My Great Grandfathers 1947 Cub!

[k hutchins]

In my opinion, l would set your tractor at TDC then remove the mag.
If you're replacing the coil, condensor, and points, it makes it a whole lot easier to work on because you have to fish the wire down through to the bottom through a grommet (if it's still there). You can set the points easier by watching the cam if you spin it backwards then set them on the high side.
Then get your rotor set to the 1 oclock positon and remount the mag, setting up for static timing per the owners manual (coil toward the block) crank it back to #1 TDC, then rotate the top away from the block until it "snaps" tighten it into place and you should be good to go.

[Glen]

Hi,
The post above gives good advice.

The coil cannot be replaced without taking off the cover over the points, that the rotor is on.
The cover is held on with 3 screws.
The coil has a small wire that goes through inside the magneto, that has to be in the right place.
While the cover is off is a good time to replace the points.
I put a link to new points and a new coil at one of your posts before.

I would read about the magneto in the 1947 Cub owner's manual, and become familiar with it, before working on it. Pages 30 - 32 have info.

Step 2 on page 32 tells how to find number 1 cylinder TDC.
The page tells how to time the magneto to the engine, when you are done repairing the magneto.

The rotor is gear driven. The manual says to grease the gears under the cover that holds it on, the cover with the 2 screws.
Clean the old grease out, and put in new grease.
Check the teeth of the 2 gears for wear and replace the rotor and drive pinion gear if needed.
TM Tractor has a new rotor, and pinion gear if you need them.
The 2 gears have timing marks, check and align the marks while the cover is off.
Below is a pic of the timing marks.

[Gary Dotson]

No problem, Frank, that was one of easiest all week-end. I agree with Hutch, much easier to make it a bench project.

[AHS]

Ok, ALL great tips!! Thank you! The engine is at TDC #1. I’ve got magneto off, and I marked two spots, where the rotor cap was on the housing. I marked the retarted-advance spot. I should have marked the rotor to the small gear, but they have marks, (Glens picture). Now that I’ve got the magneto off, I can set the points to .013”. I am gonna take the magneto to Ebersons electric repair shop, just to see if the magneto can handle it! The magneto is gonna be spun, just set my points at .013”, align the marks on the rotor button, and put the rotor cap on and it’s all set? Or am I missing something?

[Cubfriend]

Make sure when you spin the mag that it can go to a good ground otherwise some damage could occur.

[Glen]

Hi,
They have said on here don't turn the magneto at the drive end, and make it snap, if it is disconnected from the spark plugs, it can damage the magneto to generate power with no place for the power to go.

If you are not replacing the points, file the point surfaces so they are flat and shiny, and set their gap.
Wipe off all filing with a clean rag.