OMC outdrive off, oil in bellows

1mtd

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1993 omc cobra 4.3L<br /><br />1)There is maybe 1 or 2 teaspoons of oil in the u-joint bellows- enough to fill about 3 ribs in the bellows. The boat, new to me, had not been serviced in 2 seasons. Outdrive held 15 in. hg for over an hour, but gauge on my tester does not read pressure. Should I get a pressure guage and check the driveshaft seal or is this amount of oil small enough not to worry about until next season?<br /><br />2)Looking through the gimble bearing I can see rust on the back of the motor. Is this normal? Should I spray something in there?<br /><br />Thanks for your help.
 

Don S

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Re: OMC outdrive off, oil in bellows

When you do your pressure test (and vacuum test for that matter) you need to do it with the outdrive drained.<br />With only that minimal amount, I wouldn't worry about it yet. It may have been overfilled, and when it got warm from running it pushed some out into the bellows.<br />Make sure the gear lube full, but not over the full mark on the dipstick and check it after each run. It may not leak till the gear lube is warm and the shaft is spinning. If the level starts to drop, then a reseal of the input shaft is in order
 

1mtd

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Re: OMC outdrive off, oil in bellows

Thanks for the advice, Don. I'll put the drive back on and keep my eye on the oil level.<br /><br />Any thoughts on the rust visible at the back of the motor?
 

P.V.

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Re: OMC outdrive off, oil in bellows

Your u-joint seal and stub-shaft is bad! Waiting for it to get worse is like waiting for cancer to spread from your spleen to something you really need ... like a lung!!! Fix it now, or die later!!
 

Don S

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Re: OMC outdrive off, oil in bellows

Relax PV, as I said, the drive being overfilled can cause the gear lube to leak a little, plus he only had a couple of teaspoon full of oil, not a bellows full. If he does the pressure and vacuume tests and it checks out and he keeps an eye on the gear lube level, it ain't gonna be no deadly spreading cancer waiting to kill his drive.
 

1mtd

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Re: OMC outdrive off, oil in bellows

I guess I should drain the drive again and do a pressure test. Other than running low on oil, are there any other dangers with a leaky seal?
 

KaGee

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Re: OMC outdrive off, oil in bellows

Originally posted by 1mtd:<br /> I guess I should drain the drive again and do a pressure test. Other than running low on oil, are there any other dangers with a leaky seal?
If you have a seal beginning to leak, it will only get worse. What can it lead to? First off, an oily mess and possible discharge of gear oil into the environment. Secondly, a possibility that you could burn up the upper bearings or gears do to oil starvation. COBRAS have a history of that due to improper filling technique. The same can happen if you begin to lose fluid in the upper.<br /><br />About the rust thing... if it bothers you... (it would me) brush it off and paint. Rust is gonna happen no matter what.
 

P.V.

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Re: OMC outdrive off, oil in bellows

I am relax'd. Unlike later MerCruisers, OMC Cobras did not have an oil alert monitor/horn/alarm to tell you that your oil is low, possibly/probably saving your OD and your family from certin DOOM!!!!! When ever we remove an OD and find oil in the bellows, it's a reseal job and probably a stub shaft also, IF the customer wants too! If he doesn't, then the workorder specificly says he refused, his money to do with as he feels to do so!!! . (You'll almost always see the grove that the seal has made into the shaft) We don't do it to cover our A$$s, (OK, perhaps we do!) but to keep the customer from having problems later and have him back on our doorstep pointing his finger/fingers at us!! Remember, a happy customer is a..... happy customer!! I don't know how you or I can judge how much leakage (or non-leakage) is "acceptable" or the fact that when pressure tested staticly, heat and expansion does or doesn't come into play, OR, PERHAPS, someone MAYBE overfill'd the OD!! Did they put 2 ozs too much or did they put 12 ozs too much??? I don't know how much IS acceptable?? But I don't trust a pressure check to tell me that it won't leak again (when oil IS found in the bellows) 1/2 hour later while running down the waterway!! Anyway,it seems like I've gone on too long. I agree that he SHOULD check via pressure/vacuum tests, but I think it could pass and still be "bad". Most shops would leave it up to the customer if he wants to spend the dollars, but encourage him to do the re-seal, just to keep him happy, and safe!! I stand by my previous post above!!!
 

1mtd

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Re: OMC outdrive off, oil in bellows

Guys, I had a chance to pressure test the drive tonight. It held 16 psi for 20 minutes. The guage didn't budge. I put the drive in gear and spun the u-joint shaft for a couple minutes. No change in pressure. The previous vacuum test was fine also.<br /><br />Despite the fact that the seller insisted he had it serviced just before I bought it last june, his records show that the last service was in June 2003. So sometime in the year before I bought it it may have been overfilled. The oil in the bellows was very clean. The oil I drained from the outdrive was black. I bought the boat in sacramento where summer temps can reach 110, although I don't think that should make a difference.<br /><br />I'm all for an ounce of prevention, however I hate spending money on things that aren't broken. What do you think if I clean the bellows well, put the drive back on and run the boat a time or two(checking oil in between), then pull the drive and check the bellows again?
 

Don S

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Re: OMC outdrive off, oil in bellows

I'm all for an ounce of prevention, however I hate spending money on things that aren't broken. What do you think if I clean the bellows well, put the drive back on and run the boat a time or two(checking oil in between), then pull the drive and check the bellows again?
That's what I would do.
 

1mtd

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Re: OMC outdrive off, oil in bellows

I got the boat back from the shop today and thought I'd share the findings. The shift shaft seal was bad and the shaft seal at the impeller adapter plate was bad. I didn't think to move the shift shaft while doing the pressure and vacuum tests. The tech said the oil in the bellows was "melted" grease from the U-joints and nothing to worry about. I had them do a complete reseal anyway. cost me $420. fortunately, the gears looked very good. Thanks for all your help.
 
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