bravo III milky oil but holds pressure for days

2004 searay

Seaman Apprentice
Joined
Jun 30, 2023
Messages
42
i am trying to locate the cause of the milky oil in my bravo drive. i have had the pressur hold steady at 12, 8, 4 and 14 psi . each pressure held with no drop . ive been working on this for over a week and cant figure out how water got in. im about to just change the drain plugs and gaskets and call it a day. very frustrating.
im waiting on a vaccum gauge to try those pressures. .
 

alldodge

Moderator
Staff member
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Mar 8, 2009
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42,227
Was it all milky as in a lot of water or just a little? If just a little then there might have been something that got next to the seal causing it to leak. Then after a bit of running it stopped.

Could put 2 to 3 in of vacuum on the drive and try to see if it holds. If drive gets real hot (many B3's do), when it cools down it can draw in some water. Is outside of drive white and chalky?
 

dingbat

Supreme Mariner
Joined
Nov 20, 2001
Messages
16,129
Never had luck reusing drain plug seals. Install new seals every time I open the drain plug

Seals leak in a Vacuum long before they leak under pressure
 

muc

"Retired" Association of Marine Technicians...
Joined
Jul 7, 2004
Messages
2,154
Ayuh,..... Have you been turning the shafts, while under pressure,..??
At Merc school they teach us "push-pull. wiggle-wiggle, turn-turn and shift-shift anything that moves".

Remember that the drive must be completely drained during testing.

Very important! Have you pulled the drive to check for water in the bellows?

The first couple of years of the Alpha One Gen2 we needed to stand on the prop shaft to get them to leak, so maybe you're not using enough force during testing?

I've had more then a few that would pass pressure and vacuum tests no matter what I did, but are still getting milky oil during use. At that point all you can do is disassemble and look for the grease between the seals to be "washed" out. If that's the road you have to go down, Start with the prop shaft seals.
 

alldodge

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Mar 8, 2009
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im not sure what you mean by that. the oil is contaminated, its not supposed to be that color, the oil installed was darker. blue/green tint
Meaning there may have been something that caused the seal to leak, piece of fishing line or other. It moved away from seal and all good

MUC is the guy to pay close attention to what he says
 

racerone

Supreme Mariner
Joined
Dec 28, 2013
Messages
37,978
Install a seal kit now.-----Cheaper than gears and bearings.----Seals wear out and could be half worn now.
 
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