From Kubota To Scag......First Impressions

Lawnman48

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You can or you can't change oil and air filters to early?
 

cpurvis

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Pleated paper filters get progressively better as they get dirty. The biggest particles not captured by the filter will be when it is brand new.
 

BTBO

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Scag operators manual for Liberty Z, engine oil/filter change intervals;
8 hours, change engine oil and filter.
Change engine oil after 50 hours or annually.
Change engine oil and filter after 100 hours.
Kawasaki FR651V, FR691V, FR730V Owners Manual/General-purpose Engine Owner's Manual:
The important words are 'General-purpose'!! This refers the operator to the specific machine operators/owners manual recommendations.
No break-in info.
100 hour engine oil change interval.
200 hour engine oil filter change interval.
Kawasaki sells engines, Scag sells some of the best Zero Turn Mowers available, think about this!
Take it from an old mech, you can change engine oil too often and you can change air filters too often! Air filters are a condition change item with the owners manual recommending the maximum time before change.
New engines are delivered to equipment manufacturers dry with no oil. Who knows what they put in the engines, just a hint, some mowers use 20W50 dino oil in the hydraulic systems so this oil is very available on the assembly lines, just a hint!!!
Mad Mackie----Not to doubt your claim of it being possible to change engine oil too often------Would you please elaborate and explain why that is? Also, when time, I plan on draining the hydro oil at the specified time and filling with Amsoil synthetic 20W50. It claims to be specically formulated for hydrostatic systems on my Scag Liberty Z 48".
 

Mad Mackie

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I'm not a lube oil expert by any stretch of the imagination, but I do have many years of dealing with engines of many types.
Multi-viscosity engine oil has additives to make it multi-viscosity. Some of these additives have a very strong detergent ability to them. As engine run time increases, the detergent ability of the oil decreases as the oil breaks down. During this time, the oil filter collects the small particles that the oil has picked up and the cleaning quality of the oil "settles down" so to speak. This allows the oil to continue to lubricate but with less cleaning quality which is OK and when it is up to operating temperature, the moisture and unburned fuel that has collected in the engine and oil will vaporize.
When the engine oil is changed too often, the detergent cleaning quality of the oil is refreshed each time and the "settle down" time period of the oil isn't long enough. This prolongs the engine break in period and sometimes will not allow the engine to reach full break in. Piston rings and cylinder walls are the areas where break in is most affected.
Many small engines may take up to 50 hours of operation to settle in and reach a good break in condition. Some operators may only put 50 hours on a mower in half hour intervals in a year and some may put on many more hours in a year. Folks that run their machines for short times may not run long enough for the engine oil and drive systems oil to warm up and properly operate.
A few more thoughts:
Full synthetic engine oils have a stronger detergent quality to them than multi-viscosity fossil oils.
While any machine, engine or drive train is still under warranty from the manufacturer, it is highly recommended to use OEM filters and suggested lube oils and greases. I have seen where an engine failed while using OEM filters and the engine manufacturer replaced the engine even after the warranty had expired. I have seen the opposite where engine replacement on warranty was denied due to non OEM filters and non recommended oils having been used.
You decide!
 
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bertsmobile1

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You have been watching too many Castrol TV adds.
Detergent oils clean nothing never have and never will
A detergent molecule will attach itself to anything other than oil, at one end only.
So what ends up happening is particales of crud in the oil end up with hundreds of detergent molecules totally engulfing them
When this big hairy blob gets to the filter, it gets stuck there, thus both the crud & the detergent molecules remain in the filter.
This can be as fine as a single pair of carbon atoms with 4 detergent molecules stuck like glue to them , or so they say ,
The bigger the detergent molecule the better the filter can remove them.

Your dishwashing detergent works the exact same way.
It has a pH raining salt ( same as cloths washing detergents ) that raise the pH which is what does the cleaning.
then the detergent molecules engulf the crud that has been dissolved off your dirty dinner plate so it stays in the dishwater and does not redeposit itself on your dishes.
There are some surficants in there as well which is why it bubbles & froths

Put a high detergent oil in a dirty engine and it will be every bit as dirty when you take it out.
Because we actually have an advertising standards department those type of stretching the truth to cover a lie adds don't run for long down here .

Monogrades that get used in older engines with DRY SUMPS do not have detergents because they rely on the little bits of crud bumping into each other and making big bits of crud so they will settle to the bottom of the oil tank and form a sludge.
during operation you get a fair amount of mixing between the circulating oil and the lighter portion of the sludge so it is recommended that OLD DRY SUMP engines have the oil tank removed & cleaned prior to using a detergent oil as the detergent will grab the big bits of loose crud and make them really big bits of crud.
The detergent molecules are lighter than the oil molecules so the big bits of crud which would usually sit below the outlet of the oil tank end up having an overall lower density caused by all of the detergent molecules wrapped around them.
Thus they end up floating high enough to be sucked back into the engine where in the case of BSA motorcycles they get pulled out by the full flow centrifugal oil filter inside the crankshaft , generally called a sludge trap.
When you run a very high detergent oil the floated off crud very quickly can fill up the sludge trap & block off the oil flow through the crank.
I think HD's have a similar trap in their cranks.
A detergent is basically a dispersant which is why you spray them on oil slicks to break them up but in that case the dispersant molecule is the same density as sea water so it breaks up the oil slick while preventing all of it dropping directly to the bottom of the watercoarse and forming a blanket on the bottom thus killing off everything there.
 

