Small oil leak in engine compartment

[hopkinsonsa]

I am getting a very small amount of oil in my engine compartment when running the engine under load. While investigating where the leak might come from, I discovered I have a missing bolt where my KANZAKI KBW20-1 attaches to my Yanmar 4JH3E. Is this possibly where the oil is coming from? Anyone have any idea what size bolt I need? (I use Dexron ATF in the Kazaki so I doubt the fluid is ATF).

Many thanks.

[CrispyCringle]

A missing bolt should not cause a leak. There are only a few bolts designed for that (drain taps, etc). You ruled out a transmission leak with the Dexron fluid. Next you need a strong light (not a cell phone light) and probably a small mirror on a stick. Start looking around hose clamps and where components are bolted together. If you find a wet spot trace it up to the highest point. A leak will always follow gravity. If your oil is nice and clean, a small piece of toilet paper can be used to wipe a spot and see if its wet. Shows up easily on that kind of paper. Happy hunting.