Oils

[Skippydiesel]

I wash and re-oil my pre-cleaner after every mow , the book says 25 hours ,do not think so
Oz

Filter efficiency increases (gets better) to the point where they start to create excessive blockage/restriction. I guess its a judgement thing but I only clean my filters once per year avoid cutting low (min 100mm) so less dust - never had an air filter come close to blocking.

My immediate after use care is - all my dust makers (mowers/brush cutters) are meticulously blown (high pressure air) clean after each use. I am complete against washing (may be once every few years).

 

[RevB]

My mistake - as far as I know all oils sold in Australia are number (30) followed by W - we don't have much call for winter fuels/oils.

A confession....you aren't wrong. I am. That's what age gets ya. Here is a link to the real data. I was thinking of the ratings from the 1950s.....

SAE J300 - Wikipedia

en.m.wikipedia.org

 

[shurguywutt]

I like a 5w-40 synthetic or synthetic blend. I was using a 30w but found it was harder to start especially when I got cooler weather. I have also heard rumors of engine problems being caused by trying to start the engine in cooler weather (60* F / 15* C) and below with 30w.

 

[Skippydiesel]

I like a 5w-40 synthetic or synthetic blend. I was using a 30w but found it was harder to start especially when I got cooler weather. I have also heard rumors of engine problems being caused by trying to start the engine in cooler weather (60* F / 15* C) and below with 30w.

Not usually a problem in Australia, unless you live in the high country or Tasmania

 

[Old Gweilo]

Yes! I realise this topic may have been discussed to death already but recommendations seem to change over time so I thought why not give it another go.

I live in Australia - climate range can go from 0C (rarely) - 47C (also rare). Mowing range mostly 21- 40C (grass growing).

In my small engines - push mowers/pumps/generator/ compressor, older ride on (B & S 17 hp) I use a straight, single grade, mineral oil W30 - never had a problem.

Put a new Kawasaki 22hp in my commercial zero turn - Mower shop recommended I use a semi synthetic 10W-40 with Zinc. Kawasaki manual says I can use the 10W- 30 or 40 OR the straight W30 BUT advises that fuel consumption will go up with the multigrade oils.

I am happy to put a semi synthetic multigrade in my "Kwaka" IF there a real benefit, otherwise will use the W30.

What is your advice?

Don’t under rate the zinc recommendation. My HD manual recommends their Motorcycle oil or if that isn’t available a suitable weight oil rated for diesel engines. What do MC oils and diesel oils have in common? Both are much higher in zinc than automotive oils. This may explain the mysterious inclusion of 20 / 50 oils in later iterations of the Kwai manuals. These 20 / 50 oils are almostly exclusively blended for MC’s so are high in zinc.

Hope this helps.

 

[Old Gweilo]

Yes! I realise this topic may have been discussed to death already but recommendations seem to change over time so I thought why not give it another go.

I live in Australia - climate range can go from 0C (rarely) - 47C (also rare). Mowing range mostly 21- 40C (grass growing).

In my small engines - push mowers/pumps/generator/ compressor, older ride on (B & S 17 hp) I use a straight, single grade, mineral oil W30 - never had a problem.

Put a new Kawasaki 22hp in my commercial zero turn - Mower shop recommended I use a semi synthetic 10W-40 with Zinc. Kawasaki manual says I can use the 10W- 30 or 40 OR the straight W30 BUT advises that fuel consumption will go up with the multigrade oils.

I am happy to put a semi synthetic multigrade in my "Kwaka" IF there a real benefit, otherwise will use the W30.

What is your advice?

On the topic of synthetics, yes they are better. That said if you can only justify paying synthetics prices by extending change intervals then stick with regular oil and change it on schedule. So, buy a synthetic oil by all means, just don’t buy the “extended interval yarn” that comes with it. Synthetics carry benefits which go beyond durability and these are the reasons I use it.

Synthetics and regular oils differ in base oil characteristics but both have similar “package” components and it it these package components which deplete and shear. Don’t extend !

 

[Ozcub]

On the topic of synthetics, yes they are better. That said if you can only justify paying synthetics prices by extending change intervals then stick with regular oil and change it on schedule. So, buy a synthetic oil by all means, just don’t buy the “extended interval yarn” that comes with it. Synthetics carry benefits which go beyond durability and these are the reasons I use it.

Synthetics and regular oils differ in base oil characteristics but both have similar “package” components and it it these package components which deplete and shear. Don’t extend !

