Motor stalling while shifting

[Thewiz]

Hello all,


Im new to this forum. I have a 1800 Diva GT with a 5.0 liter motor and an OMC Cobra outdrive. Recently, it started stalling when I put it in gear, then it starts right away, but does it several times. Seems random. Someone told me it could be the Electronic Shift Assist? Where is this located on the motor, and can I diagnose it myself. Again, Im fairly new to boats, so please bear with me. Thanks in advance for any help.


Brian

 

[legoman67]

Re: Motor stalling while shifting

Its very possible that its the electric shift assist, but without a year its hard to help. What year are the engine and drive?

 

[Thewiz]

Re: Motor stalling while shifting

Without getting the serial/model # I can tell you that it is a 1991 Forester, it's really good shape. I did notice 2 microswitches by the cable on the intake. Is this a neutral safety switch? It looks to me like the switch is "made" after it's put in gear.


Brian

 

[legoman67]

Re: Motor stalling while shifting

yes, one will be neutral saftey, and the other will be the electric shift assist. Basically it cuts power to the engine(coil) for a split second, allowing you to shift easier, and without putting as much strain on the gearbox. If it is not setup right it will activate for too long, enough to completely kill the engine.


on my dads boat, the neutral safety is the one with the longer metal arm, and it rests in a little plate that has 2 humps on either end.... the shift assist is the other one(on the opposite side on that linkage junction thingy/plate) ill see if i can find a pic...

 

[Thewiz]

Re: Motor stalling while shifting

A pic would be great, also is there any way to just unplug/bypass either one to rule out as problems? Like I said, it stalled quite a few times while shifting into gear, and then a couple times while just driving. The problem seems to be something like youre talking about. Does a guy really need these things? This forum is great, it reminds me of the Model T Ford forum I always use. Thanks again!

Brian

 

[legoman67]

Re: Motor stalling while shifting

to temperarily bypass just take an aligator clip from the postive on your coil to the positive on the battery, and another from the negative on the coil, to a good ground point. and run the engine, to kill the engine you will need to pull the clips off...(your key wont kill it..)


the neutral safety is easy to adjust, and i would leave that one, the electric assist i cant really see being a big deal, many boats dont have it at all..

 

[bruceb58]

Re: Motor stalling while shifting

to temperarily bypass just take an aligator clip from the postive on your coil to the positive on the battery, and another from the negative on the coil, to a good ground point. and run the engine, to kill the engine you will need to pull the clips off...(your key wont kill it..)

Wrong...if you ground the ground side of the coil...the engine won't run. Also wrong is supplying a jumper to the positive side of the coil...it already has 12V there.

yes, one will be neutral saftey, and the other will be the electric shift assist.

Also wrong...there are two switches and they both are part of the ESA system. One engages the ESA and one is an overstroke switch. In later ESA modules, the overstroke switch is not needed.

If you want to bypass the ESA to see if that is your problem, disconnect the ESA module's connector. You will probably have a very difficult time getting the boat out of gear but you will be able to see if that is your problem.

Typically, there are two reasons you have the problem you are having. 1)Switches are out of adjustment or 2) Your shift cable is worn and binding. Usually, it is the latter. The ESA is only supposed to operate coming out of gear. That is when the pressure is the greatest. When the cable starts to fail. it happens in both directions. The ESA should not operate when the boat is running on the muffs(assuming a good shift cable) since you don't have the pressure of the water against the propellor putting pressure on the dog gears.

 

[legoman67]

Re: Motor stalling while shifting

Wrong...if you ground the ground side of the coil...the engine won't run. Also wrong is supplying a jumper to the positive side of the coil...it already has 12V there.



Also wrong...there are two switches and they both are part of the ESA system. One engages the ESA and one is an overstroke switch. In later ESA modules, the overstroke switch is not needed.

If you want to bypass the ESA to see if that is your problem, disconnect the ESA module's connector. You will probably have a very difficult time getting the boat out of gear but you will be able to see if that is your problem.

Typically, there are two reasons you have the problem you are having. 1)Switches are out of adjustment or 2) Your shift cable is worn and binding. Usually, it is the latter. The ESA is only supposed to operate coming out of gear. That is when the pressure is the greatest. When the cable starts to fail. it happens in both directions. The ESA should not operate when the boat is running on the muffs(assuming a good shift cable) since you don't have the pressure of the water against the propellor putting pressure on the dog gears.

the coil gets power when you turn the ignition on, and when you turn the ignition off it kills the power, therefor, stopping spark, killing the engine. Anything that would be killing the engine would most likely be between the ignition and the coil.... unless off course other things are bad, but this is the first stages in figuring out what is wrong, if the direct wiring doesnt work, you then move on to deeper issues...

Also, WTF are you talking about, you have to connect the negative to ground or the engine WONT run.... this is a carburated boat correct?

Normally you wouldnt have to ground it because its likely a direct ground as is, but i know afew boats that run the ESA through the ground, and i am not sure which his is, so i was just saying a sure fire way to eliminate the systems.

also, i guess you could call the neutral safety a part of the ESA system.. either way, one of those switches is there to protect you from starting in gear, weather its part of the ESA or not is not really the point..

 

[bruceb58]

Re: Motor stalling while shifting

Neutral safety switches are in the remote control at the helm.

Grounding the negative side of the coil will stop the engine. In fact, that is how the mercruiser shift interrupt system works...it grounds the coil.

 

[bruceb58]

Re: Motor stalling while shifting

Normally you wouldnt have to ground it because its likely a direct ground as is,...

You have no idea how an ignition system works.

You also have no idea how the OMC ESA system works.

 

[legoman67]

Re: Motor stalling while shifting

not all are, for outboards, generally yes, a new boats with electronic shifters yes, but alot of mechanical shifting boats had it down at the shift cable junction thingy...

also, every engine i have looked at, has the - terminal of the coil grounded(usually via the distributor), they all run fine, including the 4 marine v-8 engines i own/ wired myself
here is the part of the wiring diagram from my engine..

 

[bruceb58]

Re: Motor stalling while shifting

also, every engine i have looked at, has the - terminal of the coil grounded, they all run fine, including the 4 marine v-8 engines i own/ wired myself

Wish you were here so we could make a bet! Turn on your engine and put a wire between the negative side of the coil and ground. If the engine turns off you pay me $10 and and if it doesn't I will pay you $10. You can even pay me in Canadian dollars.

Once you do this and figure out how to send me the $10, you will also realize how the ESA system works!

Then read this so you know where the wire goes from the negative side of the coil.

http://www.procarcare.com/icarumba/...icar_resourcecenter_encyclopedia_ignition.asp

 

[legoman67]

Re: Motor stalling while shifting

edit removed

 

[bruceb58]

Re: Motor stalling while shifting

^^ attachment added to above post

Good, now you know that the wire doesn't go to ground but goes to the distributor. It does get grounded...but only when the points close. Its the opening of the points that allows the field to collapse in the coil. This field collapsing coupled with the winding difference between the primary and secondary side of the coil is what produces the high voltage sent to the spark plugs. If the coil is permanently grounded...no field collapse...no spark.

 

[legoman67]

Re: Motor stalling while shifting

hmm, i always figured the connection to the distributor was just a ground point... so forget the second aligator clip, my bad..

 

[bruceb58]

Re: Motor stalling while shifting

hmm, i always figured the connection to the distributor was just a ground point... so forget the second aligator clip, my bad..

yeah...no biggy. Sent you a PM.