How many places for gear lube to go?

[ildoc]

1996 5.7L Mercruiser Alpha One. I've noticed a continuing, gradual loss of gear lube. As the boat's new to me, I changed the gear lube at the beginning of the season and it appeared fine, but refilling seemed to take less that the manual stated. <br /><br />After several days of running, the lube in the reservoir was down a little (an ounce or so) so I refilled it, only to have the same situation a few days later. Fearing water in the lube, I changed it again, and it appeared fine. The seal was missing from one of the plugs, so I replaced it, thinking that was perhaps my problem. <br /><br />But NO!! It continues to lose a little gear lube every several hours of use. Where is it going? If gear lube's going out, shouldn't water be coming in?

 

[Haut Medoc]

Re: How many places for gear lube to go?

It's probably leaking into the bellows through the yoke seal....Pull the drive and have a look...JK

 

[bigbrownbuku]

Re: How many places for gear lube to go?

are you filling the drive from the bottom plug?

 

[ildoc]

Re: How many places for gear lube to go?

Originally posted by BenC:<br /> are you filling the drive from the bottom plug?

Yes.....both times.

 

[Blitzen]

Re: How many places for gear lube to go?

I have had the same symptoms with a new (50 hours) 350 Mag MPI Horizon. Contacted Mercruiser and they said it might be the prop shaft seal....only loses lube when the prop turns. The only real way to diagnose is to pull it and both pressure and vacuum test it....no other way. This problem developed after I had the gimbal bearing replaced this spring due to a blown seal which caused water to be in the lower unit.

 

[ildoc]

Re: How many places for gear lube to go?

Originally posted by Blitzen:<br /> I have had the same symptoms with a new (50 hours) 350 Mag MPI Horizon. Contacted Mercruiser and they said it might be the prop shaft seal....only loses lube when the prop turns. The only real way to diagnose is to pull it and both pressure and vacuum test it....no other way. This problem developed after I had the gimbal bearing replaced this spring due to a blown seal which caused water to be in the lower unit.

What kind of setup does it take to pressure and vacuum test? Sounds like something a newbie such as myself wouldn't want to get into.

 

[Blitzen]

Re: How many places for gear lube to go?

M/C dealer or repair shop. Based on the little I know, this type of thing is for the pros with the right equipment and knowledge. That gimbal replacement was several thousand dollars ( paid for under warranty) You DO NOT WANT water in your drive.

 

[ildoc]

Re: How many places for gear lube to go?

Blitzen,<br /><br />Thanks for the head's up.