Goose
Well-known Member
A week ago, I posted a thread about an M Farmall I'd bought on an auction that would run fine when pulling, but ran rough under no load or light load conditions. It also smelled of stale gasoline.
I put fresh gas in it, boiled the carb and put a kit in it, serviced the air cleaner, etc. Nothing helped. The distributor cap, rotor, and plug wires looked new. The points were OK.
I then pulled one of the spark plugs and saw it was an Autolite. I smelled a rat right then, 'cause I once had a Chevy pickup that needed new plugs. I put a set of new Autolites in it and it ran worse than with the old AC's. I then put a new set of AC plugs in it and it ran fine.
Upshot on the M was, I had a new set of the correct Champion plugs on the shelf in my shop I'd intended to use on an H. I put them in the M and it runs fine.
I didn't suspect the spark plugs because they usually act the opposite, they'll misfire under a heavy load and still run OK under a light load.
BTW, a bit of trivia. Do ya'll know that AC and Champion spark plugs are named after the same man? Around 1910, when the automotive business was in its infancy, a man named Albert Champion started a company manufacturing spark plugs and branded them "AC" after his initials. He ultimately sold the company to Buick, which is why to this day GM uses AC spark plugs. Mr. Champion then started another company manufacturing spark plugs and branded them "Champion" from his last name.
I know some of ya'll have been losing sleep wondering about that.
I put fresh gas in it, boiled the carb and put a kit in it, serviced the air cleaner, etc. Nothing helped. The distributor cap, rotor, and plug wires looked new. The points were OK.
I then pulled one of the spark plugs and saw it was an Autolite. I smelled a rat right then, 'cause I once had a Chevy pickup that needed new plugs. I put a set of new Autolites in it and it ran worse than with the old AC's. I then put a new set of AC plugs in it and it ran fine.
Upshot on the M was, I had a new set of the correct Champion plugs on the shelf in my shop I'd intended to use on an H. I put them in the M and it runs fine.
I didn't suspect the spark plugs because they usually act the opposite, they'll misfire under a heavy load and still run OK under a light load.
BTW, a bit of trivia. Do ya'll know that AC and Champion spark plugs are named after the same man? Around 1910, when the automotive business was in its infancy, a man named Albert Champion started a company manufacturing spark plugs and branded them "AC" after his initials. He ultimately sold the company to Buick, which is why to this day GM uses AC spark plugs. Mr. Champion then started another company manufacturing spark plugs and branded them "Champion" from his last name.
I know some of ya'll have been losing sleep wondering about that.