I know this is a subject that has been discussed at length, but I searched and couldn't find an answer...
New Kevlar bands installed with hogshead off and metal band double checked for roundness
Good drums, no cracks
Newly rebuilt engine.
Inially set the bands loose and made minor adjustments until they stopped slipping. Low and reverse are ok now.
Brake band was adjusted up so it stops the car. Not locking the wheels up, but enough to stop the car.
I took the inspection cover off the trans and noticed it seems hot.
Thinking I might have a dragging band, I put the cover back on and let it cool down. Jacked the rear wheel up and let it run in high for a couple of minutes, to get the drums spinning.
After removing the cover and feeling the drums, the clutch and reverse drums are not hot at all, and the brake drum is fairly hot, but I can still hold my finger on it. If I loosen the brake band any more, I will have hardly any brakes. Do I just need to let them seat in some more?
Kevlar bands will create (and absorb) a lot of heat.
Remember, do not 'slip' the pedals like you would normally do with the clutch and brake in a modern car. With the low and reverse pedal, apply firmly to stop the drum. With the brake, apply firmly and release, apply firmly and release.
Slipping the pedals ESPECIALLY with Kevlar bands, will quickly gain you membership in the 'cracked drum club'.
That is exactly how I was taught on my grandfathers '23. I still drive them like that. A good firm stomp on the pedal for low or reverse, and when stopping, firm push on the pedal, then let up to get some more oil in the band and repeat. I still remember him smacking me on the shoulder and telling me to let up on the brake pedal . Our '27 had kevlar in it, and we didn't put tons of miles on it touring, and we never even had to adjust the bands for years. I guess I just need to get these brand new ones broken in and seated.
Greg -- It does take some time for new bands to seat. Typically, you will need to readjust kevlar bands two or 3 times, until the fibers are compressed and they become fitted to the drums. After that, you probably won't need to adjust them for quite some time, maybe a year or two. I recommend adjusting them so that they engage firmly just an inch or so above the floorboards.
Is the cam for the brake band worn? If the cam was not replaced and is worn you will have to tighten the band way too much to get decent braking and as a result the band will drag when the pedal is not being depressed. If you back it off so it does not drag you cannot get the band to contract enough on the drum for a good stop because the cam is worn.. If you suspect that might be your problem I believe you can easily change the cam on the brake pedal and the reverse pedal in the car (not so for the clutch cam). As a quick temporary fix you can put washers on the pedal shaft right behind the ears on the band but be careful they don't drop into the crankcase.
I'm not sure I understand the washer trick. What does it do that tightening the nut doesn't do? If the cam is worn, the pedal has too much free play before the shaft starts moving sideways. I don't understand how putting washers behind the band ears reduces any free play in the rotation before side movement takes place. It seems to me that putting washers behind the band ears is the same as tightening the nut except it pushes the left ear to the right instead of pushing the right ear to the left. What am I missing?
My understanding is that as the band wears and more and more adjustment is put in, the adjusting nut side of the band gets pulled further and further away from vertical and towards the pedal side. Inserting the right number of washers on the pedal side of the LH band ear moves the ears of the band over to a more vertical position. This reduces the tendency of the RH band ear to be pulled down and dig into the drum.
Instead of adjusting "till they stop slipping", try this for the low/hi pedal, which I think is the hardest to get right:
Adjust so the pedal is 1/2" to 3/4" with a moderate to high amount of pressure on the pedal. Certainly as hard as you can push with your hand(s). When adjusted right it should be virtually impossible to push the pedal to the floorboard even using your foot.
That's always worked well for me.
Thanks for the info guys. I'll make another adjustment and take her for another quick trip - makes a great excuse to get it out for a spin! A little cold, but still fun!
After adjusting the low pedal, press it really firmly with your left foot and make sure that the pedal pops back up when you release it, i.e., it has no tendency to "stick" in the down position.
Mark has it right on the washer issue. Believe me it works as a temporary measure. My problem was with the low speed band and that requires pulling the hogs head to change the cam. I needed the car for a week long tour and did not have the time to make the proper repair. I remembered reading about a back yard repair for my problem in Tinkering Tips and gave it a try. It worked so well that I used the car for the rest of the year without issue and didn't bother to make the correct repair until I put the car up for the winter a year later.
Since we are on the band issue again, let me add to the question. I have kevlar and do not have a problem with low and reverse but have had to adjust the brake frequently. I have been driving T's for 30 years and try not to use the brake until the last minute at a stop light when I'm just about stopped. Also, when I open the cover there is a lot of lint. I expected that when I first installed the bands but it continues. I seem to have plenty of band material left. I thought maybe the washer was warn and kept slipping on the brake band. What do you think?
Sounds like you have a cracked drum.
Lots of lint and having to constantly tighten the low band were the two hints my 27 Roadster gave me. It wasn't until I removed the bands to reline that I saw the multiple cracks in the low drum.
That was with kevlar bands btw.
I would agree with you Mike. I tried an old trick to see if there was a crack. I took some carb cleaner and sprayed it on the drum as a partner slowly turned the engine over with the crank. Not a trace of a crack. This technique has found cracks before. The carb cleaner evaporates quickly except where there is a crack. It stays wet in the crack for several minutes. I don't like the idea of taking the engine out but maybe that is the only way I can be sure and perhaps avoid a disaster.