Steering Box and Pitman Arm
Way back in the 60s, when we were driving the car a lot, it's steering box was worn badly so that the steering wheel showed free play of about 1/4 turn. That being not safe, I determined to fix it. In the steering box, I found a worm gear at the end of the shaft with a brass sleeve that rode end-to-end on it that actually turned the output shaft. The brass sleeve was badly worn so I tried to get a new one made. I could not find a machinist willing to make one. The thing had four sets of threads. There was no internet yet so a locally found replacement seemed the only option. The closest thing I could find was a complete box and column from a later 100E, I do not remember the exact car. I should point out that I am writing this in 2026, some sixty years after discovering the worn brass slider.
The box was a little bigger and the shaft, from box to wheel, was almost a foot shorter. Some alterations would be required. Instead of the brass slider, it used a more common worm and peg actuator. The worm was nothing like the one on my shaft. I cut both worms off and welded the new one to my existing shaft. Actually, I think I probably had a professional do it for me as I don't believe I even had any form of welding equipment at the time. I removed the shaft tube from the box and added mine to it instead, being sure to keep the overall length correct. A shop-made bracket, bolted to the frame provided a suitable mount for the box. The small end of the pitman arm would not fit the tie rod end on my drag link so I cut the ends off both and welded the '48 end onto the newer arm after carefully measuring to determine the desired length. I got this wrong, on the short side, resulting in a large turning circle. It usually worked all right, except for a maneuver like turning into a driveway from the closest lane. I determined to fix it someday by making a longer arm but this would require another 100E arm. Some time, after the internet, I purchased a complete box with pitman arm and column from eBay to get that arm.
While trying to get ready for the All British Car Show in 1998, when I had the axle removed, I removed the shaft and had a professional machinist reinforce that joint by welding a sleeve over it. When I finally started the total restoration I discovered the box would not hold oil. It would dump its entire contents within just a few days. After replacing the end gasket it still promptly emptied, I determined the oil seal on the pitman arm shaft must be the culprit. This meant the box needed to come out of the car for repairs. I raised the car as high as I could with my jack, dropped the axle and spring to the floor and removed the oil filter. I still had to remove the top from the box before it would clear and come out between the frame and the spring.
All seemed in order until the column suddenly hit something solid. The fixture at its top is held on by four rivets that made it too big to fit through he hole. I ground their heads as much as I safely could and tried again, with the same result. There is a wider extension at the very top end that is also larger than the hole. My solution was to remove the box from the tube along with the steering shaft then pull the tube from inside the car.