Stern Drive Oil Leak

"Ok now I am PO'ed.....spe

"Ok now I am PO'ed.....spent a bunch of cash for a new outdrive and now here it the holiday weekend and I still have the same nagging oil leak from my outdrive.

Ok....count to 10,.,.,.,no may be 20.

Hope you guys can help me figure this out so I can get one up on the shop that told me that buying a new outdrive would fix my problem.

Here is the story. Outdrive oil leaks out the input shaft seal, into the bellows, add oil until it comes out into the bilge. I can run about 20 to 30 miles before getting an alarm that tells me my oil monitor is empty. This started with a 3 year old Bravo II and I had numerous seals replaced and even had the input shaft replaced. Now I did up grade to a Bravo III when I changed the drive and 1st trip out 25 miles out on the Gulf Of Alaska my monitor is out of oil. Refill and I now have oil in my bilge which means my bellows are now full. The drive was filled by the book.(fill to vent, replace vent screw, push about an inch into the monitor) I even pulled the boat out of the water and did it again myself still have the same problem. Checked the hose but not finding anything. Even changed that little plastic ball thingy.

<font size=""+1"">Please Help</font>

Sorry about the rant but between parts and this new outdrive I am close to 10 grand into this problem."

"I don't have experience w

"I don't have experience w/a Bravo drive but your problem sounds like an "O"ring, gasket or a seal is missing or installed wrong. Is there a seal missing between the OD and where the oil reservior meets the OD?"

The only way to be sure of exa

The only way to be sure of exactley where the leak is comming from is to have the outdrive pressure check with no gear oli in it.

I do not belive there is a spec for how much pressure to pump it up to but I use the OMC spec of ~17 psi.

I typically pump them up to 15 psi and see if it holds.
'
The normal merc outdrive produces ~ 7-9 psi when running so 15 is a solid check.

If you can have this done or do it your self this will tell the you what is going on and if it is in fact the upper carrier seal or an oring.

There is a good possibility that it could be the shift shaft seal or some other orings in the upper gear case.

The only way to tell is a pressure check with the out drive off the boat. If it is done while attached to the gimbal housing then the gear lube resovoir line has to be pinched off.

"Hello,
i have a 99 bayliner,

"Hello,
i have a 99 bayliner, 7.4efi / bravo 3 that is leaking gear oil in the bilge area under the motor. it is not coming from the gear oil resevoir or the resevoir line to the outdrive. Is this a outdrive seal problem or a more serious problem???"

"[IMG][url=""]http://i57.photo

"
Need to have a good yoke sealing area(not grooved) and seal to keep the oil in the drive and not in the boot."

BT DOCTOR

He had the yoke r

BT DOCTOR

He had the yoke replaced........I think he is refering to that as the input shaft. they sold him the whole ball of wax.......

Also you can press the seal when installing inside the carrier to a different depth to grab new surface area when installed on the yoke....:>)

"[IMG][url=""]http://i57.photo

"
Could it be leaking from the oil valve and dumping into the boot area? The gasket shoud seal it ,but?
oil in the boot is either a seal,yoke or some type of crack, or leakage from the oil valve.
could that "O" ring seal be damaged or the wrong size allowing oil to leak past the valve?"

"Ok...now that I am home I can

"Ok...now that I am home I can more easily provide info.

As stated in my 1st post. I had this oil leak with a Bravo II installed. Last season we put 3 yoke (input shaft) seals in and even did a yoke and seal change. First trip out this year after the install of a new seal it leaked oil. It was pressure tested the with no issues before reinstalling on the boat. After 20 miles the monitor bottle would empty, refill and shortly after that I would get oil in my bilge area. It fills the yoke bellows with oil(and oil only) and eventually pushes past the gimbal bearing into the bilge. I am running the recommended HP Merc oil. This has been an on going problem for 3 years.

The big problem now is that I have switched to a brand new out of the box Bravo III and I still have the same exact oil leak. WTF!!!!!!


BT Doctor.....if you are talking about part number 24....I would guess not likely. But then again who would think I would get the same leak with a totally new drive???


Sal that's the problem I am having but it just won't go away. Hopefully a yoke seal change for you will solve the problem."

"more like #25.What about a cr

"more like #25.What about a crack in the gimbal housing , factory defect????????????"

Change those every time I have

Change those every time I have had it apart. No cracks I have even check under some high intensity lights.

Try repressure checking with t

Try repressure checking with the outdrive while it is in place and the line near the resivior pinched off in order to pressurize the checkball fittings and associated tubing and the housing all at the same time. You have to pinch the line near the bottle because the bottle is vented.