no spark on 1994 OMC 4.3 (1 Viewer)

[aedavis]

I've got a 1994 Four Winns with a 4.3 that all of a sudden won't start. I ran it at my local lake in February and it ran great, but I can't get it to start now. It is getting fuel to the carb but no spark. It cranks over fine and the kill switch is closed.

This is a 4.3 Chevy engine with a 2 barrel carb. I wanted to verify that the only thing that would cause this is either the coil or the ignition module, right? There is power to the coil but I can't quite figure out how to troubleshoot the module. I've had a hard time finding troubleshooting tips online and I can't get a decent factory manual (OMC's out of business). I've searched on BoatingABC and Iboats and got some info, but not a lot of details on the later model 4.3 like this.

I'd prefer to NOT throw parts at it, mainly because my local boat shop said they almost never see a failure of either the module or the coil on this engine.

Any suggestions?

Thanks,

Allan

 

[fsusteve]

coil failure is rare but not unheard of, did you check all wires and their connections thoroughly? I find it's usually something simple on my boats.

 

[ellington12]

pop off the distributor cap and make sure the distributor spins when you crank the engine.

 

[IggyB]

if it's anything like the 4.3 I had in the 89 Jimmy, the ignition module is a small plastic 3 or 4 pronged plug in piece under the distributor cap.

It went on me 3 times. The truck would crank over forever but would not start. Local parts store tested the module, declared it dead and sold me a new one for 50 bucks. Plugged it in and truck started on first try.

 

[60wagondiesel]

X2 on the module if got a 4.3 in a blazer and i've replaced it twice.... but should get it checked first before throwing in parts you dont really need

 

[aedavis]

Thanks for the responses.

Against my better judgement, I opted to let my local boat store diagnose this. They did and said their checks showed the ignition module had failed. I'm waiting on a replacement module right now.

I hope they're right - summer is here and I want to get on the lake!

I'll post up when I get the boat back.

Allan

 

[aedavis]

FYI - I got my boat back over the weekend. Both the ignition module and the coil failed according to the boat shop. Both were replaced and it's running fine now.

Allan