I am just finished with some overhauls on my 1946 TC and thought I would pass along a couple of the more arcane items that I ran into. Perhaps these are documented somewhere, but I have searched in vain.
TC Gas Tank Sending Unit Leak
How many times have you walked down the line of TCs at a Concours and noticed discoloration and weeping around the Gas Tank Sending Unit? Mine did for years and I went through an endless supply of seals and sealants looking for the answer. Recently, I took long look at the problem after replacing both the sending unit (thinking the cover plate was warped) and the seals, along with some sophisticated gas-impervious sealant that a friend at Emhart gave me. Rotten beast was still leaking!
Then I looked closer and noticed the upper left ear of the Sending Unit was shiny, indicating that it was rubbing on the spare wheel angle bar just above. Further thought led to a guess that road rattle was causing the gas tank to move up and down slightly (yes, I did check the straps and they were nice and tight) and breaking the seal of the unit. Further thought also led to a conclusion that the pads fitted between the base of the tank and the frame were too thick, leaving inadequate clearance between the Sending Unit and the angle bar. Removed tank, cut pads to 1/2 dimension and refitted. No leaks!
TC Steering Wander
After you have followed all of the wisdom on restoring your TC steering, did you find that you still have lots of play in the steering wheel? The answer is a combination of "not quite centered" and "incorrect end-play". Minimizing play in the Steering Wheel requires dead-on centering.
Remove the Drop Arm from the Sector Shaft. Measure front and rear track on the wheels to ensure they are perfectly straight ahead. Spin the Steering Wheel from lock to lock (several times to get it right) and center the steering wheel. The splines on the Sector Shaft are close set to allow a very precise centering, take care in re-fitting the Drop Arm to capture the closest spline possible.
With the Steering dead on straight, if you still have excessive play at the Steering Wheel, the problem is incorrect endplay. There are shims between the base plate and the Steering Box that control this play. You must fiddle with these until there is no play at the Steering Wheel. To do this, it is best to remove the entire steering column and box and make your adjustments on a bench.
With the box itself in a vise, first center the Steering Wheel by running back and forth from lock to lock and counting turns until you are sure the Steering Wheel is centered and mark this position precisely. Now, open the Steering Box and observe where the Sector Arm is positioned relative to the center of the box, mark that position on the edge of the box. Then, run the Steering Wheel from lock to lock several times and observe where the Sector Arm finishes at each lock. There most likely will be a difference. You will correct this difference with the shims. When there is no difference at the locks, you have the Sector Arm and its peg in the Steering Worm centered (note the difference when the Arm is centered between the mark you originally made and its new position). Refit to the car and center to the wheels as described above. Voila! Your TC steers like your daily commuter.
I have searched all over for how to deal with these two challenges and found no one who could spell it out. Forgive me if my effort is obscure.
Best of Luck,
Peter S. Roberts