86 OMC cobra 400 losing oil

[Paul.v]

Hey guys.

 

[sethjon]

Re: 86 OMC cobra 400 losing oil

You need to pull the OD and replace the seals. While in there check to make sure the gears are in good shape, replace the impeller, and I would replace the gimbl gear too.

 

[bruceb58]

Re: 86 OMC cobra 400 losing oil

You need to pull the OD and replace the seals. While in there check to make sure the gears are in good shape, replace the impeller, and I would replace the gimbl gear too.

He doesn't have a gimble bearing.

 

[Howard Sterndrive]

Re: 86 OMC cobra 400 losing oil

He doesn't have a gimble bearing.

86 OMC cobra 400

he's not sure what he has

 

[sethjon]

Re: 86 OMC cobra 400 losing oil

He doesn't have a gimble bearing.

Thanks for the correction. I have an '89 and it has a gimble bearing.

 

[bruceb58]

Re: 86 OMC cobra 400 losing oil

You are right he doesn't know what he has. It can't be both a Cobra and a 400 so he could still have a gimble bearing. Sorry about that Sethjon.

 

[Paul.v]

Re: 86 OMC cobra 400 losing oil

thanks guys

 

[bruceb58]

Re: 86 OMC cobra 400 losing oil

not uncommon to see them used still to describe the smaller cobra vs the larger cobra.

All Cobras are the same size so the 400/800 is never used.

You need to drain all the drive oil and pressure test it. Where are you losing oil?

 

[Paul.v]

Re: 86 OMC cobra 400 losing oil

Thats funny, I could have swore the v8 i have is 15 spline prop shaft & the 4 cyl is 13 spline shaftThanks,
Paul

 

[bruceb58]

Re: 86 OMC cobra 400 losing oil

Yes...drive should be off. Where is the oil getting out?

Yes..splines are different. You are correct about that.

 

[Paul.v]

Re: 86 OMC cobra 400 losing oil

Thanks Bruce, when you asked wher the oil is getting out I thought you meant to look under pressure test. I am not sure where oil is getting out...just a slick on the lake which I cant stand...I lost about a pint in 25 minutes or so!! I will try pressure test as you say, I imagine with a leak that bad it should be easy to isolate/see unless its the seal between the upper & lower.......?

 

[bruceb58]

Re: 86 OMC cobra 400 losing oil

Probably the most likely is the propeller shaft if it is leaking into the water and not the drive shaft bellows. Less likely to leak between upper and lower unless the drive was split and 0-rings were not replaced when reassembled. Also, just for info, you always want to replace the o-rings/gaskets on drain/fill plugs when you drain and refill the drive.

When you refill the drive, do you fill from the middle hole? Filling from the bottom will cause an air pocket to form which may look like you are losing oil once the air pocket releases.

 

[Paul.v]

Re: 86 OMC cobra 400 losing oil

thanks again

 

[bruceb58]

Re: 86 OMC cobra 400 losing oil

No, you fill from the middle hole only until oil reaches the top.

 

[Paul.v]

Re: 86 OMC cobra 400 losing oil

Ok, thanks for the clarification. Thanks,
Paul