Stormin Mormon wrote:
For air cooled engines, it's important to use a good quality oil.
Air cooled engines run hotter than liquid cooled. My fav is
Castrol. So a good name brand is more important than the S
rating. Other good brands I like are Penzoil, Mobil, and Exxon.

Any engine needs a oil of at least the quality specified...air-cooled or no.

As for the name on the can, if it meets a specified API/SAE grade, it
meets the grade. The rest is advertising hype for the most part.

That said, there are a few oils I _won't_ use -- QS is one. No way to
prove it really had anything to do with it, but I had a Chevy 350 throw
a rod w/ it -- when opened it up, the top of the head was 2 inches deep
in sludge and blocking the oiling holes so it wasn't getting any oil at
all down no's 7 & 8 and the rest were ready...never overheated, always
changed on schedule, etc., etc., ... But, at 50k, it had to have
complete rebuild. I've run those engines routinely for 150k or more and
that's the only one ever to have had an early failure.

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