
possum
P
possum
Re: The Reason I think Synthetic Oil is Best for 4-Cycle Mower Engines. "Who Agrees?"
Synthetic oils are not all that expensive anymore. NAPA has their synthetic on sale 2 to 4 times a year for 3 bucks a quart. Six years worth for 12 bucks on a pushmower. Nowhere in this small town I liver in can I get any oil for less. Most places it is 4 or 5 bucks a quart for conventional oil. I know people who have not left town for 5 years. Most of the time I can buy synthetic with a rebate for at or very near the same brand conventional. Sometimes for less. Mobil being one of them. But I do have to leave town. The synthetic gear oils are supposed to be a great deal better as was suggested but I can tell no visible difference after inspection of small gear boxes with 5000 hours on them. Synthetic oil runs more quiet in small engines but I doubt much more than that.
Synthetic oils are not all that expensive anymore. NAPA has their synthetic on sale 2 to 4 times a year for 3 bucks a quart. Six years worth for 12 bucks on a pushmower. Nowhere in this small town I liver in can I get any oil for less. Most places it is 4 or 5 bucks a quart for conventional oil. I know people who have not left town for 5 years. Most of the time I can buy synthetic with a rebate for at or very near the same brand conventional. Sometimes for less. Mobil being one of them. But I do have to leave town. The synthetic gear oils are supposed to be a great deal better as was suggested but I can tell no visible difference after inspection of small gear boxes with 5000 hours on them. Synthetic oil runs more quiet in small engines but I doubt much more than that.
#18
S
sidemouse
S
sidemouse
Re: The Reason I think Synthetic Oil is Best for 4-Cycle Mower Engines. "Who Agrees?"
And what goes in a Generac or do I just use the Kohler oil, wait how's that work again?
All that does is confuse the consumer.
Keep it simple...
One oil, all 4-cycle gasoline engines.
I have close to 30 engines on my property, all different makes and models.
Someone expects me to carry fourteen different kinds of oil, preferably several quarts of each?
Ok that's good, here's my Toro 30197 cv-15t, what's it take, 10w-30?
Oh you wrote it down, did you, where's that piece of paper again...
Your quote: All carby Kohlers apart from those under warranty get SAE 30
That's odd because the CV-15t Kohler Owner's manual recommends 10w-30 as per the manufacturer.
Who are we kidding?
That's why I run 5w-20 full synthetic in all 4-cycle gasoline engines.
Guess what oil goes in my Honda engines?
Yes, I have at least four or five of these...
If you guessed 5w-20 full synthetic you would be right!
Better yet there is no other 4-cycle engine oil on my whole property, so if you grabbed a quart you got it.
How simple was that?
No looking up charts, no hunting down owner's manuals, no pecking through the inventory to find that one special quart bottle.
Also eliminates the off chance of running air compressor oil in my gasoline engine, or chainsaw lube.
Yeah I forgot, I have to carry chainsaw lube, air compressor oil, oh and 2-cycle mix as well.
One oil, all 4-cycle gasoline engines.
And if 5w-20 full synth doesn't float your boat pick one that does, then stick to it and if things don't work out at least you'll know where to start.
One oil, all 4-cycle gasoline engines.
Simplifies life a whole lot.
It depends upon the engine.
Side bangers all get strait SAE 30 mower oil
Honda walk behinds get 10W 30 mower oil for residential customers & 10W 40 for commercial customers.
late model kawakasi get 10W 40
All carby Kohlers apart from those under warranty get SAE 30
EFI Kohlers get 10W 40
Inteks get SAE 10w 30.
All of these a standard LAWN Mower oils
And what goes in a Generac or do I just use the Kohler oil, wait how's that work again?
All that does is confuse the consumer.
Keep it simple...
One oil, all 4-cycle gasoline engines.
I have close to 30 engines on my property, all different makes and models.
Someone expects me to carry fourteen different kinds of oil, preferably several quarts of each?
Ok that's good, here's my Toro 30197 cv-15t, what's it take, 10w-30?
Oh you wrote it down, did you, where's that piece of paper again...
