TC Tomkins box

[tcremesal]

Have any of you fellas installed or refurbished a Tomkins steering box modification . My TC was never driven much , but, neither was it fitted or maintain properly. I've opened the box , void of any lube, but the sector shaft and peg have no wear and fit tightly through the hole. Worm assembly has no wear either. I've ordered modern type seal from Moss. Is 600 weight oil (Ford Model A rear end oil) the preferred lube? Any things I should avoid or any tricks ? As always , Thanks, TC

[stephen stierman]

How does the car drive? If you have looked at the peg and seen no side wear, and there is not a lot of lost motion on center things are probably within reason for a TC, but the kit does allow adjustment to be a bit simpler. The Tomkins kit is just supposed to push the peg deeper into the worm with the idea of reducing lost motion. It is not magic as most steering boxes had this feature built in. The same affect can be had by reducing shims on the top cover, but the Tomkins kit makes it easier, although there is a tendency to crank the adjuster down too tightly making the steering much too stiff. Keep in mind that steering feel and accuracy is also affected by many variables: toe in, which should be properly set and making sure the peg is at the high point of the cam while in the straight ahead position, which can be achieved by adjusting the length of the drag link.

[Gene Gillam]

This is an excellent primer: http://www.mg-tabc.org/library/Buell-TC ... 3rd-ed.pdf

Interestingly enough I had to do a web-search for it...I couldn't find it here on the site although it has a TABC url (I think that's what it's called).

[frenchblatter]

One of the first things I was taught in January 1961 when I started as a very young 15 year old apprentice was to never turn a Midget steering when stationary. Not talking about the Spidgets, but the M, J, P, and T types.

With a very limited lock this made getting the cars from the basement car park area to the workshop very hard work.

By the way, the workshop had floor to floor lifts that worked on the water pressure of the underground River Fleet. Pull the rope one way and the valve let the water pressure lift the lift and pull the other rope opened the release valve for the lift to go down. I guess they're still there as the old workshop in Carrington Street is (or was) an NCP car park.

[Duncan M]

2X on only turning the steering wheel with the road wheels turning (on the ground) . To do otherwise will damage the top/outer edges of the "worm." The 600 weight Ford oils are a trade name and not actually 600W. The viscosity of 600 weight should be somewhere around 250W gear oil. The thing to always avoid in the steering box is grease of any kind, as it will not lubricate the ball bearings. When adjusting the BC box shims, remember the end plate also requires adjustment--first. If going to a Tompkins type kit, the condition of the sector shaft should be evaluated--first.

Note "photo 3" and text above and below it regarding potential damage to shaft from a Tomkins type kit--from this outstanding article

http://ttypes.org/ttt2/?s=straight+and+ ... mit=Search

Pic/diagram below, showing general layout of BC box, is from this (above) article.

EricWorpeFig1.jpg (251.54 KiB) Viewed 6753 times

[tcremesal]

Lots of info . Thanks. I assume new modern seal should be installed cup side up ? TC

[Gene Gillam]

Yes...lip up, metal to the bottom.

[tcremesal]

Mine came without. diagrams unclear.Doe's it fit bottom of sector shaft outside of box , or inside where sector shaft slides in?
There seems to be a recess inside on top for seal . Thanks Again

[tcremesal]

Bottom I see

[tcremesal]

Any tips for removing the existing seal from the bottom of the steering box would be greatly appreciated Thanks, TC

[Gene Gillam]

Can't you remove the sector shaft and then pry it out?

[tcremesal]

Got it off. New one on . Just ordered 600 wt.oil. $9.00 +$15.00 shipping!! Does one have to make a paper gasket for the top ?

[Gene Gillam]

I don't think so...why not use gasket cement between the top and the case?