Coil Confusion

[23 Reo 229]

I need help, no spark. I think I need a new coil on my Raider 14. Points look good, cleaned, gapped to .020 and a new condenser. On one condenser post there are the points and the condenser.The other post has a wire going to the dash. Is the condenser side negative and the other positive? If I get a new coil how do I Know which posts are positive and negative? How do I check the coil with a meter? Should I just pull the coil from my C-165 (it has spark) to determine if the coil is bad?

[squonk 43,447]

Coils hardly ever go bad. If they do usually oil is leaking out. A new coil will be marked + and -. A new coil from Napa would be  # IC64SB

 

Do you have a 12 volt test light? If so with the key switched to start you should have 12 volts at the + terminal. At the negative terminal the light should flash while cranking. If it just stays on your points aren't opening to break the primary circuit of the coil. If you have no light at all on the neg terminal it means your coil has an open primary winding. 

 

Your points have to break the primary circuit of the coil to cause a magnetic field to collapse which induces the high voltage in the coil secondary circuit.

[953 nut 59,326]

6 hours ago, 23 Reo said:

Should I just pull the coil from my C-165 (it has spark) to determine if the coil is bad?

If you have 12 volts going to the "+" terminal of the coil you can remove the spark plug and use a screw driver (don't touch the metal part of the screw driver, shocking) to open and close the points to  see if there is spark. If there is no spark unhook the condenser as a test and open and close the points. If you have spark now it is the condenser.

As Mike said it is unusual for a coil to fail but I would try a known good used coil before buying a new one to be sure.

[23 Reo 229]

Thank you, I will test tomorrow.