Posted by Bill Wincapaw on December 19, 1997 at 17:51:51:
In Reply to: synthetic oil posted by T.KRALOVIC on December 17, 1997 at 20:04:09:
Here's my 2 cents worth; synthetic oil only beats petroleum base oils (sae) only under extreme conditions. All the testing between the two is to destruct levels which one of us drives our PW's to extremes. No oil will replace worn bearings and your only adding to those worn bearings when you run detergent oil in an eng with a bypass oil filter(does not filter oil to the bearings).Detergent oil holds dirt in suspension. Nondetergent lets it fall to the bottom of the pan. That's why you have a floating oil pick up strainer which draws the clean (settled) oil from the top crankcase. The engineers designed the flathead to run with nondetergent keeping its' advantages (and disadvantages) in mind. In closing I'm not against synthetics (some of my best friends are synthetic) I just don't see the advantage of putting any type detergent oil in a engine that doesn't have a full flow oil filter.
Best regards Bill