Rule of thumb for band adjustments

[jiminbartow]

While I have had my Model T for 52 years, this next question has always been a concern for me and in all this time, I have never been sure whether I was doing it right or not. When adjusting the bands, it is necessary to find a happy medium between adjusting them so that they allow adequate oil between the bands and the drums, while also allowing for maximum grip when the pedal is pushed. What is the happy medium. I am adjusting my bands now and, as alway, am in a quandary as to what the most efficient adjustment is. Should it be so that there is very little play between the time you press the pedal until it makes contact with the drum or is there a more significant space between when the pedal is pushed and the band makes contact. How much space is needed between the bands so the oil gets under the band to lubricate the drum. Is there a lot of leeway here? In other words, can the oil get under the bands pretty much as long as there is even a small space between the bands and the drums? I have Guinn’s wooden bands that, when I installed them, I made sure they were perfectly round so that drag on one side or the other is not an issue. Jim Patrick

[Steve Jelf]

I've always been told to adjust bands so the fully depressed pedal is no closer to the floor than one inch. That leaves all bands at their maximum expansion until you step on the pedal. The Bible says "as loosely as possible without causing them to slip on the drums." I believe the one-inch rule does that.

[TXGOAT2]

I don't think oil getting under the bands is the issue so much as is preventing the bands from dragging. I like a "high" pedal, but I don't think that's good practice on a Model T. As long as the pedals stay clear of the floorboard from at least 1" to about 2" when pressed firmly, assuming the floorboard is in the correct place, you're OK. The T transmission is not a high precision assembly, and a lot of vibration is present, and plenty of clearance is needed to assure that the bands are not dragging under any condition. Worn linkage, weak springs, bent pedals, non-original parts, and so forth may complicate trying to get an ideal adjustment. It's very important that the bands have enough clearance to prevent drag. If they drag, you will have problems, sooner than later.

[speedytinc]

To adjust out all the drag for low pedal. With the engine running with the parking brake on, tighten low until you start to hear some triple gear noise change. Back off 1/2 turn. Lock it down. You are @ max pedal with no drag. The brake & reverse pedal adjustment is more of a guessing game without external band adjusters.

[Steve Jelf]

Is there an advantage to adjusting the bands so they are fully engaged with the pedal higher than an inch or two from the floor?

[MichaelPawelek]

On every Model T I have ever worked on the problem with getting the bands adjusted properly has been worn cams and bent pedal stems….

[TXGOAT2]

I don't think there's any advantage to trying to get a high pedal on a T. A high clutch pedal might might interfere with getting a good free neutral window, beside the risk of dragging bands. The T brake pedal acts almost directly on the brake band, without the rods and equalizers found on other cars. Under heavy use, the T brake drum might expand so as to actually tighten the brake, where as an internal expanding drum brake, such as used on the Model A, might tend to loosen under hard use due to drum expansion. I don't think Ford ever recommended trying to achieve a high pedal on the Model T. Obviously, all three pedals must have at least 1" of clearance above the floorboard at full engagement to assure that full braking and full band engagement can be achieved. Emergency brake adjustment is more conventional, but the necessity of getting a good free neutral while still achieving full emergency braking requires adhering to Ford instructions for adjustments.

[old_charley]

I was taught years ago to adjust the bands so that the pedal moves sideways 1/2 the ramp on the pedal cams. I have run across low pedals that have been bent down from the pressure of driving in low gear. As Michael stated, worn pedal cams require more pedal travel. That would make adjustment by pedal height problematic. With Kevlar bands, I prefer the adjustment to be with the most pedal travel that still gets a solid bite on the drum, regardless of any height measurement or sideways pedal travel. You just can't afford to chance any drag on the drums. That just takes a bit of driving and adjusting. I was told second hand, that Jim Guinn, who makes the wood bands, recommends setting a high pedal. The method that John pointed out works quite well for those. I found that setting wood loose causes the band to chatter when engaging.

