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Quote:

Originally Posted by Fast Algae (Post 2639613)

There were a few drops of water in the pan, but there was some in the nooks and crannies of the drive (ran it last night).
I am checking into someone pressure/ vacuum testing it.

What can happen if you pressure test it , is it will check ok.
And as soon as the drive is under load it will leak.
Because now the propshaft moves back because of the prop pushing water.
It can also be a hair crack in the housing and under load it is opening up, but on the bench it holds the press ?!

I had that happening to me once.

Quote:

Originally Posted by daredevil (Post 2639596)

Hey Chris,
we finaly agree on something . LOL:drink:

I'm sure we agree on lots more ;)

Quote:

Originally Posted by Chris Sunkin (Post 2639583)

As you should be. One-way leaks on drives are very rare. Low reservoirs are a major red flag. Find the leak and fix it, before you're buying gears, shafts and cases.

In 17 years of using Bravos, every single one I have run had the mysterious disappearance of gear oil. A table spoon per hour is about what I see too. I never found any water in my oil which has ranged from merc, to penz, to now Royal Purple. They don't leak on the floor, and I can usually trace bilge spillage to the reservoir cap vent.

I always attributed it to burping, boiling, etc.

I have had brand new from the factory drives use that much. I would be concerned enough to give the drive oil system a thorough inspection in an attempt to locate the leak. Once found the leak in the resevoir itself. A small crack where it slides onto the bracket. That said I would not freak out, drive it and keep a close check. Look into the hatch every time you shut the boat down and continue to look for evidence of leakage.

Fast,
Is this an XR drive. If so the early ones had a problem retaining the seal in the upper retainer nut, right behind the input shaft yoke. If you pull the drive and find fluid in the bellows, it is the seal.
If a standard B1, they dont make as much heat so no a problem. The XR's creat a great deal of psi when running, due, I suspect to heat build up.
Are your running a drive shower? If you are creating enough heat and psi, it can and will push drive oil out through the propshaft seals. At least that is the way it has been explained to me. After install a good drive shower a lot of times the usage will stop. Make a pass and stop the boat, go back and put your hand on the drive see if it is hot. It will coold down quickly once the drive is in the water, but one time I was riding with a friend, a couple of hard passes. No drive shower, I went for a swim and when I climbed back into the boat I used the drive as a ladder, I could not believe how hot that drive was!!
Definitely pull the lower drain plug and look for water. If there is none.. the oil could be going out past the propshaft seals and when it cools down psi is reduced and no water entering the drive.. The level goes down and you add more to it.
Propshaft should have preload on the bearings suporting it, it should not move in or out or up or down. If it is moving, it has lost it's preload then it also can be a source of a leak.. and indication of more internal problems.. that must be looked into.
I psi test the drive off the boat at 15psi for at least 24hrs. A pin hole leak can take a while to bleed off and under load it may be excellerated. If you see no signs of oil in the boat interior, then you can assume the line to the bottle and bottle are ok.
Hope these ideas help in your search.
Dick