omc timing and questions

wnaplay

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Against my objectiins my buddy bought an 85 boat with a 3.0 omc inboard. He approached the boat as a car and decided to do some tuning and now as it way out of time. I spoke with my mechanic in another state and he gave me basic information. The mechanic stated that if their was a plug or dangling wire on the distributer it was a matter of grounding those out (putting in base time) and timing. Without either of those to set the timing you need to put it in base time, set dwell, set ignition speed them time normally. Neither of us know how to do these things. My buddy originally tried to adjust timing 6-8 degrees but everytime he brought idle back down it died. He called me and i made the call to the mechanic who confirmed my opinion that I have no idea. Any suggestionhow to get this back to running condition and please be as specific or explanatory as possible as in do this and then this. I have never messed with dwell or setting ignition speed.
 

MikDee

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If it's a 1985 boat, and the original motor, then no putting it into "base timing" is necessary, just put a conventional inductive timing light on Cyl. #1 spark plug wire (the front one, towards the bow of the boat). Then loosen the Distributor, and move it to suit the specified timing of your motor at normal idle speed. When set, remember to tighten down the Distributor. Enclosed is a basic wiring diagram, the colors may not match yours, but the schematic is right. If you have points, and condenser ignition, the points need to be set first, before the timing.
 

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wnaplay

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This is what they originally did which started the whole mess. Unsure exactly how because I was consulted after it wouldnt stay running and just before the downpour which caused them to give up.
 

wnaplay

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My buddy did say he believed it had an est or esa ignition system if that makes any sense.
 

wnaplay

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Esa ignition. Took it to 2 different boat mechanics but they dont touch omc.
 

bruceb58

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ESA is not an ignition. Its a module that is used on OMC to help you get out of gear.

I am assuming this is a points distributor still? If so, change the points and adjust with a dwell meter followed by setting timing to spec.
 

wnaplay

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How do you set dwell and what do i need? I heard you can set dwell with some multimeters but i have no idea what it is let alone how to set it . Also the mechanic i spoke with first said set dwell then ignition speed(whats this) then time.
 

bruceb58

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He meant set dwell and then ignition timing.

Use a dwell meter like this:
http://www.amazon.com/Tekpower-HP981...ds=dwell+meter
or this:
http://www.amazon.com/Actron-CP7605-...ds=dwell+meter
You adjust the points opening to set the dwell. You start out by setting the air gap with the points on their higheset lobe and then set them accurately with the dwell meter.

Set timing with a timing light:
http://www.amazon.com/INNOVA-3551-In...XTTAD45FJ8RNQD

You can spend a little more and get something that does timing, measures dwell and has an advance function that lets you measure total timing advance more easily:
http://www.amazon.com/INNOVA-5568-Pr...ng+light+dwell
 
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