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OMC Cobra ESA module

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50kstrafo

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I have a 1986 OMC Cobra. The engine has been replaced with a 2000 4.3l Chevy engine. This engine has a conventional points. The ESA unit on the boat is a model#987567. From what I have found out, I believe this is the wrong ESA unit for this boat. 987567 is an ESA for electronic ignition. Does anybody know which ESA unit would be the correct unit for this type of engine????
 
This is listed for a 1990 4.3l motor from this website.
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SHIFT ASSIST MODULE KIT 18-5890
 
1990 shows a electronic dist. Ether way you can take the esa out and wire it like a merc. The micro that activates the esa.... you just run one wire to the neg side of the dist, and the other wire to a ground and your done.
The over stroke micro you leave alone tie up the wire or remove.

Now when you shift it will stumble the motor just like a merc no need for a esa module.
 
Wow Master Mechanic! are you sure that is a good practice on a cobra? anyone tried it? I cant imagine OMC adding the ESA just to screw with us?? Also Cost is usually cut wherever but not if reliability is affected(hopefully) Have you tried this yourself under load? no extra clunking? I would be careful not to save $100 only to cost a drive later...IMHO
 
Yep tried it and it works. How does a alpha shift ? What stumbles the motor ? Don't forget idle in the water, on a warm motor in gear, you want around 600 to 650 rpm.
 
Pauly,
OMC ESA = Electric Shift Assist.
Merc's SA = Shift Assist.
Either accomplishes basically the same thing by stumbling rpm momentarily during a shift from gear back into neutral due to Dog Clutch resistance while under prop thrust.
The ESA is apparently a bit more effective at doing this, and this is due to the more sensative dog clutch system of the Cobra drive.
Get this wrong, and you can damage the drive.
Google Stuart Hastings OMC and read Stuart's thread on this.

And take MM's suggestion about being IN the Water during the final adjustment. No prop thrust.... no accurate adjustment.

Questions:

  • isn't the ESA upgrade for use with the electronic ignition a plug in module on these?
  • if so.... can't the module be unplugged, and the ESA be reconfigured to the OEM?
  • and just curious....., why are you still using mechanical contacts with this engine?
 
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