GM Omc stalls in reverse

[b0mbtrack]

GM OMC 4.3L V-6 carbed. 1988. Cobra drive(not the one where the shift cable goes through the drive but the one where a shift lever is pushed up and down at the boat side of the drive.)

The boats runs fine in fwd but when I put it in reverse and give it gas the engine stalls.

 

[havasuboatman]

Re: GM Omc stalls in reverse

Does it die when it goes into reverse?
Or does it die after it is already in reverse, then you give it throttle?

As it goes into reverse: shift cable adjustment

As you apply throttle after reverse is engaged: Shift cable adjustment or bad shift cable

 

[b0mbtrack]

Re: GM Omc stalls in reverse

It dies after it is already in reverse and I give it gas, so I'll just replace both cable and be done with it. thanks

 

[havasuboatman]

Re: GM Omc stalls in reverse

The cable you need to replace is the one that goes from the top of the engine down to the outdrive, Not the ones that got up to the shift/throttle controller.

 

[King P.V.]

Re: GM Omc stalls in reverse

WTF r u guys talking about????? The cables, no matter which ones you are talking about, have NUTHING to do with the engine "stalling" while going into or after you're in gear......
The shift module should only "scatter" the ignition and not kill the engine. The carb and/or accelerator pump could cause the engine to stall when throttling up, as an example! The shift cables will not cause the engine to die. !!!!!!

 

[longstand]

Re: GM Omc stalls in reverse

WTF r u guys talking about????? The cables, no matter which ones you are talking about, have NUTHING to do with the engine "stalling" while going into or after you're in gear......
The shift module should only "scatter" the ignition and not kill the engine. The carb and/or accelerator pump could cause the engine to stall when throttling up, as an example! The shift cables will not cause the engine to die. !!!!!!

LOL.. Iam no expert. but i Aggry with King P.V. like if i have problem with my Tranny. it will not just stop the engine.. it just keep spinning..LOL

 

[bruceb58]

Re: GM Omc stalls in reverse

LOL.. Iam no expert.

Yep...you are right about that!

 

[bruceb58]

Re: GM Omc stalls in reverse

So lets be clear on this, you shift into reverse and it will run perfectly forever as long as you don't give it any throttle?

 

[bruceb58]

Re: GM Omc stalls in reverse

The shift cables will not cause the engine to die. !!!!!!

They will if the cables are worn/stiff and hold the ESA in the engaged position.

 

[b0mbtrack]

Re: GM Omc stalls in reverse

WTF r u guys talking about????? The cables, no matter which ones you are talking about, have NUTHING to do with the engine "stalling" while going into or after you're in gear......
The shift module should only "scatter" the ignition and not kill the engine. The carb and/or accelerator pump could cause the engine to stall when throttling up, as an example! The shift cables will not cause the engine to die. !!!!!!

No reaon to be a ****, this is why this board is here. Anyway, to clear things up, the engine will stay running in reverse fine untill I give it throttle then the engine stalls. When I run the engine in fwd it runs fine no matter what.

 

[bruceb58]

Re: GM Omc stalls in reverse

Don't you just love it when someone comes on and says this stuff and they are the ones that don't know what they are talking about!

Just for fun, disengage your ESA the next time you are out(you can just unplug it). If that clears it up, you either have to readjust the ESA micro switches or your shift cable is sticking which is holding the ESA engaged.

Just be aware that it may be almost impossible to get it out of gear with the ESA removed and you will have to turn the motor off to shift out of gear. Do this away from the dock.

If you do have this problem, it may do the same thing in your driveway so you can try it there first. The ESA should never normally activate when you are not in water. The ESA should normally only activate coming OUT of gear when there is more force on the cable when trying to disengage the dogs. When you have a bad cable, it will engage the ESA when any movement is done.

 

[b0mbtrack]

Re: GM Omc stalls in reverse

Don't you just love it when someone comes on and says this stuff and they are the ones that don't know what they are talking about!

Just for fun, disengage your ESA the next time you are out(you can just unplug it). If that clears it up, you either have to readjust the ESA micro switches or your shift cable is sticking which is holding the ESA engaged.

Just be aware that it may be almost impossible to get it out of gear with the ESA removed and you will have to turn the motor off to shift out of gear. Do this away from the dock.

If you do have this problem, it may do the same thing in your driveway so you can try it there first. The ESA should never normally activate when you are not in water. The ESA should normally only activate coming OUT of gear when there is more force on the cable when trying to disengage the dogs. When you have a bad cable, it will engage the ESA when any movement is done.

Great thanks for the advice, i'll end up doing this all in the spring though before it goes in the water as I just hauled it and winterized it. Thanks again.

 

[King P.V.]

Re: GM Omc stalls in reverse

Amazing what we have to do to get your attention. I will refrain from calling you any names other to say some of you don't know WTF you are doing by suggesting the shift cable on a OMC Cobra is causing the engine to stall!! AND that the first poster should change it!!! Go ahead, spend your money on advice that's WRONG!!
This is not a Mercruiser!! A Mercruiser will stall/kill the ignition if the cable binds (or more properly, If the intrupter switch is activated for too long a duration., for whatever reason. ) A Cobra shift module (and it's associated interupter switches) should scatter the ignition (make it loap along) but not kill it. Most noticable when coming out of either gear. But almost inperceavable when on the flusher.
OK. so here me now. You could have a bad shift module. It could kill the engine, but it's not designed to...... it should just scatter the firing order only, not kill!! Got it? The shift cable could be bad, it could.. BUT no way will the cable cause the module to kill the engine. And here's why... When you push or pull on the cables back at the brackets at the engine, there is a "V-block" , yes, that's what it's call'd, that moves either way, and activates the interrupter switch. When there is no tension, either way, even if you stop 1/2 way into or out of gear, the V-block will self-center and not activate the switches (which engage the module, which scatters the ignition, which allows you to come out of gear.......... How is this so?? you ask? the v-block has a fairly strong spring, more like a wire actually, semi-wrapped around the v-block. It will allow the v-block to return to center when there is no tension on the shift system, as in... I'm fully in gear or fully out of gear. I am assuming that proper shift cable sdjustments have been done correctly, of course! So, one last time. The module could be bad, killing the engine. The cable could be bad causing the bad module to kill the engine. But, the cable will not cause a good operating module to kill the engine. Again, perhaps the accellerator pump in the carb is weak.......So, if you think I don;t know what the fudge I'm talking about, then go buy a new cable, install it and we'll wait till you come back on this board and ask why your Cobra with the new cable stalls when throttled up, again!! Perhaps Bruce will have a correct answer by then! Have a good day!!

