JD MC no spark

samhell

New User
My MC is not getting any spark, and I would appreciate any input. It turns over, and has fresh fuel. I pulled a plug and held it to metal while turning it over and got no spark. I used a tester light and it lit up when touching either terminal on the coil. It lit up on the external wire connection on the distributor, and lit up inside the distributor (points etc) It would not light up when touched to the coil to distributor wire nor the plug wires (Even while cranking)
Before I just started buying parts and guessing, I thought I"d see if anyone had any thoughts
Thanks,
Dan
 
The FIRST thing to check is the points .. If badly burned or pitted or oxidized a good cleaning and/or points file may get her going. Check for proper gap and that they are opneing and closing.

A test lamp on the coils input voltage should light anytime IGN is ON but usualy when shes sitting there not running with IGN on the coils output to distributor doesnt read voltage cuz the points are usually closed. A lamp on the coils out or dist side terminal should flash on (points open) and off (points closed) if the engine is being cranked over.

Run my Troubleshooting procedure

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

John T
John Ts Ignition Troubleshooting
 
600 grit w/d sandpaper works well. 1 sheet of the stuff could last a lifetime. Cut a 2" x 1" chunk, fold in half longitudenaly (sp) and apply to points (when closed- I do this process with NEW points - helps them 'mate' (giggle). HTH
 
I had this with my MT and I ended up with two issues. First issue was the resistor on my switch was no good and had rotted away which also popped the fuse. Once I fixed that I still didn't have spark because I had a bad condenser. Replaced the condenser and it was been starting great since. I didn't replace my original on/off switch I found some new resistors and soldered them in place of the old one. Cost about $8.
 
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