1948 cub ignition

[Tahj]

Hi,

I am working on a 1948 Farmall Cub. The owner picked up a tune up kit that consisted of plugs, wires, points, rotor and condenser. We installed the plugs and wires, and removed the distributor cap. The rotor is mounted under a plastic retainer. I removed the retainer and found the rotor was mounted on a shaft and geared to a smaller drive gear. The replacement rotor from the kit looked similar but had no gear on the underside, more like an automotive rotor had a key to lock its rotation to the shaft.

I removed the geared rotor without marking its location and on reassembly the engine appears to be out of timing.

From an aftermarket parts manual there appears to a pocket under the rotor plate for points and condenser. The rotor, cap, and magneto are mounted closely to the oil filter and I was unable to remove the three screws from the plate over the points.

How do I retime the rotor?

[Waif]

Check out Glen's picture on the linked thread to see if it's the timing/alignment you need for rotor/gear.

Your description of the new rotor received from whomever scored your parts hints of a distributor style rotor. The magneto rotor costs a bit more, and as you have noted ,is differently configured in design.

viewtopic.php?f=1&t=106197

[Glen]

Hi,
The Cub operator's manual will help you learn about maintenance that the Cub needs.
Below are pages from the 1947 Cub operator's manual showing the magneto.

http://farmallcub.com/rudi_cub/www.clea ... age-30.jpg

http://farmallcub.com/rudi_cub/www.clea ... age-31.jpg

Use a short screwdriver, with a sort of wide blade to remove the 3 screws holding the cover over the ignition points on the magneto.
You would need to install the rotor in the same position that it was before, for the magneto to be timed correctly, if it was timed correctly before.

Below is the 1949 Cub operator's manual. The experts on here recommend people read it. It has lots of info about operation, maintenance, and lubrication. There is a table of contents on page 1.
It shows how Cubs originally looked in it. The lube section begins on page 14. Changing the trans and final drive oils are on pages 20 and 21.
Maybe you can give it to the owner, if you are not the owner.

http://farmallcub.com/rudi_cub/www.clea ... index.html

The recommendation in the manual to use motor oil in the Touch Control was changed later to use Case IH Hy-Tran fluid. It is sold at Case IH dealers.

It sounds like the rotor that came with the kit you have is for a Battery Ignition unit, they are different than a magneto rotor. Battery Ignition came out in 1950 on Cubs.

[staninlowerAL]

Welcome to the forum. After your second post you can access and download the service manual GSS 1012 for the cub ignition systems. It covers all the service, maintenance and repairs of the Cub ignition systems.