 

[a70eliminator]

Re: GM Omc stalls in reverse

Bruce I don't believe the micro-switch itself is adjustable , it has a fixed position just like the overstroke switch. I agree if cable is out of ajustment and or sticking like you say and the ESA does not return it definately could cause the engine to stall.
King PV I get what your saying about scattering the ignition, but only momentaily while the shift happens 3/10th of a second, but if the is ESA is held for a prolonged duration (sticking cable) the cylinders will load up and cause problems with stalling.

 

[b0mbtrack]

Re: GM Omc stalls in reverse

Amazing what we have to do to get your attention. I will refrain from calling you any names other to say some of you don't know WTF you are doing by suggesting the shift cable on a OMC Cobra is causing the engine to stall!! AND that the first poster should change it!!! Go ahead, spend your money on advice that's WRONG!!
This is not a Mercruiser!! A Mercruiser will stall/kill the ignition if the cable binds (or more properly, If the intrupter switch is activated for too long a duration., for whatever reason. ) A Cobra shift module (and it's associated interupter switches) should scatter the ignition (make it loap along) but not kill it. Most noticable when coming out of either gear. But almost inperceavable when on the flusher.
OK. so here me now. You could have a bad shift module. It could kill the engine, but it's not designed to...... it should just scatter the firing order only, not kill!! Got it? The shift cable could be bad, it could.. BUT no way will the cable cause the module to kill the engine. And here's why... When you push or pull on the cables back at the brackets at the engine, there is a "V-block" , yes, that's what it's call'd, that moves either way, and activates the interrupter switch. When there is no tension, either way, even if you stop 1/2 way into or out of gear, the V-block will self-center and not activate the switches (which engage the module, which scatters the ignition, which allows you to come out of gear.......... How is this so?? you ask? the v-block has a fairly strong spring, more like a wire actually, semi-wrapped around the v-block. It will allow the v-block to return to center when there is no tension on the shift system, as in... I'm fully in gear or fully out of gear. I am assuming that proper shift cable sdjustments have been done correctly, of course! So, one last time. The module could be bad, killing the engine. The cable could be bad causing the bad module to kill the engine. But, the cable will not cause a good operating module to kill the engine. Again, perhaps the accellerator pump in the carb is weak.......So, if you think I don;t know what the fudge I'm talking about, then go buy a new cable, install it and we'll wait till you come back on this board and ask why your Cobra with the new cable stalls when throttled up, again!! Perhaps Bruce will have a correct answer by then! Have a good day!!

Not only are you a **** but you also don't know how to spell.

 

[Lone Duck]

Re: GM Omc stalls in reverse

O.K. Boys settle down! It's going to be a loooonnnggg winter.

 

[bruceb58]

Re: GM Omc stalls in reverse

When there is no tension, either way, even if you stop 1/2 way into or out of gear, the V-block will self-center and not activate the switches

Of course the problem is when the shift cable goes bad and the cable can't go back to a relaxed tension, it holds the interrupt switch in its engaged state.

The ESA stumbles the engine and usually will not cause the engine to die when it is not in gear or coming out of gear. The problem is when the boat is IN gear and the ESA is operating let alone trying at add fuel to an engine where the ESA is operating.

 

[King P.V.]

Re: GM Omc stalls in reverse

....... Look, you are relating two, or more different things. I've had shift "intrupter" modules, kill an engine. That would mean the module has failed. It needs to be replaced. A correctly operating module will not/should not kill the engine. If the engine is in need of a major tune-up, then,,,,, it needs a major tune-up. But a correctly operating module, when activated by the intruper switches should not kill the engine. The cable may be engaging the switches too long, but the engine should just "stumble", that's all. The cable is just the item that engages the switches, which engages the module. The engine should run rough, firing order is unballanced, the engine should not die! BTW, all modules were superceded years ago to alter the cycle of ignition scattering and further helping the "get out of gear' senario. Also, those new modules would not engage above 1200 rpms due to some control boxes providing further travle after the unit is in gear as you throttle up.... Ya, I cna't spell as good as some!! So what?? Hey, bomb..You may remember a line from a song....... "you're funny too"! Any ideas which song??

 

[bonzoscott]

Re: GM Omc stalls in reverse

My boat has almost the same problem except it doesn't stall. It just keeps "scattering" ignition. I'm not too familiar with the part/module, but I get the theory. I can't back it off the trailer. I always have to back it deep. It's been like that since 2nd season and I bought it new (1990). It was under warranty and cables were replaced. That fixed it until next season. Is it a matter of just an adjustment for the module or the cables again?

 

[bruceb58]

Re: GM Omc stalls in reverse

You should start a new thread.

If you last replaced your lower shift cable in 1990 and it lasted this long, you are doing pretty well. My Cobra's shift cables lasted only a few years at a time but I used my boat in saltwater so that may be the difference.