Your quote: All carby Kohlers apart from those under warranty get SAE 30
That's odd because the CV-15t Kohler Owner's manual recommends 10w-30 as per the manufacturer.
Who are we kidding?
That's why I run 5w-20 full synthetic in all 4-cycle gasoline engines.
Guess what oil goes in my Honda engines?
Yes, I have at least four or five of these...
If you guessed 5w-20 full synthetic you would be right!
Better yet there is no other 4-cycle engine oil on my whole property, so if you grabbed a quart you got it.
How simple was that?
No looking up charts, no hunting down owner's manuals, no pecking through the inventory to find that one special quart bottle.
Also eliminates the off chance of running air compressor oil in my gasoline engine, or chainsaw lube.
Yeah I forgot, I have to carry chainsaw lube, air compressor oil, oh and 2-cycle mix as well.
One oil, all 4-cycle gasoline engines.
And if 5w-20 full synth doesn't float your boat pick one that does, then stick to it and if things don't work out at least you'll know where to start.
One oil, all 4-cycle gasoline engines.
Simplifies life a whole lot.
#19
R
RoofTopPigeon
R
RoofTopPigeon
Re: The Reason I think Synthetic Oil is Best for 4-Cycle Mower Engines. "Who Agrees?"
Thanks; sidemouse;
I will run my Personal Preferance of Full-Synthetic
Valvoline 5W-30 with Max Life Technology. In my 4-Cycle Engines.
That's why I run 5w-20 full synthetic in all 4-cycle gasoline engines.
Thanks; sidemouse;
I will run my Personal Preferance of Full-Synthetic
Valvoline 5W-30 with Max Life Technology. In my 4-Cycle Engines.
#20
D
DK35vince
D
DK35vince
Re: The Reason I think Synthetic Oil is Best for 4-Cycle Mower Engines. "Who Agrees?"
I use one oil, Rotella T-6 5w-40 synthetic in my tractor, garden tractor, zero turn, ATV, generators, push mowers, water pumps, pressure washer, Etc.
I use one oil, Rotella T-6 5w-40 synthetic in my tractor, garden tractor, zero turn, ATV, generators, push mowers, water pumps, pressure washer, Etc.
#21
G
greenguy
G
greenguy
Re: The Reason I think Synthetic Oil is Best for 4-Cycle Mower Engines. "Who Agrees?"
I know a guy that bought a Craftsman push mower in 1989, has NEVER changed the oil, just keeps adding to this day. Personally I think he should be horse whipped!!!!!
I know a guy that bought a Craftsman push mower in 1989, has NEVER changed the oil, just keeps adding to this day. Personally I think he should be horse whipped!!!!!
#22
D
deck~dragger
D
deck~dragger
Re: The Reason I think Synthetic Oil is Best for 4-Cycle Mower Engines. "Who Agrees?"
I can not believe the amount of time that is put into some of these posts:confused2: Oil has improved exponentially over the years.
I did learn something from Bert though-
Before the engine is laid up over winter.
Synthetic or non synthetic, sitting in the sump for 4 months going nowhere and gravity will do its dirty work and deposit all of the heavy nasties that were suspended in the oil into the lower bush and all of the lighter acidic nasties will float to the top doing their best to turn your engine into scrap metal.
This efect is worse in synthetics than std oils because they are freer draining
I can not believe the amount of time that is put into some of these posts:confused2: Oil has improved exponentially over the years.
I did learn something from Bert though-
Before the engine is laid up over winter.
Synthetic or non synthetic, sitting in the sump for 4 months going nowhere and gravity will do its dirty work and deposit all of the heavy nasties that were suspended in the oil into the lower bush and all of the lighter acidic nasties will float to the top doing their best to turn your engine into scrap metal.
This efect is worse in synthetics than std oils because they are freer draining
#23
B
bertsmobile1
B
bertsmobile1
Re: The Reason I think Synthetic Oil is Best for 4-Cycle Mower Engines. "Who Agrees?"
Improved is loaded word as is best.
What has happened over the years is we have learned how to take crude that is totally unsuitable for use as lubricating oil and turn it into 1st class lubricating oils.
