Effects of bad OMC Cobra Gear Oil Change

[candiaoh]

Last season, I had the local mechanic at my Marina (middle of nowhere) change my gear oil on my 1990 OMC Cobra drive. Not soon after, I launched her for the season, and that very day, I began experience the problem of not being able to shift to neutral, only forward or reverse.

After some research here, I intuitively narrowed the problem to either a shift cable or ESA module as the likely culprit.

I asked this same marine mechanic if I got the parts if he would do the work. He replied he does not work on OMC, only Mercruiser.

I did not think much of the comment until today- reading how OMC gear oil changes are different from Mercruiser.

If he did not do the procedure correctly, and he did not account for the "air bubble", would an underfilled gear case cause the failed shift to neutral? Thankfully, I did not run the boat much at all last summer. From the Marina to my dock, back to the Marina and on the the trailer for the winter.

I am going down this week to check the dipstick and see what the level is in the gear oil.

 

[bruceb58]

Re: Effects of bad OMC Cobra Gear Oil Change

Checking the dipstick will tell you everything you need to know about his oil fill. The shifting is going to be a different issue and won't be the ESA. It is more than likely a worn out lower shift cable. Tilt the drive up and look up from the starboard side of the drive and see what the cable housing looks like as it enters the drive. That is where these fail. Do you keep your drive stored in the down position? Keeping the drive stored down keeps the cable in a more relaxed state and will last much longer than if you keep the drive up.

 

[candiaoh]

Re: Effects of bad OMC Cobra Gear Oil Change

So I guess my theory that maybe the gear box overheated due to lack of fluid and causing shifting issues does not wash?

 

[bruceb58]

Re: Effects of bad OMC Cobra Gear Oil Change

Not really!

When I had my OMC Cobra, I replaced that cable 3 or 4 times. They go out often especially if you use the boat in salt water.

 

[candiaoh]

Re: Effects of bad OMC Cobra Gear Oil Change

I don't run it in Salt Water. I have no idea how old the Shift Cable is, I bought it about two years ago. For all I know, its original.

The nearest OMC mechanic told me about $500 to replace the shift cable, and Lord knows what else he'll tell me once I get it there.

That's why I was hoping it was either the fluid or and ESA issue.

 

[Gary H NC]

Re: Effects of bad OMC Cobra Gear Oil Change

What size motor does it have? The 4.3 and 5.0 models hold 64 ounces of gear lube.
If it was not filled enough it usually wipes the upper gears out in no time.

 

[Gary H NC]

Re: Effects of bad OMC Cobra Gear Oil Change

The shift cable is about 100 bucks.
Get the OEM service manual and in about 2 hours you can change it yourself...

The best money you will ever spend on the boat,
Email the seller with your serial number and tell him Gary in NC sent you.
http://cgi.ebay.com/ebaymotors/1990...00433967761QQptZMotorsQ5fManualsQ5fLiterature

 

[candiaoh]

Re: Effects of bad OMC Cobra Gear Oil Change

4.3...which is why I am glad I ran it from the dock to the Marina and back. It ran all of about 20 minutes last summer after the oil change.

 

[candiaoh]

Re: Effects of bad OMC Cobra Gear Oil Change

I thought you need special tools?

 

[Gary H NC]

Re: Effects of bad OMC Cobra Gear Oil Change

Yep,The 4.3 holds 64 ounces...
I added a link to the above post for the real factory manual.
It has all the adjustment measurements and great pics for changing the cable.Those are critical on the Cobra drives.

 

[Gary H NC]

Re: Effects of bad OMC Cobra Gear Oil Change

I thought you need special tools?

Nope...changed many Cobra shift cables. A small square to set the bell crank at 90 degrees and a measuring tape will do fine.
The manual explains it very well.

 

[bruceb58]

Re: Effects of bad OMC Cobra Gear Oil Change

And an alignment bar to check your alignment. This should really be done yearly. You can pick up an alignment bar on eBay.