Mercruiser 3.0 hot coil

[badboatguy]

I installed a ignitor 1146A and 3ohm flamethrower coil on my 1989 mercruiser 3.0. It will start and run perfectly for an hour or two and then I lose spark and it dies until it cools off. The coil and distributer will be too hot to touch at this time. I installed the coil and ignitor by eliminating the resistance wire and running a wire spliced into the choke. I had originally installed it using the resistance wire for the power source with the same results. I appreciate any help, thanks!

 

[GSPLures]

Possible the coil is bad from the company, did you also change out the spark plugs possible one or more has a lot of internal resistance?


Did you have the issue before the upgrade?

 

[badboatguy]

I had the problem last year as well with the old spark plugs, (acdelco MR43T). The same brand I'm running this year. Hopefully, these work with electronic ignition. I did just change the spark plug wires thinking they might be the problem. I also bought a new coil to eliminate that as a possibility. I'm taking the boat out tomorrow so we'll see how it goes. Thanks!

 

[GSPLures]

I had the problem last year as well with the old spark plugs, (acdelco MR43T). The same brand I'm running this year. Hopefully, these work with electronic ignition. I did just change the spark plug wires thinking they might be the problem. I also bought a new coil to eliminate that as a possibility. I'm taking the boat out tomorrow so we'll see how it goes. Thanks!

I meant plug wires sorry just realized I forgot the wire part

 

[GSPLures]

On the pertronix ignitor if you leave the ignition key in the on position and not started the coil will get hot. I just did it today unfortunately, I wont know if I burned up the pertronix until tomorrow hopefully I didnt

 

[sam am I]

I don't think the problem(over heating) is being caused on the secondary side (plugs, wires etc)think you're chasing ghosts there!.........The heat is probably being created on the primary side of the coil because you've and/or a PO have modified things beyond the stock setup and the coil's primary side current is too high.....

My first question would be do you know if the current(present) coil REQUIRES a external resistor? (aka "ballast resistor" or "resistor wire"). Sounds like it does require one and you need to find the proper value at that, this evidenced by way overheating, "too hot to touch".

Second, does your setup (i'm not a mercruiser guy and too lazy to look it up, maybe someone here that is can chime in, but I'll assume it does) use a solenoid that has a "I" terminal? And if so, are you wiring it properly for said ballast resistance?