OMC Cobra Leak

[Frozen]

My 1988 OMC Cobra took in some water last season and when I pulled the drive to winterize I had a lot of outdrive oil in the driveshaft bellow.

So today I started working on find the leaks, I assume there is a leak letting water into the outdrive and another leak letting the outdrive oil into the bellow. So I pressure tested the drive at 3psi and over about 10mins it would lose pressure. Pressurized it again and sprayed the whole drive down with soupy water, I found no bubbles anywhere. I repeated this and no luck. The drive has to be leaking by where the driveshaft goes into the drive but no bubbles around there either.

Any tips or specific places to look for leaks on the cobra? My next try would be to stick in a 55gal drum and fill it with water and pressurize it. But just thinking about that makes my back hurt.

Also I tried to move the shift lever/rod/shaft by hand and it was very very very hard, I never did get it in gear. I had a hard shift issue last season, any idea on how to fix that? The shaft does look a little dirty/corroded.

 

[a70eliminator]

Re: OMC Cobra Leak

The most probable way for gear lube to get into the bellows is out the driveshaft seal. Where did you find water? You should go a little higher than 3 psi and check close around the propshaft seal and also the fill plugs and dipstick are known to leak both will put water in the drive. A leaking driveshaft seal won't let water in the case unless the bellows are bad too.

 

[Frozen]

Re: OMC Cobra Leak

The bellows were good. And I found the milkshake mixuture everywhere in the drive when I drained it. I will go a little high and check those spots.

Thanks!

 

[Lou C]

Re: OMC Cobra Leak

If the bellows were good, and you got gear oil in the bellows, its possible you got so much water in your drive from another leak that when the gear oil heated up and expanded, it forced oil past that seal. I had a leak once and knew it because when I removed the dipstick to check the oil, oil just spurted out and when I removed the drain plug water came out first. You need to drain the drive and check as per the manual. You can have leaks from the prop shaft seals, the drain plug gaskets, the top cover gasket, the shift rod cover gasket, and the water pump shaft seal. Those are the most common.