Problem engaging gears on OMC 4.3L

[mdamerell]

I have a 1988 17ft Sunbird Corsair with an OMC 4.3L V6 - 175hp, problem is that when I go into gear it crunches and is really hard to get out of gear, on investigation the switch terminal by the throttle cable is not working, and I think is the ESB down on the side of the engine has been diconnected at some stage, as if to bypass the system, there is a purple wire for some reason going from the Distributor to the coil which is not shown in the wiring diagram I have in my engine manual, I have got the rev counter working by connecting the two grey wires to the coil. the wires around the esb unit have been cut. need help, wiring info, part numbers, and instructions, any help greatly appreciated.

 

[KaGee]

Re: Problem engaging gears on OMC 4.3L

Sound symptomatic of an ESA module not working right.<br /><br />You'll have to get a wire diagram from a SELOC or CLYMER's manual to trace back your wiring. You might check your library.

 

[Don S]

Re: Problem engaging gears on OMC 4.3L

Below is the wiring for your engine. You really do need to get a manual if you are going to be working on your engine and drive. Too many things you can miss.<br />Plus, here is a site with some additional OMC information.<br /> OMC Tech Info <br /><br />

 

[mdamerell]

Re: Problem engaging gears on OMC 4.3L

Many thanks for the information, starting the process of elimination. but I am worried that because the engine has been changed from breaker point ignition, that I will still get problems - any thought?

 

[Don S]

Re: Problem engaging gears on OMC 4.3L

Depends on the type electronic ignition installed.<br />Going from points type distributor to the electronic ignition does cause problems with a few of them. One possiblility is to remove the ESA module from the system and hook up the shift interrupt switches like Mercruiser shift interrupt system.

 

[JustMrWill]

Re: Problem engaging gears on OMC 4.3L

I know that if you upgrade to a Pertronix ignition on an OMC you need to make some modifications as outlined <br /><br /> http://www.pertronix.com/tech_support/assets/diodefix.pdf

 

[KaGee]

Re: Problem engaging gears on OMC 4.3L

There are also modded ESA's out there to accomodate the electronic ignitions, in case you don't want to mess soldering and such. I had a link to a place, but sorry, I can't find what I did with it. See my avitar?

 

[KaGee]

Re: Problem engaging gears on OMC 4.3L

Originally posted by 16Pilot:<br /> I have a 1990 that still has the red cable, should I be concerned here?

If it aint broke.... don't fix it.

 

[mdamerell]

Re: Problem engaging gears on OMC 4.3L

Sorry KaGee whats my Avitar?

 

[Don S]

Re: Problem engaging gears on OMC 4.3L

The Avitar is the picture under his name on the left side of the screen.

 

[16Pilot]

Re: Problem engaging gears on OMC 4.3L

I have a 1990 that still has the red cable, should I be concerned here?

 

[mdamerell]

Re: Problem engaging gears on OMC 4.3L

Don S please can you supply any wiring info and technical info for the Mercruiser method of the interupt system<br /><br />Thanks

 

[rodbolt]

Re: Problem engaging gears on OMC 4.3L

hello<br /> tell us what ign system you have now. or desribe what the dist looks like in detail. does it have a dry coil or a oil filled coil. the Delco EST cant use the ESA module. also does your 1988 have an overstroke switch on the same plate as the interuppt switch?<br />I just rewired one on a 1989 bayliner to accept the EST ignition for an indmar 5.7. talk about a enenering work of art. I dont know who but it all together but it took me 11 hours to straighten it out to meet uscg and to actually work.<br /> so try to get us an ign type and we can help.<br /> the ESA module,or lack of, wont affect going into gear. just coming out of any gear.<br /> so you may have inherited multiple problems.

 

[mdamerell]

Re: Problem engaging gears on OMC 4.3L

Thanks Rodbolt, not sure what the dist is, how is it identified, the overstroke switch is on the same plate as the interuppt. can you commnicate via email

 

[KaGee]

Re: Problem engaging gears on OMC 4.3L

I believe that OMC used prestolite on that engine, but I could be wrong. MD...look for a metal tag on the distributor for ID.<br /><br />Rodbolt..<br />I am extremely jealous that you live in Kitty Hawk! One of my favorite areas. The wife's aunt lives about 40 miles north of you in Coinjock off the main highway.

 

[Don S]

Re: Problem engaging gears on OMC 4.3L

Its simple to rewire it like a Mercruiser. From the shift interrupt switch, one of the wires goes to ground, the other wire goes to the (-) Dist. side of the coil. But it's still going to depend on the type of electronic distributor you have.<br />Can you post a picture of it? A picture of the distributor with the cap on and one with it off so we could see the inside would help.

 

[rodbolt]

Re: Problem engaging gears on OMC 4.3L

hello<br /> the prestolite used a module with a purple and black two wire module. its a big silver can in the dist housing. the EST uses a standard looking cap but the portion over the module terminal exit has a big square cut out, does not have mechanical advance and uses a flat plasitc module with a two pin and a 4 or five(depending on the model) connetctors.if you can post a pic of the dist it will be most helpful.<br />to use the cut out switch with most non stock electronic distributors you have to rewire the plugs on the cut out and overstroke switches.

 

[Don S]

Re: Problem engaging gears on OMC 4.3L

Here are a couple of picture that might help.<br /><br />Prestolite distributor<br />

<br /><br />Delco EST Distributor<br />

 

[rodbolt]

Re: Problem engaging gears on OMC 4.3L

dang<br /> I gotta get puter literate like don<br /> I like pictures<br /> makes descriptions make more sense.<br /> thanks Don

 

[mdamerell]

Re: Problem engaging gears on OMC 4.3L

Well I have got it all connected, she starts up and ticks over lovely, when she is eventually warm. when I push the interuppter lever nothing happens, I put a multimeter on the switch and when I operate it manually the meters beeps at me. I have checked the connections and they are fine, so I am thinking there is something wrong with the esa module. How can I test it, looking at the Seloc Manual I discovered that this upgrade to electronic ignition is very similar to a 1991 4.3l I think it is, with no overstroke switch in the wiring, and 5 wires from the ESA module, my distrubutor looks like the prestolite one above,