Gemmer steering box abuse and repair

This little Gemmer steering box has been just fine on this car. A faster ratio would be nice, but it's not been a serious problem. It is an old fashioned but quality system, pretty much trouble free for 50 years, but eventually the pitman arm bushing develops wear and gets sloppy.

Leak it won't though; it's cleverly designed to have no seals below the oil line; the pitman arm comes out of the top of the box (severely limiting modern replacement choices, to zero).

I did manage to make mine leak, more precisely, dump all of it's oil on the ground. It is a simple worm and sector design; lateral chassis load (in countless severe turns at speed with very large and sticky tires) transfer side load in turns onto the steering arms, the tie rod ends, to the steering link, to the pitman arm. The forces on the pitman arm are countered by my arms on the steering wheel; in the middle of this is the little wormgear on the long steering shaft and sector gear on the pitman arm.

In hard left turns the pitman arm is trying to press the steering shaft (with me and the wheel on it) up, and on hard right turns, pressing the steerign shaft down. This puts load on te taper bearings, but they're adequate (just). THe problem is that the lower steering shaft bearing is mounted on the little four-bolt cover plate, and beign under a 1/4" thick, it bends under the load.

Crash into a hillside in a tight turn and this gets a little worse. (I was getting tired and I should have slowed down.)

If this happens again I'll fabricate a stiffer end plate, but there are only four shallow small bolts holding the cover on, so no matter what, everything has a limit.





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