Engine Shuts Down

[David Rusen]

I have a 88 omc with a 305 chevy engine with points in distributor. The motor stays running as long as you hold the key all the way over on the start position, but as soon as I let the key go the engine shuts off. Has anybody heard of this and is it a quick fix? thanks for any help.

 

[Maclin]

Re: Engine Shuts Down

That is usually a ballast resistor or wiring problem going to the positive terminal of the coil. The coil gets a full 12 volts when cranking, then when the key goes from START back to just ON the coil gets power thru the ballast resistance circuit. Something is amiss in that ballast resistance circuit, could be wiring or a failed ballast resistor component, and that is why it starts ok then dies immediately when the key goes back to ON.

I wish I knew more details about your exact engine setup from OMC, and I apologize for the generic-ness of this post. If they use an actual ballast resistor like an older car then that more than likely has failed, or a terminal connection is corroded or broken or a simple loose connection. If it uses a length of resistance wire then that has broken or failed internally, or again could be a loose splice or connection.

 

[flargin]

Re: Engine Shuts Down

there is typically a wire that supplys 12v from the starter to the coil to ensure there is power to start. There is another wire (purple) that comes from the ignition switch that keeps the coil charged when running.

Likely you have a bad ignition switch or something wrong with the purple wire. it could be the wire, the resistor, or something else in the line from the starting switch to the back. It may be a bad coil as well, but not likely.

Take a volt meter and turn on the key and start figuring out where you loose the 12v.

No quick fix, but it will not be hard to fix once you figure out what it is.

 

[David Rusen]

Re: Engine Shuts Down

Your right on with the purple wire. that wire runs all the way from the ing. switch to just before the alternator where it splits and I guess energizes the alt. I have not had time to check things out in detail yet, but I will tonight. I could not locate a resister as of yet but it was getting dark and I was pissed off so I took a break. I want to thank you for your help and any more info. would be welcome.