Interesting problem solved on Farmall A

I have a 1942 Farmall A that I bought with the intention to restore. The tractor had been owned by a "father and son" who had performed a "git 'er runnin'" "restoration", plus a 12 volt conversion.

So, I won't recap all of the things they did to it, and let's get to my adventure. The A had the Delco verticle distributor on it, and I wanted a magneto. Not a big deal, so I get the distributor and associated wiring removed. Get the engine on TDC. Go to put the mag on, and the old girl doesn't line up for #1 on the cap. So, I fiddle a bit, trip the impulse, and get it close. STarts up, but is way advanced on the timing, and runs like crap.

take mag back off. Set to TDC again, same thing, coupling doesn't line up with #1 on the cap. Scratch my head a bit, and take the govenor off. Pulled the govenor shaft, and yes, it was 4 teeth out of time. I guess it didn't bother the previous owner as they just adjusted for the out of time condition with the distributor. So, I get the gear timed on the govenor shaft, and put her all back together. fired on first rotation, and runs like a champ.

Just thought I would share because it was an unusual problem.

Happens a lot more than you'd think. It's one of the peskier problems to identify. Good work on noodlin' it out and gettin' it done!

Thanks Scott, I appreciate the kind words. That is why I posted it, as someone else may run into this at some point. Not quite sure I would have figured it out as quickly if the previous owner hadn't stated that, "they had the engine professionally rebuilt".......God knows that is becoming more and more of a scary statement on this site!

It ran like a champ with the distributor, and it just didn't make sense that the mag wouldn't time right. It then dawned on me that the distributor was 360 degree's adjustable for the timing..... not immediately obvious. And the only way for a mag to out of time is if the pinion shaft is out of time or the mag internally is out of time.

I had a similar issue with an F-4 mag, but in this case, it was the mag being out of time internally. Bought it off a guy who was getting out of tractors. He told me how he rebuilt it. Threw a decent spark, but was once again couldn't get the tractor to run right, as when you would advance the spark the engine would spit and sputter and die. Also, the impulse didn't seem to trip at the right time. Spent 2 weeks monkeying with the timing disk on the mag drive, but couldn't seem to get it right. Then on a lark, I opened the mag up and found the rotor to be out of time with the mag shaft. Got it properly timed, and ran perfectly. I am definately loosing faith in peoples ability to read directions............

Hopefully this post will help someone in the future with similar issues.