Installing the Modern Seal for the Camshaft in the Model T Ford

Installation is simple and in a few words; remove the tin shield and felt seal from behind the timer rotor, roll a bit of shim stock up inside the new seal, slide it over the camshaft and cam gear retaining nut, and slide the seal in place, “flat side out”. Note that some early cam gear cover castings will not accommodate this modern seal….the casting must be machined or changed out for a later casting.

In a few more words with pictures, the seal installation follows:

First, remove the tin shield from behind the rotor and the felt seal from the groove in the casting. Note that the seal does not ride on the camshaft, but rides on the nut that secures the cam gear to the camshaft.

Next, cut a piece of “shim stock” from an aluminum soda can about three inches square.

Roll the shim into a cylinder and insert it into the seal. Note the outside of the seal is the “solid” part

Place the cylinder over the camshaft and camshaft nut and slide the seal into place.

In case the seal does not fit snugly in the casting, use a bit of RTV bathtub seal to secure it.

If there is sufficient access, the seal can be slightly expanded using a drift punch along the face of the seal.

The seal is now installed and the rotor can be installed and tightened.

Note that the cam gear nut should not protrude beyond the camshaft boss for proper rotor clearance.

See the section on “Thick Cam Gear Webs”.

Install the pin, pin retainer and nut.

Note on some early cars, the pin hole went all the way through the camshaft, so if your car refuses to run after changing the timer, rotate the rotor 180 degrees on the camshaft and try again. (My 1912 is this way)

The rotor is now installed.

Transfer the wires from the old timer case to the new one. It might be best to “nest” the cases together and transfer one wire at a time so the wires won’t get mixed up.

Make sure that the terminal faces the front of the case so it cannot possibly ground out on the front of the engine.

Check the timing every time a timer is changed by removing No. 1 sparkplug, (or better yet all of them, regap to .025 inches) and place the plug(s) on the head connected to the plug wires. Using a flashlight or something to “feel” the piston’s travel, rotate the engine using the crank to that the piston has reached the top of its travel and has just started downward. This is the point that the plug should fire. Rotate the timer until the plug fires, then turn the engine over several cycles to make sure. See the section on “Changing a Timer” for more info.

User assumes all risks.

Frank’s Timer Service, 2251 Morgan Lane, Ingleside, TX 78362

Telephone: 361-230-0318, E-mail: Frank@andersontimer.com www.andersontimer.com