Kawasaki 15 w 50

I run Royal Purple 20W-50 in my '95 Harley and it is a vast power improvement over the SAE 50 Harley oil they were recommending. Straight SAE 50 is way outdated in my opinion.

Air cooled engines are critical about the correct viscosity for the ambient temperature conditions. The most wear on any air-cooled engine is in the first couple of minutes during initial warmup. That is where multi-weight oils work the best.

For rider equipment I use STP 10W-30 most of the time and make sure the level is maintained especially in hotter climates and prolonged run times.

Anyone who thinks an air-cooled engine does not burn a little bit of oil is sadly mistaken or too cheap to keep extra oil at the ready when needed.

I am not a fan of the older straight weight oils. They were developed for the times. Oil technology has improved many times since those oils were prescribed in the service manuals years ago.

Factory oil recommendations were not "written in stone"; they were written on paper.
 
So how much zinc is in regular SAE 10W-30 oil??? The whole zinc amount is another controversial topic that comes up.
ZDDP, (Zinc), is good for engines and before the advent of catalytic converters was a common component of all packages contained in nearly every automotive oil,, full stop. ZDDP is unfortunately bad for catalytic converters. As a result, oil blenders formulate modern passenger vehicle oils with low or no zinc in em. Diesel engines and air cooled engines are notable exceptions. Rarely do these have CATS. Ergo Diesel and air cooled engine oils are still blended with significant amounts of ZDDP in em. As has always been the case, ZDDP is good for engines. Harley Davidson owners are aware that HD recommends that when top up oil is needed and no prescribed motorcycle oil is available a diesel engine oil rated CH-4, CI-4 or CJ-4 may be used. Harley Davidson does not recommend the use of regular automotive oils as a substitute. This seemingly odd preference by HD appears to be predicated on the fact that diesel engine oils are available in suitable viscosities and contain plenty of zinc.

To answer your question, "it depends". Read the label. An oil blended specifically for your mower, ATV or motorbike likely contains significant zinc whereas a regular automotive oil will contain less or maybe none. Some motorcycle oils tell you how much zinc they contain per my post above.

The take away, IMHO, is "don't" use regular automotive oil in your air cooled engines and don't extend drain intervals. ZDDP depletes over time and its protection vs the cost of a couple of lousy bottles of oil, (which you'll buy sooner or later anyway), is well worth the investment vs engine repair or replacement.
 
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I've followed the Geek and like his vids. That said, he pretty much concentrates on automotive applications. Lawnmower and power sport equipment, (air cooled), runs hotter and mostly don't have CATs which don't like zinc. Its also worth noting, IMHO, that oil viscosity numbers are temperature dependent and only are given for roughly the 104 F to 212 F range. Viscosity drops precipitously and rises exponentially beyond these range limits. Air cooled engines can reach significantly higher temps than 212. This may account for the higher viscosity oils they recommend for these..
Briggs and Stratton oil recommendation. In summer I suspect that it might get up to 110F in some places but people usually do yard work during the cooler part of the day. One thing for certain as some post - keep the engine clean of debris so it gets good air cooling.

Oil_rec_chart_smaller.webp
 
Why pay top dollar for oils by Kohler, Briggs, or Kawasaki. You can get Mobil 1 15W50 at Walmart in a 5qt. jug.
 
It's crazy (to me) what people pay for "equipment branded" oils, but they are brand loyal especially if it involves the illusion of "free" warranty repairs.

Truth be told, no equipment manufacturer makes their lubrication products, they just purchase large quantitates of oils and greases from the petroleum distributors who package it under "private label" contracts. The labeling and packaging are what people pay the extra money for. Usually that is a higher cost percentage than buying the petroleum manufacturers brand

Equipment manufacturers are no in the oil business.

The only oil I refuse to use is recycled generic bottled types.
 
It's crazy (to me) what people pay for "equipment branded" oils, but they are brand loyal especially if it involves the illusion of "free" warranty repairs.

Truth be told, no equipment manufacturer makes their lubrication products, they just purchase large quantitates of oils and greases from the petroleum distributors who package it under "private label" contracts. The labeling and packaging are what people pay the extra money for. Usually that is a higher cost percentage than buying the petroleum manufacturers brand

Equipment manufacturers are no in the oil business.

