Bravo 3 losing oil?

[IanFS]

Hi guys

A couple of boating pals have Regal 2250 Mercriuise 350 Mag Bravo 3 and Crownline 250CR Mercruiser 350 Mag, Bravo 3. They both have to regularly top up their Stern Drive oil reservoir's at similar rates.

Now they are not showing signs of oil leakage at rest that is no oil films on the water, neither is there any sign of a seepage around the seals or joints and no water in the oil either???

Oil just doesn't evaporate, plus it won't be burning it as it's a stern drive.

Therefore has anyone had similar, is it normal, or is there a blow by factor with any of the seals?

 

[alldodge]

Hi guys

A couple of boating pals have Regal 2250 Mercriuise 350 Mag Bravo 3 and Crownline 250CR Mercruiser 350 Mag, Bravo 3. They both have to regularly top up their Stern Drive oil reservoir's at similar rates.

Now they are not showing signs of oil leakage at rest that is no oil films on the water, neither is there any sign of a seepage around the seals or joints and no water in the oil either???

Oil just doesn't evaporate, plus it won't be burning it as it's a stern drive.

Therefore has anyone had similar, is it normal, or is there a blow by factor with any of the seals?

It's not normal, the bad news is the seal is leaking, the good news is water is not coming in. The B3 has either two separate seals per prop shaft (Items 37 and 42). or has one double seal per prop shaft (Items 36 and 41). The new style is the double and is said to fix the leaking issue.

I replaced the seal on my B3 with the double style and have not have any issues. That said I just picked up a new direct from Mercury and the inner shaft seal was leaking. Covered under warranty but it still seeps ever so lightly.

 

[IanFS]

Thanks Alldodge. It sounds like this is a general problem with the Bravo 3, is that right?
I wonder if there is a Bulletin on it somewhere?
Have you heard this is a general issue?
Cheers

 

[alldodge]

Thanks Alldodge. It sounds like this is a general problem with the Bravo 3, is that right?

Yes it's a known problem but the new seals are supposed to fix it.

I wonder if there is a Bulletin on it somewhere?

Fun Times in another post listed Service Bulletin Number 2010-64, but I'm unable to find it.

Have you heard this is a general issue?
Cheers

I have with the old style seals but not with the new. As before I installed the new seals in my old drive and have not had an issue, but my new drive (not yet been in the water) was leaking real bad. After the dealer repaired it I still found a small leak which noticed it stopped a couple days ago. Don't know if they just put it under pressure and left it there for three days or replaced and pressure tested for three days. You can have a leak and when air pressure is put on the seal the pressure helps it seal, the more pressure the tighter the seal goes against the shaft.