TT Emergency/Parking Brakes

[mtntee20]

With the mass of knowledge on this forum, I'm sure someone has an answer for me.

Our TT did not have brake shoes in the drums when we purchased it. Thanks to Tom Strickling, I have brake shoes. I put new linings on 2 pair and installed them. When I went to put the driver's side wheel back on, it would NOT fit past the brake shoes. I had backed off the Benet brake bands so they would not hinder the removal or installation.

I doing some research on this forum, I found out I had the links connected to the actuator cam wrong. I had the top shoe link forward and the bottom shoe link to the rear. A photo from this forum clearly showed the top shoe link to the REAR and the bottom shoe link to the FRONT. I reversed the links and the wheel went on just fine.

I checked my work on the passenger side and found the links opposite of what I had just installed on the driver's side. I reversed the linkage on the passenger's side. I purchased new brake rods as they were missing. I found the rods are too long as manufactured. I shortened and re-threaded the driver's side rod and it fits well and appears to be operating properly. I moved it to the passenger's side to verify configuration prior to cutting and threading the second brake rod.

While I can adjust it to fit, the brake shoes will NOT allow the Brake handle/lever move from all the way forward (high) backward to neutral/low. The brake shoes set up tight before I get to neutral.

My Question: Are the shoe linkages, connecting the the actuator cam, the same orientation on BOTH sides OR are they exactly OPPOSITE?

From what I have experienced, I am expecting to hear they are supposed to be opposite (a mirror image of each other). I have been unable to find a photo of the passenger side brake linkage. I would like to have some input before I pull the passenger side wheel off again.

Thank You All in Advance. I sincerely appreciate you help.

Cheers,
Terry

[StevenS]

Terry,

The brakes set up would be the same on both sides (a mirror image of each other). The best way I can describe it. If you were sitting under the truck, in front of the rear end, looking out the back of the truck, and you turned your head right to the driver's side and then turned your head left to the passenger's side, the brake set up of all the parts would look the same. If all set up perfect, the angles on the lever arm and cams would also be the same. Hope this helps.

[Scott_Conger]

The linings are in all likelihood a little too thick, and the rods are likely still too long which will keep the brake handle from going fully forward.

I suspect that if you set your handbrake to JUST where the brake handle cam puts the transmission in neutral (in all likelihood a little forward of vertical) you will be able to both adjust the rods shorter and also have neutral and immediately after that, set brakes.

[mtntee20]

Steven, Thank you, that's what I am thinking. The photo showed the top shoe link angled towards the rear of the truck connected to the top of the brake cam. The bottom shoe link angled toward the front of the truck connected to the bottom of the brake cam.

I had a 50/50 chance of getting it correct and blew it.

Scott, When I "measured" the brake rod, I had the brake lever all the way forward so as the truck would be in HIGH gear and the brake actuator pushed all the way to the rear as to be released. I then put the brake rod up and marked where I wanted to cut it off ( about 2 1/2" worth) and how far I would have to thread farther down the rod. When I was where I thought I should be, I test fit it. The length was good and the brake handle appears to operate properly both for the transmission and the emergency/parking brake but there were not enough threads for a lock nut and future adjustment. I took it off and added threads.

I re-installed and tested: Worked good. Took it off and moved to the other side and NO WORKEE. The parking brake locks up way to early. I still have plenty of throw on the actuator arm so I know it's not bottoming on that. The only answer is inside the drum that I can see.

Looks like I'm going to have to pull that wheel and see how much throw is actually inside the drum. Maybe try to reverse the upper and lower links, replace the wheel and see how much throw I have then.

Gentlemen, Thank You for your input. I understand what you have said and how it may apply to my thinking and brakes. I'll be sure to post what I find out. As you suggested, I may have to reduce the lining thickness. Good thing I countersunk those rivet heads as I was supposed to.

Terry

[A Whiteman]

Well, a picture is worth a thousand words. The position of the cam and links is about per this picture. Left and right are the same - i.e. the cam 'leans back' on both sides, and top link angles back as well. When the rod pulls forward it pulls the cam and expands the shoes.
(the grey painted seal carrier is home made - works fine )

The lever should be vertical like this: The teeth at the end of the lever allows some adjustment (see Martynn's diagram): https://mtfca.com/phpBB3/app.php/gallery/album/59

YOU MAY BE ABLE to adjust the lever so it 'leans back' a little if your rods are a little too long. Don't lean it back too much or you lose leverage.

1918-1927ModelTTRearBrakeAssembly-1-C.jpg (39.66 KiB) Viewed 1795 times

[mtntee20]

Adrian,

If that is YOUR photo, THANK YOU for posting it. I used that exact photo to remedy my problems on the driver's side and check the passenger's side, which I had backwards as well. That leaves just one alternative: Pull the right side wheel, remove the shoes, and grind down the lining a bit.

I have both actuating levers straight up. The throw on the left is more than it is on the right. With all of your help, I believe I am on the right track to successfully install operating parking brakes on this old girl.

THANK EVERYONE WHO HAS POSTED HERE.

Terry

[Scott_Conger]

Terry

"straight up" bellcrank should be when the brakes are fully engaged, and when released, the bellcrank should be laying backwards

[Mark Gregush]

If the shoes are not draging, why not just take the levers off and re clock them?

[mtntee20]

Scott,

Thank you for the information.

Mark,

The total travel from full released to full engaged is about 1/2" or so on the left and 1/4" on the right. Seems to be adequate on the left but definitely NOT enough on the right. I set the linkage at Brake handle fully forward (in high gear) and the brakes fully released. With the right side connected, the brake lever stops before reaching neutral.

I will pull the right wheel and ensure all is properly installed. IF it is, then I will have to remove some lining. I will also readjust the levers to lean back when fully released and be approximately vertical when fully engaged.

Thank You both for your input.

Terry

[A Whiteman]

and grind down the lining a bit

Yes, I had to do the same on one side too (the linings used by the brake shop were a bit thick)

And yes, it is one of my photos. Just drop a message if I can help with other pics.

Lever up or back - just so that it is not forward, in such case you lose leverage. Mine are leaning back a bit when 'off'.

You may have to adjust the lever as the shoes wear (hence the toothed design).

[mtntee20]

Gentlemen,

I figured out the problem. The links between the shoes and the cam are stamped/cut steel. Even with the corners clipped off, the link hits inside the cam, during rotation, and will not allow full release.

I thought, at first, the upper shoe was hitting the spring perch nut but it wasn't. Thus, I had to look farther. Moving the actuator lever, it would hit a hard stop in one direction and hit the radius rod in the other. Finally found the spot. I ground the ends of the links round, just taking off the points of the 45 degree angle cuts. Reassembled and everything works great now. Take a close look at Adrian's photo, specifically, the connecting links: They have round ends.

Keep in mind, the top shoe now sits down on the perch nut limiting the release amount. There is plenty of release distance in this configuration. No brake drag noise.

NEXT problem: Now I have to do the same to the opposite side. When I get to that, I will get some photos to show. Then, the future generations will have some photos to look at.

Thank you all once Again!

Terry

[Scott_Conger]

Repro parts strike again!

good job sorting that out

[mtntee20]

As Promised:

First photo: Brake links AFTER being ground round on the ends.
Second photo: Brake links as supplied with the cut ends.
Third photo: After ground and installed. NOTE: You will be able to see the top shoe sitting down on the spring perch nut. This is as far open and it will ever go without modifying the perch nut.

I hope this will help someone in the future. I know some of you will remember and pass this info on. Thank you for doing so and you have my full permission.

Good Luck,
Terry

[A Whiteman]

"Two Thumbs Up"