Mad Mackie

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How did I know that bertsmobile1 would post a scientific response!
Back in the 60s Exon came out with Uniflo 10W30 detergent engine oil. According to Exon, this was the final answer to the best engine oil ever. A lot of automobile service businesses started using this oil in customers cars. Back then not many engines had full flow engine oil filters as most had the 10% filters. Many engines of that vintage had hydraulic valve lifters and the first indication of the use of Uniflo 10W30 oil was clacking valve lifters. As time went on and some mechs wanted to find out what was causing the lifters to collapse, they found that crud that had been loosened up by the detergent engine oil had plugged the small holes in the lifters where oil under pressure supplied the lifters to keep them pumped up.
Castrol multi-viscosity engine oil was another source of this problem. Having been a member of the Service Managers Association in the 70s and 80s, we would get together and swap stories. There were folks from power equipment, marine and automotive businesses attending these meetings.
I have some knowledge of air cooled engines having been an aircraft mech for many years and dealt with small opposed four cylinder 65 HP Continentals to 28 cylinder, four rows of 7 cylinders on Pratt & Whitney R4360 3,500 HP radial engines, both dry sump and wet sump and aerobatic sumps. I also dealt with turbine engines when the change over to synthetic engine oils was going on. Also hydraulic systems were changed over to fire retardant synthetic fluids. We had to deal with all of this as mechs and it wasn't pleasant.
I'm done, I gotta get to work on some power equipment and make some billable hours!!
I still love you my fellow wrench brother and always look forward to your posts!
 

cpurvis

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Long time ago, I worked for a guy who had air tankers. Got to work on Wright R3350's, and P&W R2000's and R2800's. Very minor stuff, though, like plug changes, prop changes. R2800's were the most common as he had a lot of Douglas A26's. If they were running right, you could read the engine data plates from the pilot's seat if the cowls were removed.

IIRC, they all ran straight 50W Ashless Dispersant oil which was always black as coal, even though the engines consumed a lot of it.
 

bertsmobile1

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How did I know that bertsmobile1 would post a scientific response!
Back in the 60s Exon came out with Uniflo 10W30 detergent engine oil. According to Exon, this was the final answer to the best engine oil ever. A lot of automobile service businesses started using this oil in customers cars. Back then not many engines had full flow engine oil filters as most had the 10% filters. Many engines of that vintage had hydraulic valve lifters and the first indication of the use of Uniflo 10W30 oil was clacking valve lifters. As time went on and some mechs wanted to find out what was causing the lifters to collapse, they found that crud that had been loosened up by the detergent engine oil had plugged the small holes in the lifters where oil under pressure supplied the lifters to keep them pumped up.
Castrol multi-viscosity engine oil was another source of this problem. Having been a member of the Service Managers Association in the 70s and 80s, we would get together and swap stories. There were folks from power equipment, marine and automotive businesses attending these meetings.
I have some knowledge of air cooled engines having been an aircraft mech for many years and dealt with small opposed four cylinder 65 HP Continentals to 28 cylinder, four rows of 7 cylinders on Pratt & Whitney R4360 3,500 HP radial engines, both dry sump and wet sump and aerobatic sumps. I also dealt with turbine engines when the change over to synthetic engine oils was going on. Also hydraulic systems were changed over to fire retardant synthetic fluids. We had to deal with all of this as mechs and it wasn't pleasant.
I'm done, I gotta get to work on some power equipment and make some billable hours!!
I still love you my fellow wrench brother and always look forward to your posts!

Yes it was a problem with engines that relied on debris settleing out and forming a sludge suddenly having all of the contiminants staying in suspension.
IT is staggering just how much of the solids just stick together & drop to the bottom of the oil tank or sump.
However the story is still the same the detergent is not cleaning the engine as the TV adds suggested, it is just stopping the crud falling out of the oil and sitting in the bottom of whatever was used to collect the crud.
Hydraulic lifters would be a horror story because the entry hole is tiny.
The set up is exactly the same with BSA engines because the internal crankshaft filter was supposed to be cleaned out every 30,000 miles with the sludging mono grade oils .
This final filter was only ever designed to catch the stuff that did not form a sludge in the bottom of the oil tank , probably 5% to 20% of the total particulate contamination.
Suddenly it trapped 100% of all of the particulates and would block solid in as little as 10,000 miles thus the left side big end got little to no oil and got really annoyed so jumped out of the engine.
I have pulled apart engines where the sludge is packed in so hard it had to be drilled out with a very sharp wood drill because standard metal drills went blunt in a few minutes.
The manual tells you to hook the end of the basket with some wire, pull it out and reverse flush it.

