....snip....
back to the 5w20 thing, these engines only turn 3800 rpm's
to the oil school guys (me in that boat) 5w20 is what almost all new cars say run, its the way to go

Again I repeat the tolerance are larger in an air-cooled engine.

How many Air-cooled V-twin motorcycle owner run 5w-20?

Show me some used oil analysis of any 5w-20 oil and compare them with most any HDEO 15w-40 when used in a Kawi V-Twin air-cooled engine or similar popular engines.

If you can show me lower wear metals in the analysis.... I just might be convinced.

 

back to the 5w20 thing, these engines only turn 3800 rpm's
to the oil school guys (me in that boat) 5w20 is what almost all new cars say run, its the way to go

That helps them get better m.p.g to help them meet EPA reg's.

All this talk about oil ! What works well in a car or a jet plane does not mean that it should be used in a air cooled motor that is on a mower.

About the non-detergent oil in motors without a filter ..... thats hogwash ! :laugh:

 

anyone know what weight engine oil nascar guys use on race day???? i used to be a thick oil guy but truth is the thin stuff is better. there are not to many points one can make to say a 10w40 or 15w40 has any advantage over a 5w20 or 0w30 the only advantage to a 10w40 or 15w40 is its burn off temp is higher thats it but as long as your engine does not burn oil there is no need for thick oil. just think of when u have a stuck bolt what do u spray it with? pb blaster or liquid wrench not 10w40 oil.
as for synthetics or regular oil, i prefer a blend that way u get the good of both but no, if you tear down a synthetic oil engine and regular oil engine and check and measure everything there was no difference. i seen it with 10 taxi cabs with over 100000 miles on all of them nothing different
back to the 5w20 thing, these engines only turn 3800 rpm's
to the oil school guys (me in that boat) 5w20 is what almost all new cars say run, its the way to go

 

The part I like the most around people racing or other business is when someone says WHO TOLD YOU THAT. Been around alot of equipment, racing, farming and mowing. Seen alot of mtrs apart. There is a big difference believe me. Alot of trans in big trucks now have a million mile war if you use their syn oil. And if you think any NASCAR team doesnt run syn oil in their mtr, trans and diff. Your on some pretty good koolaid.
Gandpa used to say believe 1/4 what you read, 1/2 what you hear and all what you see.

 

I wish I had the link to the study done comparing SA oil to modern SJ + detergent oils. It is on www.bobistheoilguy.com The pictures are dramatic. SA oil is a disaster oil. Maybe I will spend time looking for it - maybe not.

Now back to 5-20w oils. Sorry I would not use any 5-20w oil in any air-cooled engine. However I'm sure it would be vastly better than a low end SA oil. Fuel economy at the expense of the possibly greater wear with a 5w-20wt oil? No thanks. The 20wt oil IMO just doesn't have the film strength to properly do it job as intended. Air cooled engine have larger tolerance than water cooled.

In place of straight 30wt in air-cooled engine I prefer to use a diesel rated oil such as a 15w-40 or better yet the synthetic version in a 5w-40 wt. Mobil 1 15w-50 is fine as well.

The thinnest oil I would go in air-cooled engine is Mobil 1 High Mileage 10w-30 and Castrol Syntec 0w-30 "European Formula" made in Germany. Both of these oils especially the Syntec is really a higher viscosity than a standard 10w-30 oil. Closer to a 35wt. Great oil for motorcycles even.

If you don't believe me take the time to read up on it yourself at the web site mention earlier.

If I found out someone was using SA oil in any used piece of equipment that I was considering buying I'd run. One of many reason I rarely buy used power equipment.

 

Have run 15-50 Mobil One in everything. Tiller, push mower, psi washer, Scag TT etc.
Ran a 720 grasshopper with 20hp k to 2000hrs and still didnt use oil. Have never had problems also keep air filter clean. Ran about same weight oil in my race mtrs and no problem there either. Think it is a better choice for air cooled. Dont think Mobil One is a true syn but a true syn oil will not break down like regular oils.

Mobile 1 is a true synthetic oil. One of the best and well regarded oils made. Pricey but worth it. I use Mobile 1 0-40 in the Audi and the Benz. Mobile 1 5-30 in the trucks. Mobile 1 10-30 in the Walker and Exmark with Liquid cooled engines. I run Opti-4 in all air cooled machines.

 

And remember (almost no one does) if your engine does not have forced lubrication (no filter) you need to run NON detergent oil.... and there are NO synthetics with that property. The detergents suspend fine particles in the oil so that the filters can trap more of them. great for machines with forced lube but very bad for those without.

I totally disagree so far. I have a Techumseh 6.5 HP on a 22" Toro Recycler and in the manual it calls for: Synthetic oil at: 0w30 for temps below 40 degrees F, and straight 30wt at temps above 40.

The main point is that it is clear in the manual: " Be sure the container is marked A.P.I. Service SL/SJ.

Techumseh engine operators manual, 181-1215-14 page 4

That means that a non-filtered engine is calling for a high detergent oil and synthetic no less at lower temps for better flow.

