OMC Cobra Transom Shift Cable Adjustment Question

[thomasjpierce21]

I recently installed a new shift cable in my 1989 Donzi with an OMC Cobra stern drive. I followed all the instructions in Stuart's fabulous directions that I found on this forum.

In the directions the OMC maintenance guide said that the distance between the end of the cable crimp and the shift cable guide eyelet needs to be 7 5/8" (+/- 1/32").

Does this mean from the end of the crimp on the cable side or from where the threads start with the barrel trunion?

The problem is I can't seem to find the happy medium between the transom shift cable engaging the clutch dog fully and the remote shift cable keeping the ESA switch in the correct position.

The shift pin in the upper housing is set to the correct height, etc and I followed the insructions to a "T"

Ultimately the problem is that when the ESA switch is working correctly the clutch doesn't fully engage leading me to believe the shift cable is the wrong length.

Can anyone shed some light on this?

 

[Gary H NC]

Re: OMC Cobra Transom Shift Cable Adjustment Question

What manual are you using?
The factory service manual has pictures and step by step.
Did you do the bell crank measurement while the drive was off..?( with the correct tool?)
The adjusting is all done with the drive off....Cable measurements and the shift bell crank adjustment.

 

[thomasjpierce21]

Re: OMC Cobra Transom Shift Cable Adjustment Question

Thanks Gary. I'm using the Stuart hastings wensite that includes OMC manual directions with pictures. When the drive was off, I made sure the bell crank was in good shape and not bent like the picture showed (it wasn't) and then lined up the lower tab on the shift cable guide (not worn or tapped wrong) with the gasket surface while making sure the length at the motor was 7 5/8" from the eyelet to the edge of the retainer nut at the end of the brass end. (my last post was just making sure I wasnt suposed to measure from the crimped end on the wire casing itself). I am guessing the directions mean the end of the crimped fitting nearest the threaded end where the cable comes out?

Once I set the cable guide in the transom mount and the 7 5/8 was correct, I screwed the shift cable retainer down the threads to meet with the plastic guide and locked it down with the screw to maintain the set length at the engine.

I didn't have the special bell crank tool but I'm not exactly sure how to use it if I did. It it just to make sure the crank is at 90 degrees when you set the lower tab to the gasket surface?

I'm planning on removing the drive one more time to make sure all measurements are right and I will make a masking tape template like on saw posted in the forum to make sure of that 90 degree setting.

Once all that is correct and the d rive is back on I can make all adjustments from the engine side right? It just seems like the tolerance is so slim on these things that even 1/32" make a difference in engaging the gear completely. Is that the case?

If I can just get the drive side settings right I can figure the rest out based on the instructions in the OMC manual.

Your help is GREATLY appreciated!

 

[Gary H NC]

Re: OMC Cobra Transom Shift Cable Adjustment Question

Thats what i would do...pull the drive and recheck everything.
I wish i would have kept the factory manual from when i had a Cobra.
When i did my cable i remember it had to be exact to shift right..
I am thinking that cable measurement was from the center of the clamp bracket on the cable to the center of the eye on the end.
Not sure though,Its been a long time ago.

I knew i should have kept that manual i payed 70 bucks for...
I gave it to the guy instead...

 

[bruceb58]

Re: OMC Cobra Transom Shift Cable Adjustment Question

The bellcrank angle is critical. If it is not set correctly, the amount of throw will vary between forward and reverse. I always used the OMC tool. See if you can find a marine shop that will loan it to you. What is nice about using it is that it holds it in position while you make the adjustment up at the engine.

 

[thomasjpierce21]

Re: OMC Cobra Transom Shift Cable Adjustment Question

I guess what I am not understanding is when you use the straight edge to even the lower verticle tab on the transom cable guide and the gasket surface, the bell crank will have to be at a certain position because it moves with the cable guide. If the tab and the surface are not even and the bell crank is NOT at 90 degrees what which one do you go with, the tab or the 90 degrees.

I guess this is how Stuart Hastings got away with not using that OMC tool?

 

[Gary H NC]

Re: OMC Cobra Transom Shift Cable Adjustment Question

The bellcrank angle is critical. If it is not set correctly, the amount of throw will vary between forward and reverse. I always used the OMC tool. See if you can find a marine shop that will loan it to you. What is nice about using it is that it holds it in position while you make the adjustment up at the engine.

Agree....that tool makes all the difference.
The OEM manual would be better than Stuarts instructions..I tried both and the OMC manual was dead on.

 

[bruceb58]

Re: OMC Cobra Transom Shift Cable Adjustment Question

Thomas,

I wish I could answer your question with 100% confidence but is has been around 10 years since I last replaced one of those. Since I used the tool, I don't know the relationship of the tab. I would go with the 90 degrees if I had a choice.

After you get all done and have the drive back on, shift the drive between forward and reverse. Note the angle of the shifter when the drive just goes into forward and reverse. They should both occur at the same angle. Better to cheat toward it going into forward earlier than going into reverse if you have to make a choice.

Another thing that that I always felt was important was to eliminate any lost motion so that the control delivers the maximum throw. Make sure the shift cable from the shifter back to the engine is tied into place so that it doesn't flop around. I zip tied mine up to the wiring bundle and sterring cable so it doesn't move. Also, make sure your controller is not worn. My first shifter had tons of slop in it. When I replaced it with a newer controller it made my shifting easier and the adjustment process easier. To see how much play you have, grab the end of the cable and push and pull it to see how much movement there is.

 

[danond]

Re: OMC Cobra Transom Shift Cable Adjustment Question

Stuart Hasting's didn't "Get away" with anything really, the measurement he notes is different than the one noted in the current manual because his "system" is really the one OMC originally recommended, but they went through hell while they replaced gearsets for basically all their customers, so they did everything possible to make sure there was no way to screw up the adjustment process and invented the holding tool, which repositioned the bellcrank, requiring a different measurement at the engine-end of the cable.

The "old" method (using a straight edge) works as long as you use the measurement indicated for this method. Don't mix the two.

 

[michigan boat guy]

I have a 88 omc cobra outdrive when I shift into forward it shuts the motor off. the ESA is tripped. Is that just an cable adjustment problem?

 

[Greg O.]

I did a search on ebay for the bell crank adjustment tool and came up with this. I think I am going to buy one for $50. It should make life easy.

http://www.ebay.com/itm/Shift-Cable...-Cobra-Sterndrive-914017-915271-/301145682016