48 cub coil

[Mike in Ohio]

Coil gets almost too hot to touch after about 15 minutes running. Quits running after 30 or 35.

Was a mag setup converted to external coil by a previous owner. Mag distributer still on it.

The wire between switch and pos side of coil seems kinda small.,could this be a problem?

6 volt system.

The coil says " for 6 vol without external resistor,
for 12 volt with external resistor "
.
Should the coil or the wire have a resistor on them

Thanks for any help

 

[Bob]

You say it's still a 6 V system, so no ballast resistor is needed.

What is the battery charging voltage... should be around 8.4 Volts for a 6 Volt system.

Other than that, it seems you have a "bad" coil.

 

[Bob]

Also, do you have a way to measure primary igntion current, should be in the 3 to 4 Amp range.

 

[Mike in Ohio]

I will check charge voltage when I get home. Coil is new but it came from tractor supply,only place open on Sunday.

 

[rustyfarmall]

Might be as simple as a defective ignition coil.

 

[Mike in Ohio]

I have a multimeter,where do I measure that?

 

[Mike in Ohio]

Coil is new old, one did the same thing, but I think we damaged it because after a while it didn't have any spark. New coil it started right up, I am thinking something else is causing the coils to heat up, just don't know what yet.

 

[jsfarmall]

I would just put a new coil and possibly
heavier wire. Only 20 bucks. If ya ever
switch to 12v don't fool with a resistor,
just get an internally resisted coil. Not
near enough price difference to worry
about.

 

[Mike in Ohio]

Should the wire from the switch be going into the positive or negative side of the coils on a positive ground system?

Would the wires being being reversed cause it to heat up?

Thanks again for the help.

 

[Bob]

"Should the wire from the switch be going into the positive or negative side of the coils on a positive ground system?"

Positive.


"Would the wires being being reversed cause it to heat up?"

No.

 

[Mike in Ohio]

(quoted from post at 12:35:37 07/28/16) You say it's still a 6 V system, so no ballast resistor is needed.

What is the battery charging voltage... should be around 8.4 Volts for a 6 Volt system.

Other than that, it seems you have a "bad" coil.

Only 6 volts across the battery when running, but the amps across the coil with the neg grounded maxes out my 10 amp digital multimeter.

 

[Bob]

(quoted from post at 15:23:19 07/30/16)

(quoted from post at 12:35:37 07/28/16) You say it's still a 6 V system, so no ballast resistor is needed.

What is the battery charging voltage... should be around 8.4 Volts for a 6 Volt system.

Other than that, it seems you have a "bad" coil.

Only 6 volts across the battery when running, but the amps across the coil with the neg grounded maxes out my 10 amp digital multimeter.

Your digital meter may be confused by the electrical "noise" generated by the ignition system.

Measure the primary current with the engine NOT running, with the breaker points closed. You are looking for a reading in the 3 Amp range. If above 4 Amps or so coil will heat and point life will be shortened.