I hear what you are saying but the Hydro-gear manual states that by using a full synthetic you double the change time I only use a regular oil in the engine
As for the air filters , I reverse vacuum the air filter gently and wash and re-oil the pre-cleaner after every mow and as Skippydiesel says give it a good blow and wipe down after every mow
Gweilo is a "name" Chinese use
Oz

 

[Skippydiesel]

Don’t under rate the zinc recommendation. My HD manual recommends their Motorcycle oil or if that isn’t available a suitable weight oil rated for diesel engines. What do MC oils and diesel oils have in common? Both are much higher in zinc than automotive oils. This may explain the mysterious inclusion of 20 / 50 oils in later iterations of the Kwai manuals. These 20 / 50 oils are almostly exclusively blended for MC’s so are high in zinc.

Hope this helps.

Tad off topic, sorry -

Motorcycles (or any engine) with integrated gear box or using the same oil in gearbox as crankcase should, in general , not use friction (zinc?) modified oils.

I am not sure about your MC/diesel oils commonality being zinc - I will investigate.

Zinc seems to be a relativly recent innovation - I suspect the marketing, rather than technical, department. Not saying zinc may not do good things for the engine (specially the aircooled variety).

If in doubt, contact motorcycle/oil manufacture technical department for advice/recommendations.

 

[Rifraph48]

Yes! I realise this topic may have been discussed to death already but recommendations seem to change over time so I thought why not give it another go.

I live in Australia - climate range can go from 0C (rarely) - 47C (also rare). Mowing range mostly 21- 40C (grass growing).

In my small engines - push mowers/pumps/generator/ compressor, older ride on (B & S 17 hp) I use a straight, single grade, mineral oil W30 - never had a problem.

Put a new Kawasaki 22hp in my commercial zero turn - Mower shop recommended I use a semi synthetic 10W-40 with Zinc. Kawasaki manual says I can use the 10W- 30 or 40 OR the straight W30 BUT advises that fuel consumption will go up with the multigrade oils.

I am happy to put a semi synthetic multigrade in my "Kwaka" IF there a real benefit, otherwise will use the W30.

What is your advice?

My opinion: I live in central Texas where the climate sounds similar. I use 10W-30 Racing Oil (higher zinc) in my non-filter (splash lube) engines and 15W-40 Racing Oil in my filtered (oil pump) engines. These give higher HTHS test results and there is no catalytic convertor to protect. The 10W/15W thinner oil gives immediate lubrication at startup especially on the cooler mornings. You want a high quality oil that uses high quality base oils.

Beware of the "I have never had any problems" thinking as that is based on ignorance not data. Often, you are unaware of damage until it causes the engine to fail. I think it is best to think through the risks and determine how to minimize them. I think a key test result is HTHS. Thinner oils have lower readings and use additives that wear out with time. There are no doubt 100,000 + other opinions...

 

[BudTugley]

Put a new Kawasaki 22hp in my commercial zero turn - Mower shop recommended I use a semi synthetic 10W-40 with Zinc. Kawasaki manual says I can use the 10W- 30 or 40 OR the straight W30 BUT advises that fuel consumption will go up with the multigrade oils.

I am happy to put a semi synthetic multigrade in my "Kwaka" IF there a real benefit, otherwise will use the W30.

View attachment 70430

On the oil recommendations chart it says use API: SF, SG, SH, SJ or SL. That is the same thing as saying use high Zinc oil, because when you get to SM is when zinc was reduced by 47% to extend catalytic converter life in automobiles, and when air cooled engine oil was born, which is basically the same thing automotive oil use to be before they reduced the zinc.

Zinc is short for a compound ZDDP (Zinc dialkyldithiophosphate). It makes the oil more thermally conductive which allows it to better cool the engine. It also creates a slick film over surfaces to reduce wear.

Running lower zinc automotive oil is not likely to result in any problem in the short run, but over time more heat and more wear will reduce the life of the engine.

Multi-weight oil such as 10w40 is not as thick when it is cold, which allows faster circulation on startup. It is generally recommended to run multi-weight oil in engines that have overhead components to be lubricated because the lubricant can reach those components faster on startup, which reduces startup wear. Most modern air-cooled engines are now overhead valve.

About impact on fuel consumption. I think your manual was speaking about oil consumption.

The high zinc 10w40 semi-synthetic that your local shop is recommending sounds like a winner. It sounds like it may be K-Tech 10w40. All the K-Tech motor oils from 10w30 to 15w50 are rated SL meaning they are high zinc(ZDDP).