No Spark

[merit131]

I have a 1989 OMC, Ford V-8, 5.0 L 302, Cobra outdrive. Last year it was fine, now it's driving me nuts. Have no idea why it's not firing at plug. Many new parts, 12V at the coil, but still no spark. New parts coil, Seleniod, starter, distributor, condenser, points, plugs and plug wires, new cables to starter, new ground. New key switch. I'm thinking ESA Module ? It cranks fine, good battery. I've been all over it with my meter. Just don't have any idea of what it could be. Any ideas out there ?

 

[airdvr1227]

Re: No Spark

Could be a ground problem. I had the same thing once and I found a ground wire was disconnected. Sorry I'm not more help.

 

[bruceb58]

Re: No Spark

Have you checked your dwell with a dwell meter? You can crank the engine and see what the dwell is without it running.

Have you pulled the high tension wire to the distributor from the coil and held it close to a ground and cranked the engine?

To see if its the ESA just unplug it. Also, a faulty tach can cause your problems. Disconnect the wire from the negative side of the coil that goes to the tach.

 

[Howard Sterndrive]

Re: No Spark

have you cranked the engine with the distributor cap off to make sure the distributor shaft is turning?

 

[merit131]

Re: No Spark

Thank you I thought of the same thing and I'm still looking, If I can't find it I'm doing to install an electric motor, not so many moving patrs and hook it up to the outdrive. Thanks

 

[merit131]

Re: No Spark

Have not done the dwell thing, I will look into that. But what would that tell me? Yes did the high tension wire to the ground, nothing, no spark. I will also try the ESA, unpluged and the tech wire disconnect thnak you, I'll let you know results.

 

[merit131]

Re: No Spark

Yes I have done that and it is turning. points moving good on cam.

 

[bruceb58]

Re: No Spark

But what would that tell me?

Would tell you if the points are operating properly and that you have good ground at your distributor.

 

[Maclin]

Re: No Spark

Dwell is one of THE tell-all measurements of health for points systems

 

[Silvertip]

Re: No Spark

Dwell is one of THE tell-all measurements of health for points systems

Not necessarily. It tells you dwell angle which is the electronic method of measuring point gap. It has nothing to do with the strength or health of the ignition circuit other than the points are opening and closing for the proper duration and that current is flowing through them.

 

[Silvertip]

Re: No Spark

You mentioned the points are moving good on the cam! Did you at least use a feeler gauge to set the gap on the high spot on the cam lobe? If not you have no idea what the dwell actually is. Even a match book cover will get you close enough to make the engine run. But minimum is a feeler gauge and ideally use of a dwell meter is in order. Once you have it running, you also need to check and adjust timing. Timing doesn't change dwell but dwell does affect timing. You've thrown lots of part at the engine with zero results so it's time to do diagnostic testing instead. The engine ran before so something you did or something a critter did during lay-up is causing the issue.

 

[merit131]

Re: No Spark

I have it in the back yard w/ a cover, no critters can get in. The lay up was only maybe two months tops. I'll check that dwell. Yes did gap the points. Well check tomorrow again. Need to get my friend to come by w/ a dwell meter.

 

[Silvertip]

Re: No Spark

Did you "gap" the points with the cam lobe opening the points at the widest point? Is the kill switch lanyard in place if you have one. This is not the same as the neutral start switch. Coils don't generally go bad while sitting around. There is an "open" circuit in the ignition system somewhere. Coil primary and secondary can be checked with an ohm meter or even a test light to see if an "open" exists. It can also verify a short between primary and secondary windings. I'm not positive about the ignition system on this boat but you might check to see if it uses an external ballast resistor. If it does, there is normally an "R" terminal on the solenoid that bypasses that resistor for starting. If that bypass circuit is open the engine won't start. If the coil has an internal resistor then this is moot.

 

[merit131]

Re: No Spark

Well it's running like a top. I would like to thank everyone for your help. This is what I did. I took off the distrubtor cap and rotor, moved the points and condenser. I noticed the wire coming into the distrubtor needed cleaning and the ground post it was attached to. Then I reinstalled all new parts turned the key and it started right up. So I think it was in the ground wire, or condenser, or maybe the points. The old points were a little pitted. Again thank you all very much for your great advise.