[Allan]

Bryan has nailed it. Ramp wear, bent pedals, re-cut floorboard slots etc. make the 1" from the bottom of the slot adjustment rather serendipitous.
I use Kevlar bands exclusively. I adjust these so that they engage without slipping, just before the pedal bottoms out. That leaves them with the maximum clearance between band and drum when the bands are not engaged. A test drive will indicate if a little more adjustment is needed. This process may have to be repeated a few times before new linings are bedded in.
Hope this helps.
Allan from down under.

[Norman Kling]

Five things can cause a problem:
1. The band is not round and drags in one place even when the pedal is not depressed
2. The lining is not placed correctly. Should hang over the ends about 3/16" at each end and the end rivets placed first. Then the band material is pushed into place and the other rivets placed. That way the lining conforms to the shape of the bands.
3. cam and notch on low band or pedal and cam on reverse or brake are worn so the shaft does not move sideways to tighten the band.
4. Pedal bent so it does not move far enough to tighten the band but is too tight when it is all the way back. Three and four can cause that problem
5. slot in floorboard not cut to allow side movement of pedal.

Also check the drums. If the drums are blue in color, they have been overheating and usually will crack and cause a big bang.
Norm

[TXGOAT2]

The drums need to be round and in reasonable balance and bushings need to be in good condition. I suspect that a "blued" drum may not have the same friction characteristics as one that has not been severely overheated. The surface of the drum needs to be reasonabley smooth. A rough, severely grooved, or out of round drum will cause rapid wear of bands and linkage, and excessively worn parts in the transmission will contribute to further rapid wear of the entire system and generally poor performance.

[George Mills]

Jim,

I take a pretty uniform approach to setting bands...no matter the material, Scandia, Kevlar, or Wood...I'm an equal opportunity user.

First...you really need round band metals...if they were changed through the top hatch chances are they got tugged for convenience and are now an egg...but...moving along for your answer...

I do make them as loose as possible, first time, which really means don't let the pedal bottom out on the floor. ( )

Then I go for a ride on a flat road, start and stop, it won't be right but it tells me where I am at. Then pull the floorboards and cover and adjust a bit more based on what I think is happening. Get the sweet spot balance as near as I can figure with even a 2nd or 3rd run (on Kevlar moreso than other material).

Then I find a hill, any hill as some places I've lived have been mighty flat...and do a start from stop uphill, and a stop from a roll downhill. Take a tweak if and only if necessary.

As to getting the right oil film, I always recommend pumping the breaks on the brake drum...I do so regardless of band material, consider it a critical basic need. "Technically", dumping the clutch on low speed drum to prevent that slip/slide situation. As far as reverse? Pretty much don't tweak. You back up more than 10 feet you take your life in your hands anyway so I usually creep....stop...creep...stop... If you don't, the first time that T goes bonkers in reverse you will wish you had.

[jiminbartow]

When I installed my Guinn wood bands, I installed them with the engine out of the car and the hogshead off and made sure the bands were perfectly round before carefully sliding them onto the drums so, the bands being out of round and causing drag is not a factor in this instance. Jim Patrick

[Art M]

James,
How often or how many miles between band adjustments with your wooden bands. Do they outlast cotton by very much.

Art Mirtes

[jiminbartow]

I have used all types of bands and wood bands are my favorite. If not driven aggressively, or improperly, they will last almost indefinitely, but like all bands, if driven improperly, they can be destroyed in one drive. Mine have been in for 12 years, but admittedly, from 2010 to 2015, I only drove through the quiet neighborhood streets each weekend to the delight of the neighbors and children but since 2015, it has been parked for the last 7 years. I would like to change that and am getting it ready to drive again prior to selling it in order to take potential buyers out for a spin. Jim Patrick

www.mtfca.com/discus/messages/118802/152825.html

[J1MGOLDEN]

The half-way out the slant angle is a must for the reverse pedal.

You will not back up if you can push the reverse pedal to the floor or withing 1 inch eithter.