Adjusting the parking brake on the T, I have a question.
Adjusting according to the Service Manual, I discover that no amount of adjustment results in both sides being locked tight. Either one side is or the other side, but not both.
I adjusted the driver's side to lock tight when the brake handle was all the way back. But by the time the passenger side is adjusted the driver's side is now movable with some effort.
Would replacing the brake cams take care of this problem?
Let me also add that the emergency brake handle after adjusting the passenger side, doesn't remain in the same place as it was when only the driver's side was adjusted. The additional pull causes it to be in a different place (not all the way back).
Most likely. Best to remove all the slop and get back to factory almost new. New bushings in the backing plate, and then the new cams.
Check the clevis pins for wear or replace too. And the brake rods, if they are worn at the clevis.
All that assumes the brake shoes are both alike and even with little wear too.
What makes it tricky is that on the driver's side, the brake rod attaches right at the bottom of the stick. The passenger side rod however, is attached to the lever arm that is at the other end of the emergency brake cross shaft, i.e. the shaft that takes a dip under the tranny no less. Therefore it will take greater travel of the stick to exert the same braking effort on the passenger side due to twisting in the cross shaft.
Also realize that with only one brake attached, all the effort you put into pulling the stick goes to only one brake. With both attached, divide the resultant braking effort by 2.
Probably all you can hope for is to get it close. That is the big advantage of hydraulic brakes, the exact same force is applied to all brakes at the same time.
For what it worth---I added a bit of weld on each side of the clevis and ground smooth.This gave me additional brake shoe "lift" without the problem of replacing the bushings, etc. (pretty loose). A good "interim fix", for now....Paul
One of the most important aspects of the pre-'25 model T parking/emergency brake is that the cam lever needs to be almost straight up at the point the wheel is locked. That is the moment of maximum leverage (pull) which will allow you to lock the brake. If that point where the wheel is locked has the levers forward of straight up, either new cams or shimming the cams is necessary. If the shaft and/or bushing is worn much, new cams and bushings is best. If the shaft and bushing are okay, I make a steel shim to go all the way around the cam. It needs to be custom made to fit. Thickness depends upon the amount of wear you are trying to eliminate. Sometimes, not always and depending on thickness and fit, I tack-braze the steel shim onto the cam. Check the fit between the front of the cam and brake drum. Make sure it won't hit.
You will likely need to do some grinding/fitting on the shoes or enlarged cam to get it to lock at that best point.
The first thing is to make sure the shoes and drums are good.
I prefer the lined cast iron shoes. The ones that have been available for years have some fit and trim issues, but once set up right, work very well. Some maybe better ones are now available, however I haven't used them so I can't say whether they are better or not.
Small drum, good lined cast iron shoes, should be able to lock the wheels at speed if you have to. Their shortcoming will still be that they are under-braked and will wear and need additional attention because the surface area is too small. However, as long as they are reasonably maintained, they should be "adequate" as an emergency brake.
Drive carefully, and enjoy, W2
I'll do some more experimentation.
I plan to replace the pawl on the brake handle so it grabs better and then we'll go from there.
Are you sure the cams are on the correct side of the car? They come in rights and lefts and if you have two rights or two lefts, the lever will be in a different position on one side. For example, on the correct side, the lever is straight up or nearly so when it locks. If you have one where the lever is quite far to the back when it locks, you have the wrong cam on that side and you will have problems with your adjustment.
Also if you adjust the passenger side first and pull hard on the hand lever, it is possible to twist the shaft. Since the clevis on the drivers side is an extension of the lever, it will be at a different angle because the shaft has been twisted. So check to be sure both levers on both ends of the shaft are in the same position.
The way I adjust is to push the rods as far toward the back as they will go without bending and adjust so I can just slip the pins in without any bending of the rods with the hand lever all the way forward. Then pull on the brake on and check which wheel locks up. If one locks up and the other doesn't, tighten the one that's loose by one half turn. Try again. Keep adjusting by one half turn until both wheels lock at the same point of the lever.