So the problem you had then was idiots running their cars & trucks on a type of oil it was not designed to run on.
Back before spin on oil filters we used to drop the sump every couple of oil changes and scrape the mud out of the bottom as the sumps were deeper and used as sludging tanks,
Same story for tappet adjustments, part & parcel of this was manually washing the accumulated sludge from the inside on the rocker covers.
These build ups of "mud" were intentional and part of the lubrication system.
Once detergent / dispersant oil came into popular useage, this crud was still made by the engine, the only difference was it was supposed to be caught by the oil filter as finner particals not big blobs of sludge.
Ashless oils do not form anywhere as much sludge because they do not "burn" ( oxadize ) to the same extent as regular oils and can take a lot higher temperatures.
Prior to synthetic oils becoming popular most of the "ashless" oils came from Australia as our crudes contain no sulphur , no phosphorus and have the lowest ash content of any crude on the planet.
Thus we would export crude to the USA for refining into lubricating oil while importing crude to be processed into petrol because our crude made very low energy petrol because it has fewer volatiles ( which is why it has such a low ash content ).

The widespread adoption of synthetic oil for lubrication is the driving force behind the closure of all but 2 of the Australian Oil refineries as what our oil was desperately needed for ( mostly avaition oils ) no longer existed so we could not get premium prices for it.

As an aside that is the same reason why we export so much coal as just like the oil our coal deposits have the lowest Sulphur content ( no acid rain from burning it ) low Phosphouous and very low ash while having the highest coke crush strength ( good in blast furnaces & cupolas ) .

However I have ranted on for way too long.
The only point I really wanted to make is it is not the detergency that was causing the problems with bed in and "DETERGENTS DO NOT CLEAN" they are nothing more than an aid in transporting muck away which of course can & will end up depositing in all sorts of places where you don't want it to if the engine was designed to run on a standard oil.
I am no oil expert but I had some riding companions who were, but part & parcel of one of my degree was a short course on oils explaining what they were, what they do & how they do it. What was added, why it was added & how it worked.
Unfortunately this is missing from most certificate & diploma automotive engineering courses which is jhow advertising agencies get away with twisting facts into lies and confusing the public at large.
 

Mad Mackie

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Long time ago, I worked for a guy who had air tankers. Got to work on Wright R3350's, and P&W R2000's and R2800's. Very minor stuff, though, like plug changes, prop changes. R2800's were the most common as he had a lot of Douglas A26's. If they were running right, you could read the engine data plates from the pilot's seat if the cowls were removed.

IIRC, they all ran straight 50W Ashless Dispersant oil which was always black as coal, even though the engines consumed a lot of it.

From 81-94 I was an active duty member of the CTARNG and was a part timer before 81. We had Caribou aircraft with twin P&W R2000 7M2 engines, C45s with P&W R985s, Beavers with P&W R985 and Otters with P&W P&W R1340. CH37 helicopters with P&W R2800s with no reduction gear as they drove the transmissions for the rotor system. These R2800s were mounted on their backs with the output shafts vertical. Over the years many ex Army aircraft came to us for maintenance and reissue to other units.
The Designated Maintenance Examiner that I dealt with lived nearby and he was a 727 and a C-97 flight engineer. The outfit that flew freight in C-97s would periodically come to Bradley International Airport (BDL) in Windsor Locks, CT and I was called out by him to help do urgent maintenance on the R4360s on the C-97s. Doing a cylinder or two changes on R4360s outdoors was challenging to say the least with a serious 28 stack exhaust system many parts of which had to be removed before a cylinder removal could happen, but not until the cowlings were removed from the engine.
We used nondispersant mineral oil in overhauled round engines for the first 50 or so hours and then switched to LAD ll or LAD lll, ashless dispersant depending on the ambient temps. LAD LL is 50 weight as you know and LAD lll is 60 weight. Using non-disp oil initially made a lot of difference in oil consumption as it allowed the engines to "coke up" and seat the piston rings before switching to ashless disp oil. Very few of our round engines actually made it to TBO which was 1,500 hours. Military round engine cylinders were all chromed in the bore.
 

cpurvis

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Here's a picture of the B-17G, tanker 102. I never worked on it; only saw it once before it was sold.

IIRC, the fleet was:
1-B17G, which is now in the Palm Springs museum (see link; tanker 102 N3509G, named Miss Angela) http://www.air-and-space.com/Boeing B-17 Tankers.htm
2-DC-7B, one of which crashed near Pecos, TX.
6-Navy "DC-4's" (R5-D's?) which came out of the boneyard in AZ. Helped put tanks on these.
5-Douglas A-26 (machine guns nose)
1-Douglas B-26 (bombardier nose)

Previously had a Consolidated Privateer which was lost in a fire at Wenachee, WA airport.

He also had some Lockheed P2V's (or was it PV-2), but these were sprayers. Had internal tanks and wing booms. Used for spraying Malathion on mosquitoes.

A friend of his found a stock military A-26 with bomb racks still installed in an auto salvage yard in Marion, KS. The neighbor and his hired hand borrowed two fresh R2800's, went through the plane over one winter, and Bill (the guy I worked for) flew it home.

That was one of the most interesting jobs I had.

Sorry for the thread drift.
 
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