why is there oil in my bellows but pressure test holds 15psi overnight

[2009 stingray]

i pulled the drive on my boat and there is oil in the bellows, lots of it. i drained and pressure tested the drive and find no leaks. could the drive be overheating and pushing the oil out of the input shaft seal? bravo3 drive,

 

[alldodge]

Try putting 5 to 7 psi in and rotate the drive shaft. Also try to move it up/down/side to side to see if you loose pressure.

With a lip seal, the more pressure is applied the tighter the seal is forced against the shaft

If all that works without leaks, try a vacuum at 3-5 inHg

 

[Scott Danforth]

Agree with AD, turn the shaft with pressure

 

[pae0332]

agreed, drop pressure to different levels

 

[nola mike]

I mean, only place for it to come from is the input shaft seal, right?

 

[Pmt133]

I've seen cheap grease look like lube in the bellows too. Flung and burned down from the gimbal and u-joints.

I agree with the movement and vacuum tests though. That usually will show a weak/worn seal. You losing lube in the reservoir?

 

[Chris1956]

Look at the sealing surface of the yoke. If there is a groove, the seal will leak. Replacement will be in order.

 

[Lou C]

Smell what you found there. Because if you have a grease-able gimble bearing sometimes the grease will separate out in a runny discharge. If it doesn't smell like gear oil it could just be that.

 

[pae0332]

I've seen cheap grease look like lube in the bellows too. Flung and burned down from the gimbal and u-joints.

I agree with the movement and vacuum tests though. That usually will show a weak/worn seal. You losing lube in the reservoir?

sealed bearing, no grease on bravos

 

[alldodge]

sealed bearing, no grease on bravos

Don't see it being grease, that said the new bearings are sealed but there are thousands of the old style still out there that get greased

 

[Lou C]

boat's a 2009, did they start using sealed bearings that far back?
Agree with turning the shafts when the pressure and vacuum tests are done. I just had to replace the water pump seal on my OMC Cobra (these have the impeller driven by the end of the driveshaft and there's a seal that keeps water from getting in the gearcase. Found it that way, had to turn the shaft. It's a common leak point on the Cobra design because of the close location of the impeller and the driveshaft where it comes out of the upper gear housing. A place up in Canada (TC Electronics & Marine) sells a modified water pump plate that has 2 seals on it, which makes up for any wear on the shaft where the original seal rode. I installed one of these and will see if it solves the water in the gear oil I was seeing the past few years. The only way to get this plate off is to tap 3 holes and push it off. After that the job's easy. There are 2 o rings on the plate, the smaller one was totally disintegrated so that might have also been a source of the leak.

 

[Scott06]

boat's a 2009, did they start using sealed bearings that far back?

yes by 2009 they were sealed on new ones.

My 2003 was still greased I think 2008 ish was cut over. Would entirely depend on when the power pack was manufactured instead of boat year. My engine was built in june 2003 , installed in 2004 boat