Coil

[wrosales]

How hot should a coil be when operating? My boat will crank but after running a bit it will cut off. I have to wait five minutes to get it to crank and then it will die again. It happens at different rpms. I noticed that my coil gets fairly hot. Could this be the problem?

 

[aktrucker]

Re: Coil

I would say it is very likely, but to be sure I would test it.....when it cuts out stop and check spark directly off of the coil, and ALSO make sure you have voltage TO the coil........

Would get better answers/help with engine year/make etc....more info always makes it easier to help diagnose problems.

D

 

[wrosales]

Re: Coil

How do I test spark off the coil? The engine is a 1989 OMC 5.0. Will a coil fail at high temperatures and go back to working when it cools? It did this yesterday and it got to where it would cut off every couple of minutes. I took it back out today to try and diagnose. It ran for about fifteen minutes before it started doing the same thing. Once again it eventually started happening every few minuters. Thanks.

 

[zbnutcase]

Re: Coil

How do I test spark off the coil? The engine is a 1989 OMC 5.0. Will a coil fail at high temperatures and go back to working when it cools? It did this yesterday and it got to where it would cut off every couple of minutes. I took it back out today to try and diagnose. It ran for about fifteen minutes before it started doing the same thing. Once again it eventually started happening every few minuters. Thanks.

Yes, they can die when hot, and work again when cool

 

[aktrucker]

Re: Coil

How do I test spark off the coil?

To test spark directly off the coil do this: Bring a spare spark plug that you know is good, doesn't have to be the same as what's in the engine, just a KNOWN GOOD PLUG. When it dies out, pull the lead (like spark plug wire) that goes from the coil to the distributor cap....remove the lead on the cap side and insert a spark plug into the lead wire. With a spark plug in one end, and the other in the coil, ground the plug and have someone crank the motor....if you get good spark there, your coil is good, if you get week or no spark either your coil is bad, or the power feed to the coil is bad (would bet it will be the coil).

 

[wrosales]

Re: Coil

As far as the temperature on the coil, should you be able to touch it when the engine has been running for a while?

 

[aktrucker]

Re: Coil

As far as the temperature on the coil, should you be able to touch it when the engine has been running for a while?

Ummm....yes, you should be able to touch it. They can get warm, but usually ones I have seen that are "uncomfortably hot to the touch" are pretty well fried.....

 

[wrosales]

Re: Coil

It is definately uncomfortable to touch. I cannot leave my hand on it.

 

[aktrucker]

Re: Coil

I would say the coil is probably shot then...... Not sure what your coil will cost, but I just replaced mine with a Volvo/Penta coil (purchased locally) and I think it was like $40 and I live in a tiny town in Alaska!