water in tranny

[galynd]

I just purchased a yanmar 3gm30f with a km3p transmission. Since I live in Texas and the purchase came from Rhode Island, I carefully checked out the boat yard and found them to be reputable. In fact as an act of good faith they only required 1/2 down and the remainder to be paid upon receipt. They also had a mechanic check it out and sent me a video of the motor running. Upon receiving it I've checked all fluids and noticed the tranny has water and emulsified oil. How could water have gotten into the tranny unless the motor was submerged? any thoughts? should I ship the motor back?

thanks, greg

 

[kenn]

The tranny is sealed, isn't it? ... so how could water get in? Just asking. Maybe they pressure-washed the engine and the filler/dipstick was loose...?

Get this all documented, first. Have someone trustworthy and knowledgeable confirm your finding of water. Ideally, with them present, you should pump out the tranny and examine to see how much water, whether the water is salty, etc.

The next step is to clean and refill the tranny with the right oil, and assuming there's nothing wrong with the engine, run the thing and look for any other problems.

 

[Ross]

My tranny is water cooled. If it were to freeze and break the water line I presume that it would leak into the tranny. It is on the suction side of the water pump so I would also have oil at the water pump. I think I would pressure test the water line on the tranny.

 

[Rick]

If the motor has been submerged in salt water, upon close inspection, you should be able to see telltale signs of corrosion even if it has been painted over. One would think you would also find signs of water in the engine oil although a change can hide that. The tranny is a seperate system and unlike Ross's boat, most likely isnt water cooled. The tranny itself could be an addon and if submerged in salt water, would also show it. If the motor is not already in the boat, why not rebuild the transmission or at least take it apart to inspect it. Change the oil and look close for any sign of metal ie rust flakes. Interesting delima.

Cheers

 

[Tim R.]

What did the boatyard say when you told them there was water in the tranny?

 

[galynd]

thanks for the info. I do believe this unit is not water cooled. The boat yard was oblivious to any water in the tranny. They believe it might have come from standing rain water after the boat sat on the hard. It was wrecked. they suggested it might be condensation but there was too much water for that. I've run a ton of oil through the unit and am going to take my chances. there seems to be no damage to the unit. thanks for everyones input.

 

[Chuckbear]

we had an oil cooler fail and fill the transmission with water and since we were unaware we did run it for a while like that. After several flushes with transmission oil until we were satisfied the water was pretty much gone, the transmission went on to still be working today, some 9 years later. Chuck

 

[Steve Dion]

Greg:

I would suggest that you run it for 10-20 hrs and then r/r the transmission oil again. These units are very well built and can take a lot of abuse.

Good luck!

 

[Witzend]

Is it possible that water has leaked from the engine coolant system somewhere, run down inside the bell housing, dripped on to the input shaft of the transmission and breaching the input seal? Seems unlikely, but stranger thing have happened. If you have not installed the engine yet, I would split the bell housing, look for water intrusion evidence, and inspect the damper plate as well. How many hours were on the engine/transmission?

 

[galynd]

it appears the unit did sit partially under water for a time. I base this on Non-obvious slightly rusted bolts and other items as I check out the motor. I believe the water entered he tranny through a tiny vent hole in the dipstick. It has a plastic cap with a tiny vent hole I discovered in flushing the unit with oil.

again, thanks to all for your input.