Anyone reading this, DO NOT use non-detergent A.P.I. SA oil, this oil in not for engines made after the first years of internal combustion. It will damage your equipment.

 

Now this is something I have never heard before.

Well then you have a learning opportunity!

Before people quit paying attention and actually "learning" instead of paying attention to "ad hype" it was pretty common knowledge. AND I just pulled out a manual on a 8HP briggs and it clearly specifies NON detergent oil.

Most folks can't look at a bottle of oil and understand the SAE specs anyway....the manuals usually give you a SAE spec, those little two letter codes DO actually mean something.

Maybe only us "old" guys ever pay attention to those pesky little details that make huge differences. Most guys see 30wt and ignore everything else.

I used to love the synthetic commercial where they "fried" the oils in a pan.... so freaking what? The inside of your engine will never reach that temperature unless it has NO oil in it.

Now 2 cycle synthetic oil is whole different animal.... no way you should use anything else but that's because of the lower carbon and ash build up more than anything else.

 

And remember (almost no one does) if your engine does not have forced lubrication (no filter) you need to run NON detergent oil.... and there are NO synthetics with that property. The detergents suspend fine particles in the oil so that the filters can trap more of them. great for machines with forced lube but very bad for those without.

Now this is something I have never heard before.

 

Man was I way off, just popped myself on the forehead and got me a V8.

 

If you have every seen a engine run on regular oil and one run on syn tore apart you wouldnt say that. There is a difference. Ran a 540 BBC on 20-50 penn. Looked good never had trouble, bearings always looked good. Became a VP fuel dealer and started using 15-50 Syn VP oil. Mtr looked new, bearings looked new, crankshaft did look new.
Any race engine out there NHRA, NASCAR are run on syn oils, why? they are better.

I have seen both. No difference if the oil was changed as specified.

Race teams run the oil of thier sponsors, some are synthetic some are not.

Most car and engine manufacturers will even state that synthetic oils are not necessary. Futher many now state that even if you do run the synthetics you MUST follow thier oil change schedule, NOT that of the oil maker.

Nothing wrong with synthetics, just a waste of money in any non-high performance application.

Further, check your facts... many NASCAR teams run petroleum oils.

Heat and friction wear out oil. That's why small engine mfgs. require oil changes more frequently than automobiles. they run at higher temperatures (air cooled engines)

IF you follow the engine mfgs. change schedules the only difference in synthetic vs petro oils is in your wallet.

There have been dozens of research projects on this subject and no independent study that I'm aware of has ever stated that synthetics give longer engine life.

The problem with our engines is as I stated earlier they run at a slightly higher temperature. Thus the more frequent oil changes.

Synthetics give better lubrication under high loads and high (higher than normal is the key here) temps.

The temperatures where synthetics show better safety are well outside the normal operating temperatures of the engines we use.

So if you want to supercharge your mower and turn it 8,000 rpm then yeah buy some synthetic oil. Other than that the good old petro will do just as well.

And remember (almost no one does) if your engine does not have forced lubrication (no filter) you need to run NON detergent oil.... and there are NO synthetics with that property. The detergents suspend fine particles in the oil so that the filters can trap more of them. great for machines with forced lube but very bad for those without.

 

If you have every seen a engine run on regular oil and one run on syn tore apart you wouldnt say that. There is a difference. Ran a 540 BBC on 20-50 penn. Looked good never had trouble, bearings always looked good. Became a VP fuel dealer and started using 15-50 Syn VP oil. Mtr looked new, bearings looked new, crankshaft did look new.
Any race engine out there NHRA, NASCAR are run on syn oils, why? they are better.

 

If you're changing your oil at the recommended intervals there's no benefit to running synthetics'. Just a waste of money.

Run what the engine mfg suggests and keep it changed.

I concur with that.

 

If you're changing your oil at the recommended intervals there's no benefit to running synthetics'. Just a waste of money.

Run what the engine mfg suggests and keep it changed.

 

Have run 15-50 Mobil One in everything. Tiller, push mower, psi washer, Scag TT etc.
Ran a 720 grasshopper with 20hp k to 2000hrs and still didnt use oil. Have never had problems also keep air filter clean. Ran about same weight oil in my race mtrs and no problem there either. Think it is a better choice for air cooled. Dont think Mobil One is a true syn but a true syn oil will not break down like regular oils.

 

Yeah but you gotta be really tuned into your engines

I could swear at times an engine runs rapier on thinner oil, but then as was said I can't say
I see a real difference on fuel economy so one has to wonder if I'm imagining things.

Now those of us old school don't run much thinner than 10w-30, that's all I run thou my bmw calls for 5w-30 and uses that,
now the really old school guys won't go thinner than 10w-40 and there's no exceptions, then a few out there won't go below 15 weight.

There's something to it, I believe it has to do with longevity, and it takes years to see that but it might be that
engines don't last as long running thin oil, now I don't know because I don't expect mine to last 20 years heheh...

 

10w30 mobile synthetic in the gas engines
15w50 mobile synthetic in the hydro pumps
5w40 rotella synthetic in the diesel

I don't pay that much attention to the fuel economy in my mowers...there real good already. (probably get chewed out for that)