Dissapearing Bravo three gear lube

[Leardriver]

Hi all!

I am cleaning up a boat with a Bravo Three that seems to use gear lube. It is an '02, drive serial 0m1444xx, with less than 150 hours on it. It went through half a reservoir full in 5 hours of use.

It does not seem to have water in the lower unit, tested by removing the lower drain plug on the drive. The plastic reservoir inside the engine compartment does not have water in it. The bilge is spotless, certainly no sign of leaky lines.

I've heard about this before, and just can't find the threads. Is there an internal seal that goes bad, and spits the lube out into the water? How to test or verify? Cost to repair?

Thanks as always for your suggestions.

 

[Don S]

Re: Dissapearing Bravo three gear lube

Did this happen just after a gear lube change?

 

[Leardriver]

Re: Dissapearing Bravo three gear lube

It is my friend's boat, and a new acquisition, so I don't know. I'm wondering if there was an air bubble due to a sloppy fill procedure, and it just purged and now has the correct level. I topped it off, and will watch it closely.

He took it out three times in a week for about 20 minutes each, to test props, etc, and it never moved from full. Then, all of a sudden, half of a reservoir down. He's hoping for a bubble.

 

[Don S]

Re: Dissapearing Bravo three gear lube

They always get an air bubble in the top of the drive, even when filled correctly. It may take a while to "Burp" that air out. Best thing to do is top of the gear lube and watch. It should stay full if there is no leak.

 

[Leardriver]

Re: Dissapearing Bravo three gear lube

I appreciate the advice. I hope you're right.

I've been reading about Bravo Three gear lube loss, and it sounds like a big problem.

 

[Don S]

Re: Dissapearing Bravo three gear lube

I've been reading about Bravo Three gear lube loss, and it sounds like a big problem.

Funny, I was a Mercruiser tech for a lot of years and never heard that. Not many people post and say "My Bravo 3 doesn't leak.

 

[Neskahi]

Re: Dissapearing Bravo three gear lube

Funny, I was a Mercruiser tech for a lot of years and never heard that. Not many people post and say "My Bravo 3 doesn't leak.

What is the actual cause for loss of the gear oil? My 96 Bravo III lost gear oil from day one new,until I started leaving
the reservoir cap a little loose after reading about the following theory. That is that the Bravo's do run hot while on long cruises and up on plane. The oil heats up and expands and is forced through the seals because the reservoir cap has a check valve that lets air in but not out. Just trying to understand this phenomena of disappearing oil.

 

[Don S]

Re: Dissapearing Bravo three gear lube

Welcome to iboats Neskahi.
You should really start your own thread with your question.

 

[HT32BSX115]

Re: Dissapearing Bravo three gear lube

Mine doesn't lose oil.

If yours continues to lose oil, it's leaking out from somewhere.

After you refill any drive it will "burp" for quite sometime. Mine did it for 3 or 4 hours of run time the last time I did a drain/refill.

It eventually stopped.


Cheers,



Rick