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67 OMC sterndrive

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craig

New member
I have a 67 electric shift OM

I have a 67 electric shift OMC sterndrive that slips out of forward gear when under load. Anyone out there know about these units and what could be wrong? I rebuilt the lower gearcase over the winter and it lasted about 20 minutes before the problem started again.
 
The problem with those drives

The problem with those drives is that they were never a dependable unit in the first place. What your problem may be is the shift spring or clutch is probably slipping or the small tab on the end of the spring has broken off. When you assemble the spring/clutch assembly you should locktite the srping set screw in place to keep it tight. Another problem you could encounter is the shift magnet may not be getting full current to it or may be weak. This can happen if the shift wire is corroded internally and not allowing full current through the wire. Another note-This drive does not last long if the prop is allowed to ventilate or come out of the water and then re-enter the water at a high speed(sometimes a moderate speed).
This puts a high strain on that little tab on the spring. Shifting the drive into gear at a very high idle speed will also cause the last problem to occur.
Tom Jefferson
 
" Tom,

Thanks for your resp

" Tom,

Thanks for your response to my posting.
Let me give you some additional info and see what you think.
Last year I paid a shop a huge price to tear down the lower gearcase and inspect it. Decided to buy the manual and have at it myself. The collar around the forward clutch hub spring had self destructed, so I cleaned all the debris out of the case and bearings. The thrust surface of the forward clutch hub had some burrs and damage, so machined it just enough to clean up the damaged edge. The spring looked fine so reused it. I replaced the collar and all the seals and put it back together. Everything feels tight no slop in the drive shaft or prop shaft. The coil wires LOOK OK on the outside, but who knows?
My gut feeling is the coil, but any way to tell for sure? Current draw test under load?
I just want to fix it so I can sell it without throwing a bucket of money at it.

Thanks for your help, Craig "
 
" Also, I never removed the sp

" Also, I never removed the spring from the forward gear; so didn't get the look at the end of it or even check if the set screws were tight. "
 
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