The only oil I refuse to use is recycled generic bottled types.

Agree 100 % plus, truth be told, most "Brands" of consumer grade mowers are made by 1 outfit, namely MTD, ( Black & Decker ).

An argument in favor of opting for equipment branded oils, particularly during the warranty period, might be the warranty itself. My understanding is that in the US a manufacturer can't specify a brand to use under warranty unless they are providing it. Up here in Kanukistan we don't have that protection so are best advised to use the brand the equipment maker specifies until the warranty is up. This constitutes a catch 22 because most engine wear will occur during an engine's early life when a better oil might have saved tears later, after the warranty expired in any case.

As I write this I am ordering "Gravely" 20W 50 for my Hydro-Gear 3100 transmissions. Ariens does make their own mowers, ( Ariens owns Gravely ), and their branded oil specifies on the label that it is full synthetic & contains zinc. Their ad clearly offers that this oil " Replaces Hydro-Gear 72750 ", ( Hydro-Gear's branded oil product ). My machine is currently under warranty by both Ariens and Hydro-Gear as well as Kawasaki for the engine. For my engine, I'll stick with Kawasaki branded oil during the warranty. After the warranty period, specs alone will drive my choices. Price is a minor consideration IMHO as a case of oil of almost any brand costs a pittance compared to the value of the machine its going into. YMMV.

As a side note: It is worth noting that most consumer grade MTD mowers have "maintenance free" transmissions meaning they are designed to be "throw away" products from the outset. "Why worry about oils and filters when you can just go buy a new machine" ?

 
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Agree 100 % plus, truth be told, most "Brands" of consumer grade mowers are made by 1 outfit, namely MTD, ( Black & Decker ).

An argument in favor of opting for equipment branded oils, particularly during the warranty period, might be the warranty itself. My understanding is that in the US a manufacturer can't specify a brand to use under warranty unless they are providing it. Up here in Kanukistan we don't have that protection so are best advised to use the brand the equipment maker specifies until the warranty is up. This constitutes a catch 22 because most engine wear will occur during an engine's early life when a better oil might have saved tears later, after the warranty expired in any case.

As I write this I am ordering "Gravely" 20W 50 for my Hydro-Gear 3100 transmissions. Ariens does make their own mowers, ( Ariens owns Gravely ), and their branded oil specifies on the label that it is full synthetic & contains zinc. Their ad clearly offers that this oil " Replaces Hydro-Gear 72750 ", ( Hydro-Gear's branded oil product ). My machine is currently under warranty by both Ariens and Hydro-Gear as well as Kawasaki for the engine. For my engine, I'll stick with Kawasaki branded oil during the warranty. After the warranty period, specs alone will drive my choices. Price is a minor consideration IMHO as a case of oil of almost any brand costs a pittance compared to the value of the machine its going into. YMMV.

As a side note: It is worth noting that most consumer grade MTD mowers have "maintenance free" transmissions meaning they are designed to be "throw away" products from the outset. "Why worry about oils and filters when you can just go buy a new machine" ?

Any quality 20W50 oil will work in the Hydro -Gear 3100. Hydro-Gear doesn't specify what brand they use at the factory. They do say that any 20W50 will work. I'm currently running NAPA 20W50 in my Hydro-Gear 5400.
Heck, even Mobil 1 15W50 will work.
What is important is using hydraulic filters instead of automotive filters.
 
Any quality 20W50 oil will work in the Hydro -Gear 3100. Hydro-Gear doesn't specify what brand they use at the factory. They do say that any 20W50 will work. I'm currently running NAPA 20W50 in my Hydro-Gear 5400.
Heck, even Mobil 1 15W50 will work.
What is important is using hydraulic filters instead of automotive filters.

Thanx for that. I suspected there must be something different about the filters owing to their uncommonly high price. The Gravely kit I ordered does come with the Hydro-Gear branded filters. You mention "hydraulic filters". Are there brands of these which I can use to substitute Hydro-Gear filters in future ?

Addendum: OK, I think I get it. Hydraulic filters have a "check" valve in addition to the bypass valve. I see some on Amazon.
 
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