1989 5.8 shift problems

wrench 3

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Re: 1989 5.8 shift problems

You say the cdi esa works when the over travel switch is bypassed. Ergo, the switch is at fault.
 

bruceb58

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Re: 1989 5.8 shift problems

The overstroke switch disables the ESA.

I am actually surprised the overstroke switch is even being used with newer ESAs.

I am a little confused. You say you die going into neutral, you can't shift into neutral unless you turn off the engine and you also say your ESA isn't working. Can you clarify these one more time?

Which distributor do you have and how is the ESA connected to it? That is likely your issue.

Between CDI and the makers of your distributor, one or both of them likely have the recommended way to kook up the ESA.
 

bruceb58

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Re: 1989 5.8 shift problems

The over travel switch is normally closed except when the throttle is open.
The Overstroke switch is OPEN when the drive is fully in gear. Has nothing to do with the throttle at all.
 

talies13

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Re: 1989 5.8 shift problems

I have an aaamarine hei distributor with upgraded plug wires and the cdi esa module that is especially designed for omc engine. It is supposed to be a simple plug and play install. Remove old esa module and install new cdi esa and plug in thre adapter that comes with it into dist. Then hook up tack wires to the gray wire and hook up purple wire to power that is suposed to be it. When I have it hooked up like this I can start boat and it is in neutral no problems going into gear, but go to shift back into neutral an d can't. I have to shut engine off to get it back in neutral. Allso with it all hooked up properly I can only get 2500 rpms at about 35 mph. With it all hooked up I can not make the engine stumble. If I hook it up like a merc I can make the shift interruptstop the engine.
 

bruceb58

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Re: 1989 5.8 shift problems

Go to this thread that has some diagrams.
http://forums.iboats.com/omc-i-o-inboard-engines-outdrives/esa-not-working-501191.html

Where do you have the wire that normally hooks up to the negative side of the coil if you still had a points style ignition?

You have a separate coil still?

How fast can you go with the ESA unplugged? Just need to make sure the ESA is not causing that issue.

How do you set the timing on that distributor? What is your total advance?
 

wrench 3

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Re: 1989 5.8 shift problems

The Overstroke switch is OPEN when the drive is fully in gear. Has nothing to do with the throttle at all.

Sorry if I worded it wrong, but to my understanding, the throttle is starting to open by the time the shift is fully in gear. Therefore, the switch should be closed when the throttle is at idle.
Any way. It still seems to me that he has a problem with the overstroke switch, its adjustment or its wiring.
 

bruceb58

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Re: 1989 5.8 shift problems

As far as I know, all newer ESAs don't even use the overstroke switch and I thought that also included the CDI ones. Would be easy for the OP to just jumper across the overstroke just to be sure.

Throttle doesn't open at all until drive is fully in gear. ESA switches are operated by shift cable only. This is more of a clarification for the OP.

When the interrupt switch is activated, all its doing is grounding the input to the ESA. Might be worth unplugging the ESA from the switch harness and grounding the appropriate input. Also, the ESA has a wire that gets attached to ground. That has to be a solid ground. Any corrosion will cause the ESA not to work.
 

talies13

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Re: 1989 5.8 shift problems

I am going out in the morning and I will double check wiring. And take pics of what I have going on. I must have something wired wrong.
 

wrench 3

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Re: 1989 5.8 shift problems

As far as I know, all newer ESAs don't even use the overstroke switch and I thought that also included the CDI ones. Would be easy for the OP to just jumper across the overstroke just to be sure.

Throttle doesn't open at all until drive is fully in gear. ESA switches are operated by shift cable only. This is more of a clarification for the OP.

I think I'll leave the throttle issue alone for now.
The shifter on the older Cobras would put the drive all the way into gear before the gear shift ran out of travel. This would trip the interrupter. To stop the ESA from activating when it wasn't needed they added the overstroke switch to override the interrupter switch. In the later models they fixed the problem, but the only way you can eliminate the overstroke switch and have it work properly is to upgrade the linkage.
 

bruceb58

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Re: 1989 5.8 shift problems

I think I'll leave the throttle issue alone for now.
The shifter on the older Cobras would put the drive all the way into gear before the gear shift ran out of travel. This would trip the interrupter. To stop the ESA from activating when it wasn't needed they added the overstroke switch to override the interrupter switch. In the later models they fixed the problem, but the only way you can eliminate the overstroke switch and have it work properly is to upgrade the linkage.
No, the only way to eliminate the overstroke switch is to get the ESA with the timer.

