View Full Version : Transmission Fluid Change

05-06-2009, 12:49 PM
I changed the transmission fluid on my mcx350 6 weeks ago and have since put about 8 hours on the boat. When I pulled the cover on the center part of the floor there appeared to be a very minimal amount of oil mixed with water (it was more water than oil- which there is always a small bit of water with from going in and out of water). The dipstick appears to be at the full position and there is no oil leaking from anywhere around the transmission itself (in the rear of the boat). The boat is 3 years old and may be sluge buildup in the hull. My question is if there was to much oil in the transmission would the overflow occurr in the transmisson area (rear of the boat)?

Thank you

05-06-2009, 12:53 PM
If you overfill it, it can come out the breather

05-06-2009, 01:09 PM
where is the breather located and is that like a feature that will prevent any damage?


05-06-2009, 03:09 PM
A three year old boat shouldn't be facing leaking transmission seals yet, so it's unlikely that that's the case. I'm assuming that the transmission oil in your boat is 15w40 (as opposed to ATF).

I wouldn't worry about oily water in the bilge. Far more likely that it's from spillage the last time the filter was changed, and that leftover oil mixed with water to give that appearance.

My approach would be to monitor it. I'd carefully and regularly check engine oil level and transmission oil level. If neither are dropping, it's unlikely you have any kind of leak.

Another thing you could do is put several gallons of water in the bilge, throw in some kind of degreasing soap like 409 or Simple Green and take the boat for a ride down the highway...let the soapy water slosh around a bit, then find some place to safely and ecologically drain the oily bilge water...(into a five gallon bucket and take it to your oil-disposal facility, for example). This way you'd at least be starting from scratch in your diagnostic process...clean bilge, tranny and engine oil full. If more oil accumulates in the bilge or if oil levels drop...time to look for the leak.