250CI MerCruiser Question

[wade7575]

I have a 250CI MerCruiser in a 1973 StarCraft,I'm pretty certain that my coil is bad because I'm not getting any spark.

My problem is the person that had this boat before me put a Chrysler ignition coil on it with a ballast resistor.

I want to put it back to the way it should be but I can't figure out what coil I need for sure because I have seen that there are 6 and 12 volt coil's.

From what I understand GM went to a coil design in the 70's that use 12 volt's but run's on 8 volts I think to compensate for voltage drupe.

I that I car coil will work I just need to know what I'm looking for.

 

[Bondo]

I have a 250CI MerCruiser in a 1973 StarCraft,I'm pretty certain that my coil is bad because I'm not getting any spark.

My problem is the person that had this boat before me put a Chrysler ignition coil on it with a ballast resistor.

I want to put it back to the way it should be but I can't figure out what coil I need for sure because I have seen that there are 6 and 12 volt coil's.

From what I understand GM went to a coil design in the 70's that use 12 volt's but run's on 8 volts I think to compensate for voltage drupe.

I that I car coil will work I just need to know what I'm looking for.

Ayuh,..... The points fires the coil,...... have you serviced the points,..??

 

[wade7575]

The points are new and set correctly,I just need a new coil.

The motor fired before and the coil wasn't changed but I know nothing about the coil and I know it's really old so I want it changed anyway.

If someone knows the correct coil can you please let me know which one to buy,I also need one that use's a resistor wire from what the manual say's but there is no part number.

Also can someone show me what the resistor looks like as well.

 

[matt167]

Chrysler coil and a ballast resistor or a GM coil and a resistor wire does the same thing. If you have 6-9v at the points while running than your golden. Since Chrysler ballast resistors are somewhat known to fail. Check the resistor for voltage and see what you got.

 

[kenny nunez]

Try with a test light or volt meter connected to the + of the coil and spin the engine, there should be full battery voltage in cranking mode only at this point. Also on the distributor side of the coil disconnect the wires and just reconnect the wire that goes to the distributor. If the engine starts look at the shift interrupt switch on the transom and the related wires for grounding or the switch stuck in the closed position, this will indicate a lower shift cable problem.