The interrupt switch is tripped by the force put on the lower shift cable while it is pulling the dog clutches apart. This actually happens in the very beginning of the shift travel. The switch isn't tripped going into gear or when shifting out of the water because there isn't enough force to move the cam. Its just not the travel of the shifter that trips the switch. It has to have the force on it to move the cam.

In the picture below, the point at the bottom with the arrow pointing at trunion only moves when there is excessive force put on it by the lower shift cable. That moves the cam that hits the shift switch.
7248459164_05c791d92d.jpg
 

wrench 3

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Re: 1989 5.8 shift problems

OK, so lets say I'm learning here. What is the purpose of the overstroke switch?
 

talies13

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Re: 1989 5.8 shift problems

I just got back from the boat I fixed the ESA I went through and rewired everything and scraped to get a better ground. ESA works but I think my cables are slightly off.. When I go to shift it kills the engine instead of stumbling.
 

bruceb58

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Re: 1989 5.8 shift problems

OK, so lets say I'm learning here. What is the purpose of the overstroke switch?
When the drive is fully in gear, there is no need for the ESA to be operating. If you happem to have a sticky cable that is triggering the interrupt switch, this keeps the ESA from operating. Starting in 1990, OMC came out with the new ESA which only allows the ESA to operate for a number of seconds when a trigger occurs. This allows the overstroke switch to be removed. The newer ESA's plug takes the overstroke switch out of the circuit.
 

bruceb58

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Re: 1989 5.8 shift problems

I just got back from the boat I fixed the ESA I went through and rewired everything and scraped to get a better ground. ESA works but I think my cables are slightly off.. When I go to shift it kills the engine instead of stumbling.
The ESA should only be operating going out of gear. If it is operating going into gear, you have a faulty lower shift cable.
 

wrench 3

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Re: 1989 5.8 shift problems

When the drive is fully in gear, there is no need for the ESA to be operating. If you happem to have a sticky cable that is triggering the interrupt switch, this keeps the ESA from operating. Starting in 1990, OMC came out with the new ESA which only allows the ESA to operate for a number of seconds when a trigger occurs. This allows the overstroke switch to be removed. The newer ESA's plug takes the overstroke switch out of the circuit.

Thanks Bruce. I've had trouble getting information on the ESA system.(probably using the wrong manuals) But from the way they're activated and the way they're wired, I thought I had it figured out. Guess I missed a couple of points.
 

talies13

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Re: 1989 5.8 shift problems

Lower shift cable was replaced 6 months ago. It still measures 7 5/8 fromcenter of hole to back of the nut. I wth the esa plugged in I can shift from neutral to forward no problem and some times forward to neutral. But with esa hooked up I can not go from neutral to reverse without it killing the engine.
 

bruceb58

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Re: 1989 5.8 shift problems

Not sure what you mean by "ESA plugged in" and "ESA hooked up". Should be the same thing.

Also, if you are doing the testing on muffs, The ESA should never operate. Something is binding in your lower shift cable. Could be the bellcrank area is gummed up too.

EDIT: I guess I see your issue...going into reverse is killing the engine. You just said it differently when mentioning reverse.
 

bruceb58

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Re: 1989 5.8 shift problems

Who changed your shift cable? Did you use the special tool when setting the bellcrank angle? Do you store your drive in the down position when not in use? Is this boat ever used in salt water?
 

talies13

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Re: 1989 5.8 shift problems

Yes shift cable was installed with special tool. It is in a fresh water slip with drive down. As you said it would shift fine out of the water . Thanks for the help yall maybe I need to have the cable checked again. In the mean time I will just shut it off when I need to reverse.
 

Reinell-BRXL-191

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Re: 1989 5.8 shift problems

You mean, the shift cable was set with special TOOLS - there are 2 - and they both need to be used at the same time - the dimension of 7 5/8th is wrong, it should be 7 9/16th ( not that slop wouldn't change that dimension) The drive has to be off when the cable is set, there will be a bellcrank tool and a cable length tool - they set both ends of the cable properly
 
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