3.7 liter Mercruiser coil and choke wires getting very HOT

I have a 1987 mercruiser that the coil wires and choke wires are getting very very hot. This happens almost when you turn the key switch to the on position. I have disconected the wires and turned the key switch on with the same results. Does anyone have any idea what the problem could be?

Re: 3.7 liter Mercruiser coil and choke wires getting very HOT

willymb24 said:

I have a 1987 mercruiser that the coil wires and choke wires are getting very very hot. This happens almost when you turn the key switch to the on position. I have disconected the wires and turned the key switch on with the same results. Does anyone have any idea what the problem could be?

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Welcome to iboats.....
Disconneced the wires from where?......
Anyway, you have a short somewhere, you need to get out the multimeter, test the ignition switch & the wires.....

Re: 3.7 liter Mercruiser coil and choke wires getting very HOT

I disconnected the wires from the choke and coil then turned the key switch on and within seconds the wires were very hot. I have read about the resistance wire do you think that could be a possibility or should I be looking for a short? Thanks

Re: 3.7 liter Mercruiser coil and choke wires getting very HOT

You should be looking for a short. Heated wire means + wire is going -.

Re: 3.7 liter Mercruiser coil and choke wires getting very HOT

Ok thanks so far for the help. So i followed the wire from the coil and it only goes to the carburator. So actually only one wire is getting hot. I cut the wire from the coil to the carburator, turned the key to the on position and I am not having a problem with any wires getting hot. I started it in the driveway and it started right up with no hot wires. I don't want to put the boat in the water yet because I do not know what this wire does. By cutting it it seems to have fixed the problem. Is this the reistor wire? If so do I need it and how would i figure out why it is shorting out or getting hot?

Re: 3.7 liter Mercruiser coil and choke wires getting very HOT

Your wring is screwed up. If the wiring is correct (with the resistance wire cut) your engine should start but would die as soon as you released the key. Somehow you are backfeeding current through the resister wire to the choke whenever the ignition switch is on. Check the other wire on the + side of the coil. Where does it go? If it goes to the starter that is wrong, it should go to a terminal on the slave solenoid. Let us know, and we can try to walk you through the correct wiring steps. Right now you are getting full battery voltage to the coil, which is too much while running. The coil should get its current through the resistance wire while running. Good luck.