Lost spark on a C (non Magneto)

atlarge54

Member
I just went through the engine on a C and when I put the ignition drive assembly on I used a new gasket. When the engine came apart it didn't have any gasket there, any chance my ignition system now lacks an adequate ground? I've got 12v at the coil but no spark. It was at the end of the day and I didn't play with it too much, just thought about it on the way home it might just be a lack of ground.
 
The bolt(s)/stud should ground it even with a gasket.

You can quickly check with a test light to see if the distributor body is above ground potential. (VERY unlikely.)
 
As Bob says plus it would ground where it slides into the engine and at the gear that drives it. More likely you need to clean and adjust the points
 
Do you have 12V at the points when holding them open? If the points are closed you will not get a reading anywhere between the coil and points. Do you by any chance have the rotor in your pocket?
 
If you run through my Troubleshooting Procedure it will help diagnose the cause of no spark.

If you place a test lamp on the coils high input it must glow when the ign switch is on. Put it over on the coils low output (to distributor) terminal and it needs to be ON when points are open but OFF when they are closed. If it never goes off (should with points closed) the poinst arent providing a good ground.

My procedure tells how to do all this

http://www.ytmag.com/cgi-bin/viewit.cgi?bd=farmall&th=5745

John T
John Ts Troubleshooting
 
Thanks for the replies. I didn't have the rotor in my pocket, I did try holding the coil wire near the block though. It was near the end of the day and I just wanted to see if it would fire up, so I didn't even clean up the ignition assembly. The unit was greasy and well painted (red) I think it might be IH, that's why I wasn't too sure about the unit being grounded. I've got a working magneto on the shelf but thought I'd stay with the coil/batt system as magneto parts seem a bit pricey.
 
Even though the ignition worked fine when removed the points were soooooo bad they wouldn't conduct any electricity. Off to NAPA and $28 lighter she's running fine.
 

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