OMC Cobra Outdrive Shift Problems
- Thread starter mikev324
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tugboat kevin
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yes very simple just replace the drive package with merc or volvo and your problem is solved
Read this over and over until you understand the procedures. It's slightly difficult to understand but it will make sense the more you read it.
http://www.hastings.org/~stuart/cobra/
Doug
http://www.hastings.org/~stuart/cobra/
Doug
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To get a Cobra to shift, several things need to be right:
1) The engine idle needs to be consistantly low. If the carb is getting old, the idle can creep up when the engine gets hot. The Cobra wont shift.
2) The control and lower shift cables need to be in top shape, or the Cobra wont shift.
3) The micro switches that control the ESA tend to get coroded over the winter. Check there operation. Switch the one with the roller wheel and the engine should stumble. Check the the forked arm is lubricated up well.
4) Check to see of the drive has water in it. No need to be fixing everything if the drive is full of water.
5) I will disconnect the helm shift cable at the engine, then shift the drive by hand, watching that the ESA switches and lower cable are working well. I do this while running the engine on the trailer. You can work out the bugs, then re attach the helm shift cable.
1) The engine idle needs to be consistantly low. If the carb is getting old, the idle can creep up when the engine gets hot. The Cobra wont shift.
2) The control and lower shift cables need to be in top shape, or the Cobra wont shift.
3) The micro switches that control the ESA tend to get coroded over the winter. Check there operation. Switch the one with the roller wheel and the engine should stumble. Check the the forked arm is lubricated up well.
4) Check to see of the drive has water in it. No need to be fixing everything if the drive is full of water.
5) I will disconnect the helm shift cable at the engine, then shift the drive by hand, watching that the ESA switches and lower cable are working well. I do this while running the engine on the trailer. You can work out the bugs, then re attach the helm shift cable.
Boy! I always thought OMC was a bunch morons for using the ball drive. Didn't know that they didn't even know how their shift system worked. No wonder they went out of business.
Anyway, the OMC dog clutch/shift system is the same design as Merc. Craig has the right procedure to check it.
Oh yeah, you probably have a lower shift cable that needs replacing due to wear or corrosion. Check by disconnecting lower cable and shift by hand. Should shift smooth but you still may not be able to feel the interference.
Anyway, the OMC dog clutch/shift system is the same design as Merc. Craig has the right procedure to check it.
Oh yeah, you probably have a lower shift cable that needs replacing due to wear or corrosion. Check by disconnecting lower cable and shift by hand. Should shift smooth but you still may not be able to feel the interference.
I have an 88 OMC Cobra drive and wouldn't trade it for a merc to save my life. Its been shifting like a volvo for 7 years now.
Mike, you need to do what that web page Doug gave you says, or give it to a mechanic. Years ago there was a recall that changed the cable and possibly a few other things (I can't remember), that solved the Cobra shifting problems. If you have the recall then I do not think the cable will be black, I think it is red or orange. I'll check for you this weekend and let you know for sure. Once you do the recall and have it adjusted properly you will have a wonderfully smooth drive system.
When I bought my boat in 2000, the previous owner had just rebuilt the drive. I had figured that is why he was selling and I knew he didn't have the recall done. So when I took possession, I got the recall done. Its been reliable and smooth ever since.
Your other option might be to replace the Cobra drive with a Volvo SX drive. I hear there is a way to mate this new drive with the old OMC systems.
Shel
Mike, you need to do what that web page Doug gave you says, or give it to a mechanic. Years ago there was a recall that changed the cable and possibly a few other things (I can't remember), that solved the Cobra shifting problems. If you have the recall then I do not think the cable will be black, I think it is red or orange. I'll check for you this weekend and let you know for sure. Once you do the recall and have it adjusted properly you will have a wonderfully smooth drive system.
When I bought my boat in 2000, the previous owner had just rebuilt the drive. I had figured that is why he was selling and I knew he didn't have the recall done. So when I took possession, I got the recall done. Its been reliable and smooth ever since.
Your other option might be to replace the Cobra drive with a Volvo SX drive. I hear there is a way to mate this new drive with the old OMC systems.
Shel
If the recall was done, the cable is definitely red. Don't assume that just because the recall was done that your problem is not the cable. Mine had been previously done but the cable was indeed bad again. The shift cable should have 2.5 lbs of drag when connected to the bell crank at the drive end (outdrive off) but disconnected from the carb side. The bell crank needs to be at exactly 90 degrees. Make sure to grease the bell crank bushing and shaft before reinstalling. If the 2.5 lbs can not be achieved, loosen the retainer on the cable and push the bell crank slightly into the housing, then tighten the retainer. Retest. If the bell crank cavity was full of water/crap/etc, your outdrive seal was leaking and your shift cable should be replaced.
When I had an OMC drive my lower shift cable was the major cause of my troubles. Make sure it is routed cleanly before it exits the transom. Make sure your idle is around 600 rpm when not in gear. If it can't idle that low, check your timing and carb settings. If your ESA switches don't work when activated by hand, your ESA box is probably shot (mine was as well). Ebasicpower had the best price on ESA boxes last time I checked.
Doug
Edit: Where do you live Mike? Anywhere close to Philadelphia, PA? I could give you a hand if you are close by.
When I had an OMC drive my lower shift cable was the major cause of my troubles. Make sure it is routed cleanly before it exits the transom. Make sure your idle is around 600 rpm when not in gear. If it can't idle that low, check your timing and carb settings. If your ESA switches don't work when activated by hand, your ESA box is probably shot (mine was as well). Ebasicpower had the best price on ESA boxes last time I checked.
Doug
Edit: Where do you live Mike? Anywhere close to Philadelphia, PA? I could give you a hand if you are close by.
Thanks Doug, unfortunately I live in Long Island NY...not exactly next door!!
My motor is a new Volvo Penta 5.7 GXI...I'm going to go down to the boat tonight and take a look and see whats going on...I'll take a few pictures and send them to you to see if it helps out at all.
Stay tuned.
My motor is a new Volvo Penta 5.7 GXI...I'm going to go down to the boat tonight and take a look and see whats going on...I'll take a few pictures and send them to you to see if it helps out at all.
Stay tuned.