Oil in the Bilge

[Scott]

I'm a new CAT30(84) owner, I've experience no issue with the universal 21hp and am quite impressed with her reliability and performance. However after a extended down period I noticed oily substance in the bilge. I checked the oil level and did not notice a decrease in the oil level. Could this be transmission fluid? Is this normal run off behaviour when she sits for an extended period of time?

 

[Richard]

Breather Hose

Check your breather hose coming off the top of the valve cover. I had the same problem until I ran the end of the hose back into the air cleaner intake. No oil in the bilge after that...

 

[Randy]

Drip when checking oil

Sometimes when checking my oil (Universal M-18 diesel) a drop falls off the dipstick before I can get a towel under it (due to the tight clearance around the dipstick hole). If not wiped up quickly, these drops will work their way into the bilge, making things messy. Don't know if this is contributing to your problem...good luck.Randy

 

[James]

Oily substance in your bilge

Could be diesel. What color is the oily stuff?By your model year, your fuel tank could have corroded thru. Common problem.

 

[Pete]

Trans

Put some of the oil on a white 3x5 card and check the color against the other fluids(engine oil, fuel & trans fluid). That will help you narrow down the search area. Also, get an Oil-Sorbent sheet fron West Marine and slide it under the engine & trans. It will further narrow down the search area. The drain plug on the transmission has a aluminum washer that tends to develop small pin holes.Good luck.