Water-thin oil like 5W-20 will let an older engine beat itself to death. It's designed to squeeze its way into microscopic clearance areas on modern engines. That's exactly the wrong apporach for engines like the old stovebolts and the ones from the 1960's and 70's with more "normal" clearances. Try puftting a drop of thin oil like 3-in-1 in the palm of your hand and pushing with a 3 pound hammer from 1/8" away. Then back off and take a hard swing from 6 inches. Then try the same test with a 1" thick layer of wheel bearing grease. Repeat as required until the light bulb in your brain comes on!
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!