Farmall Cub

Greenthumbfarms wrote:The temperature here dropped last night, and I think I'll wait a few days for it to warm up before I work on it again.

I've read about timing the mag, the "snap" I'm listening for...it would be an actual sound? Or the Mag shifting when number 1 hits TDC?

Peter Person wrote:Yes, it’s an actual sound.

An audible click. Can't miss it.

Although I haven't had a chance to re-time the tractor, I did check the spark today. A nice, blue spark off the m center wire from the Mag, so it looks like it will be a timing issue.

I timed the mag this morning, it's still giving me trouble with kicking the starter out as soon as I pull the ring. I don't know if my starter drive is shot or if I need to look at the points. Any be thoughts? Now it just wants a drip gas out the Overflow hole in the carburetor after it kicks out a time or two

Hi,
Good that you set the timing.

I would look at the spark plugs, they need to be clean so the engine will run.
If the bottom end of them look wet with gas, dry them.
If they are oily, remove the oil.
If the contacts are black, use sandpaper and remove the black, and shine them up.
Check the gaps, they should be .023".
Spark plugs can quit, and not fire, then the cylinder won't fire.

The starter drive is probably working normally, it is supposed to kick out when a cylinder fires.
If other cylinders are not firing, the engine won't run.

If the points haven't been serviced lately, I would look at them, and file or replace them if needed.
TM Tractor has new points.
The Cub owner's manual shows how to get to the points, and has pics of them in the magneto.

I would charge the battery fully, use a small output battery charger, and let it charge slowly.
A 6 amp charger is good, one that automatically slows the charge rate as the battery charges up.

It is normal for the carburetor to drip out the bottom drain hole if the engine doesn't run after running the starter.

Well I pulled the mag to check out the points...I dont think anyone has been inside for a long time, one of the screw heads rounded off.

Can a slot be cut with a dremel for a screwdriver head to remove it? I had figured on replacing the screws

You could use a power tool, if you have something that will fit in the small space.

If the magneto was held in position, in a solid holder, you could try using a large screwdriver, wider than the screw slot, and hammer the end of it lightly into the screw slot. Don't hammer hard.
Wear your safety goggles in case the end of the screwdriver might break.

A screwdriver that fills the slot is needed to prevent slipping.

Since you have the magneto off, it is a good time to grease the rotor drive gears.
Remove the 2 screws holding the cover at the rotor.
Clean the area under the cover, and grease the gears.
Check the timing marks on the gears, they should align when the rotor is pointing to number 1 cylinder.

Below is a pic.

From looking at your pics l would say you would be well served by a basic mag tune up.
Points, condenser, rotor, and cap.
The rotor looks well tarnished and a bit scored or burnt on the end. That leads me to believe the inside of the cap is the same. Points that are shiny and new will work better than just dressing and resetting the gap on old ones.
If you're like me you'll save the old parts for spares just in case.

Just my two cents, Glen has you covered with the technical stuff.