We have learned how to fortify light oil so it behaves like heavy oil at operating temperatures thus extending the oil supply and reducing the costs.
However 5w30 will never be as good as strait 30 in some applications for no other reason that what was done to make it 30 will get undone over time
Where as 30 will remain 30 for so long as it does not get cooked.
Racing has led to developing thinner oils that can take a lot more punishment and tougher thinner oils has allowed for much tighter clearences.
Engine technology has gone so far than now days the viscious drag of the oil becomes significant.
This is important in racing where every Hp is so precious a lot of top class drives shove a supository up their clacker before a race to evacuate their bowel and reduce weight by a pound or two.
Motorcyclists from the kick start days are very aware of this as it is significantly harder to kick your bike running heavy summer oils than it is to kick it with light winter oils.
The 13 Hp M20 has the same top speed running any oil but the 65 Hp Yammie lost 25 kph when running on heavy summer oil.
The exact same engine used for 3 different applications will require 3 different oils.
Snow blowers need to be able to start at very low temperatures so they need a light oil to be able to start, mowers get started on hot days & used in hot situations thus a heavier oil is required while generators need to span an even wider range of temperatures and be stable for very long running periods and to transfer heat a lot better than a snow blower.
However none of this is relevant to lawn mowers and doubly so to Briggs & Kohler engines which are so under stressed that the oil drag is inconsequential .
The prime factor in the design of a mower engine is CHEAP and cheap = loose.
You can get 40Hp out of a 500cc intek but the only original parts used will be the cases & crank and the engine will end up costing a couple of grand.
For a couple of grand most now days expect a complete mower along with a bikini clad cutie pie to bring you cold drinks.
Thus mower engines are crude rude & unsofisticated, for now with wide open running clearences that are too big for thin oils to maintain metal separation.
However the one thing that has never changed is an engine produces by-products that contaminate the oil which need to be removed and the most effective way of removing them is to change the oil.
Synthetics are a lot more stable and the addative packages remain in a useful condition for a longer period, but the contaminants still concentrate in the oil thus the oil still needs to be changed.
The frequency of the oil changes is determined by the design parrameters of the engine, not the oil.
A good example of this is a friend who had an A65 BSA that had a worn main bush and was bleeding off oil pressure.
It had done near 20,000 miles when he got it cheap so was 2/3 through the design life of the bottom end.
Rhett ran this bike on deisel oil which he got cheap from work.
He changed the oil every time he used the bike.
He sold that bike 35 years latter with over 80,000 miles on the clock, still on the same bottom end that he bought it with.
The new owner had thrown a rod within a year.
SO the BEST oil for any engine, is the oil that has just been changed.
Prior to becoming a small engine mechanic , I ran hire car business & courier company.
Everything ran on recycled 20w 50 which meant I could buy it in 44's for 1/6 the price of retail packs of virgin oil.
The Mitsubishi vans were fine, the Yamahas used a bit more than they should and the Rollers gobbled oil at an alarming rate.
However the hire cars got oil changes ever 3 months which was 1/2 the time internvals & about 1/20 the mileage intervals recommended.
The vans got monthly oil changes and the motorcycles were weekly or fortnightly depending upon the rider.
We had no oil related problems with any vehicle for near 30 years.
Improved is loaded word as is best.
What has happened over the years is we have learned how to take crude that is totally unsuitable for use as lubricating oil and turn it into 1st class lubricating oils.
We have learned how to fortify light oil so it behaves like heavy oil at operating temperatures thus extending the oil supply and reducing the costs.
However 5w30 will never be as good as strait 30 in some applications for no other reason that what was done to make it 30 will get undone over time
Where as 30 will remain 30 for so long as it does not get cooked.
Racing has led to developing thinner oils that can take a lot more punishment and tougher thinner oils has allowed for much tighter clearences.
Engine technology has gone so far than now days the viscious drag of the oil becomes significant.
This is important in racing where every Hp is so precious a lot of top class drives shove a supository up their clacker before a race to evacuate their bowel and reduce weight by a pound or two.
