OMC Cobra 4.3 Troubles Shifting into Reverse

[boatgrunt]

I have a 1990 Citation boat with a OMC Cobra sterndrive powered by a Chevy V6 4.3L engine. I am having troubles shifting into reverse, especially while in the water. When running the motor in my driveway with the muffs, she shifts into reverse with little if no grinding. In the water, not only does it grind into reverse but it knocks, shakes and continues to grind when I increse the throttle. I am having no problems shifting into forward. Do I need the adjustment referred to by the infamous http://www.hastings.org/~stuart/cobra/index.html site or is the problem something different?

 

[vicsponjr]

Re: OMC Cobra 4.3 Troubles Shifting into Reverse

Did you try the esa switch to see if the esa is working? You should be able to push the switch while in neutral and engine rpm's should drop. If this doesn't work, then you have either a bad switch or module. How high are your rpm's? Honestly though, the grinding you describe scares me. Cable may be out of adjustment.<br />I got off easy, with mine it was just the ESA module, got it at go2marine.com for $98, thanks to Ron and others.

 

[boatgrunt]

Re: OMC Cobra 4.3 Troubles Shifting into Reverse

Thanks Victor. I'm reading all that I can (including the manual) and learning as I go, but unfortunately, I don't yet know what an "ESA" is. What/where is it?<br /><br />Thanks

 

[mike11374]

Re: OMC Cobra 4.3 Troubles Shifting into Reverse

I had the same problem with mine but it involved my forward gear. Turned out to be a 10 minute adjustment. Cost me a case of beer to my great mechanic. Let me know how it turns out.

 

[vicsponjr]

Re: OMC Cobra 4.3 Troubles Shifting into Reverse

That's what it sounds like to me, Mike. An adjustment.<br />Electronic shift assist. The ESA consists of two switches and a module. The ESA switch has a roller on it. If its like mine it will be on the starboard side of the engine on the cable mount bracket. There will be wires coming from there leading to overstroke switch and then to the module, module on mine is mounted right on top of the manifold.

 

[boatgrunt]

Re: OMC Cobra 4.3 Troubles Shifting into Reverse

Thanks Victor. I read that the ESA briefly reduces the enginge RPMs to allow the clutch and gears to engage easier. The article said that if you are having trouble shifting OUT of gear, than the ESA is suspect. If you are having trouble shifting into gear, it said to try adjusting the shift linkage. Were you having trouble shifting into gear or out of gear?

 

[vicsponjr]

Re: OMC Cobra 4.3 Troubles Shifting into Reverse

I was having trouble getting out of gear. I guess you need an adjustment...

 

[boatgrunt]

Re: OMC Cobra 4.3 Troubles Shifting into Reverse

...that's what I was afraid of. Thanks for the tip though - now I know what an ESA is.

 

[seahorse5]

Re: OMC Cobra 4.3 Troubles Shifting into Reverse

If there is a problem shifting INTO gear, then it is not an ESA problem, but most likely cable, linkage, or bushings that are corroded, worn, or stiff.<br /><br />Find a QUALIFED Cobra mechanic to look it over. <br /><br />A very common problem is with boats that are used infrequently where corrosion and marine growth restricts the shift rod on the lower gear housing from going fully into gear.

 

[bijou22]

Re: OMC Cobra 4.3 Troubles Shifting into Reverse

I had a similar probelm the other day, and it was also very stiff going forward. Try taking the cover off the sterndrive and put boat into reverse (engine off). Does the gear lever move? if not adjust as neccesary. Its quite easy. hope this helps

 

[boatgrunt]

Re: OMC Cobra 4.3 Troubles Shifting into Reverse

Thanks - I'm going to make the adjustment this fall. I'll post the final verdict when I'm done.

 

[lakelivin]

Re: OMC Cobra 4.3 Troubles Shifting into Reverse

Originally posted by bijou22:<br /> I had a similar probelm the other day, and it was also very stiff going forward. Try taking the cover off the sterndrive and put boat into reverse (engine off). Does the gear lever move? if not adjust as neccesary. Its quite easy. hope this helps

bijou- what do you mean by 'taking the cover off the sterndrive'? Are you talking about a Cobra, & if so, what year? Confused....

 

[Lou C]

Re: OMC Cobra 4.3 Troubles Shifting into Reverse

Aint nothin under a Cobra cover but a water pump, must be talking about a stringer!

 

[lakelivin]

Re: OMC Cobra 4.3 Troubles Shifting into Reverse

Originally posted by Lou C:<br /> Aint nothin under a Cobra cover but a water pump, must be talking about a stringer!

You can also pull the top off where the oil check dipstick goes (4 bolts) & see the upper gear & pinion (I think, never did it myself), but didn't think there was any way to view the shift rod on a cobra without pulling the drive...

 

[bijou22]

Re: OMC Cobra 4.3 Troubles Shifting into Reverse

cobra model is 1996, not sure what you actually call it, but it covers the part where the cable pulls the gear lever. This is where I adjusted it

 

[lakelivin]

Re: OMC Cobra 4.3 Troubles Shifting into Reverse

bijou - I really don't think you have a Cobra. On a cobra the cable doesn't pull the gear lever directly, rather the transom shift cable connects to the following in the pivot housing: a cable shift guide, which connects to a shift lever, which connects to a bellcrank. The bellcrank is what fits into the 'v-notch' on the shift rod in the actual sterndrive unit.<br /><br />Just saw in another thread that OMC used straight mechanical 800 stringers on 1982-1986 boats. Although OMC started using Cobras in '86, wonder if you have a transistion year 800 stringer?

 

[bijou22]

Re: OMC Cobra 4.3 Troubles Shifting into Reverse

maybe I have not explained it properley. I do have a Cobra SX leg and I am talking about the first point of contact the cable has with the drive, which is hidden under the casing accesible from the boat.There are 4 screws holding it down. hope this makes it clearer. Its here that I adjusted mine and solved the problem.

 

[Lou C]

Re: OMC Cobra 4.3 Troubles Shifting into Reverse

The Cobra SX is the joint venture one made with Volvo, that has the shifting in the upper unit. Totally different inside than the original OMC dog clutch model. Original was 86-93. Joint venture Cobra SX/Volvo SX started in 94.

 

[lakelivin]

Re: OMC Cobra 4.3 Troubles Shifting into Reverse

Ah, that 'splains the confusion. Unfortunately, I suspect there might be fewer iBoaters familiar with the SX setup than with the regular Cobra...