89 OMC Cobra - No Forward or Reverse

[Camaro-95]

If it matters engine is in a 1989 Four Winns hull
2.3L Inline
OMC Cobra Stern Drive

Boat will not go forwards or reverse
However, when I shift into forward gear or reverse gear the engine will bog down for a second which tells me it is shifting properly.
It will sometimes propel for a short second or two accompanied by loud screeching noise that is mainly heard right after the engine is where it is loudest from what I have been able to tell.

Someone with some knowledge please shed some light on this. If there is any information anyone needs I will be happy to answer. Thanks

 

[Howard Sterndrive]

Re: 89 OMC Cobra - No Forward or Reverse

sounds like the drive coupler splines on the rear of the engine crankshaft have stripped. This is usually caused by a lack of grease in the splines, or engine misalignment. You might be able to feel around back there and find some shards of aluminum and/or rubber. Or pull the outdrive off and look in with a light.

Order an alignment bar when you get the coupler.

 

[Camaro-95]

Re: 89 OMC Cobra - No Forward or Reverse

The loud noise is present when the propeller is turning, and no noise when the propeller isn't turning. Would that drive coupler possibly cause that sort of symptom?

 

[Howard Sterndrive]

Re: 89 OMC Cobra - No Forward or Reverse

the propeller is intermittently turning in gear? I'm not following. I don't get how the propeller is turning but the boat has no F or R.

 

[Camaro-95]

Re: 89 OMC Cobra - No Forward or Reverse

In neutral it acts normal. No prop spin. In F or R it doesn't spin either except when that loud noise is happening but once the noise stops the prop stops.

 

[superbenk]

Re: 89 OMC Cobra - No Forward or Reverse

Spun prop hub maybe? Sounds deeper in though like was suggested with the coupler.

 

[Howard Sterndrive]

Re: 89 OMC Cobra - No Forward or Reverse

In F or R it doesn't spin ....... once the noise stops the prop stops.

I'm still at a loss as to how a prop that was never spinning, stops spinning....

but yeah, sounds like the coupler went

 

[Camaro-95]

Re: 89 OMC Cobra - No Forward or Reverse

Sorry, bad explanation on my part. With engine running, prop does not spin in any gear (except) when loud noise is present. With the noise present the prop will spin BUT once the noise stops, the prop stops

 

[projo198]

Re: 89 OMC Cobra - No Forward or Reverse

I would pull your lower and take a look at the splines. It isn't too hard.

 

[HDSHAF]

Re: 89 OMC Cobra - No Forward or Reverse

Your prop will still spin when your coupler goes out. There is still enough tension on the rubber insert of the coupler to turn the shaft, which in-turn turns the prop. The prop will turn, but only under low rpm. If you smell burnt rubber or see rubber or metal pieces, check the coupler.

 

[bruceb58]

Re: 89 OMC Cobra - No Forward or Reverse

If your coupler was bad enough that it wouldn't spin the prop at all, you would be over heating