Merc Bravo III pressure test

Does anyone have a procedure or experience pressure checking a Bravo outdrive? Mine is a 96 Bravo III and has a remote oil reservoir. I just replaced the drive shaft housing due to a broken cavitation plate and now I have an oil leak. I found a good (visually) used replacement housing with the same part no & shim stampings and then swapped all the internals. I did change o rings, bellows, gear oil hose, & shift cable. I'm leaking a full reservoir about every 45 min of runtime, no or very little leakage when not running. No external evidence of leakage with the boat in the water, i'll pull it out tomorrow. I have some leakage in the bilge but not enough to account for all the oil I'm losing. I can't really get to or see the thru transom gear oil fitting in the engine compartment, too cramped. Any help woiuld be appreciated. Thanks

I noticed that you have changed the bellows, from past experience I would say the gear oil is leaking due to the plastic end that has snapped off the gear oil through transom fitting. So easily damaged whilst doing the bellow change, they used to be made of brass but in there wisdom they changed to plastic. Once the boat is off the water it should be easy to see the leak. Hope this helps.
Jim

jimmfnd said:

I noticed that you have changed the bellows, from past experience I would say the gear oil is leaking due to the plastic end that has snapped off the gear oil through transom fitting. So easily damaged whilst doing the bellow change, they used to be made of brass but in there wisdom they changed to plastic. Once the boat is off the water it should be easy to see the leak. Hope this helps.
Jim

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That was my first thought too, but I pulled the drive and found the bellows full of oil. There wasn't any leakage at the gear oil fitting on either side of the transom. So my leakage appears to be from either the o ring around the driveline carrier assembly or the driveline oil seal. The seal looks ok to me but there's a little scarring on the yoke stub sealing surface. The carrier o ring is flattened out and hard. I'm going to replace the o ring, seal, and yoke stub and hope that takes care of it. Anything I'm missing? Also I did pressure check the drive while still installed by pinching off the hose at the oil reservoir, held 10 lbs overnight.