I have a Yanmar 2GM. The manual calls for a little over 2 quarts of oil. The full mark on the dip stick is Probably a quart higher than two quarts would register. The PO's ran it at the two quart level. I called the Yanmar dealer hip and they wouldn't say anything without looking at the motor (of course). I've been running it at the higher level without a problem thinking that more oil (within limits) is better. Another guy with the same motor told me he does the same. I assume the mechanic who did the installation (replaced an A 4)probably determined the high mark and should have the last word. Thoughts?