Motorcyclists from the kick start days are very aware of this as it is significantly harder to kick your bike running heavy summer oils than it is to kick it with light winter oils.
The 13 Hp M20 has the same top speed running any oil but the 65 Hp Yammie lost 25 kph when running on heavy summer oil.
The exact same engine used for 3 different applications will require 3 different oils.
Snow blowers need to be able to start at very low temperatures so they need a light oil to be able to start, mowers get started on hot days & used in hot situations thus a heavier oil is required while generators need to span an even wider range of temperatures and be stable for very long running periods and to transfer heat a lot better than a snow blower.
However none of this is relevant to lawn mowers and doubly so to Briggs & Kohler engines which are so under stressed that the oil drag is inconsequential .
The prime factor in the design of a mower engine is CHEAP and cheap = loose.
You can get 40Hp out of a 500cc intek but the only original parts used will be the cases & crank and the engine will end up costing a couple of grand.
For a couple of grand most now days expect a complete mower along with a bikini clad cutie pie to bring you cold drinks.
Thus mower engines are crude rude & unsofisticated, for now with wide open running clearences that are too big for thin oils to maintain metal separation.
However the one thing that has never changed is an engine produces by-products that contaminate the oil which need to be removed and the most effective way of removing them is to change the oil.
Synthetics are a lot more stable and the addative packages remain in a useful condition for a longer period, but the contaminants still concentrate in the oil thus the oil still needs to be changed.
The frequency of the oil changes is determined by the design parrameters of the engine, not the oil.
A good example of this is a friend who had an A65 BSA that had a worn main bush and was bleeding off oil pressure.
It had done near 20,000 miles when he got it cheap so was 2/3 through the design life of the bottom end.
Rhett ran this bike on deisel oil which he got cheap from work.
He changed the oil every time he used the bike.
He sold that bike 35 years latter with over 80,000 miles on the clock, still on the same bottom end that he bought it with.
The new owner had thrown a rod within a year.
SO the BEST oil for any engine, is the oil that has just been changed.
Prior to becoming a small engine mechanic , I ran hire car business & courier company.
Everything ran on recycled 20w 50 which meant I could buy it in 44's for 1/6 the price of retail packs of virgin oil.
The Mitsubishi vans were fine, the Yamahas used a bit more than they should and the Rollers gobbled oil at an alarming rate.
However the hire cars got oil changes ever 3 months which was 1/2 the time internvals & about 1/20 the mileage intervals recommended.
The vans got monthly oil changes and the motorcycles were weekly or fortnightly depending upon the rider.
We had no oil related problems with any vehicle for near 30 years.
#24
R
RoofTopPigeon
R
RoofTopPigeon
Re: The Reason I think Synthetic Oil is Best for 4-Cycle Mower Engines. "Who Agrees?"
I'm going to Agree Here bertsmobile1!
SO the BEST oil for any engine, is the oil that has just been changed.
I'm going to Agree Here bertsmobile1!
#25
stevestd
stevestd
Re: The Reason I think Synthetic Oil is Best for 4-Cycle Mower Engines. "Who Agrees?"
bertsmobile1 wrote: “However the one thing that has never changed is an engine produces by-products that contaminate the oil which need to be removed and the most effective way of removing them is to change the oil”.
Just finished changing the oil on my mowers, and my mechanic son used engine flush which seems to work as the oil is the same colour as what went in after some minimal use. This I suppose is beneficial, especially with small mowers with no oil filter? I use mineral based Honda oil in engines (10w-30), and full synthetic oil in the hydrostatic drives (15w-50) as per owner manuals.
bertsmobile1 wrote: “However the one thing that has never changed is an engine produces by-products that contaminate the oil which need to be removed and the most effective way of removing them is to change the oil”.
Just finished changing the oil on my mowers, and my mechanic son used engine flush which seems to work as the oil is the same colour as what went in after some minimal use. This I suppose is beneficial, especially with small mowers with no oil filter? I use mineral based Honda oil in engines (10w-30), and full synthetic oil in the hydrostatic drives (15w-50) as per owner manuals.