Parking brake rods are too short

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Reno Speedster
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Parking brake rods are too short

Post by Reno Speedster » Fri May 12, 2023 3:35 pm

I did a parking brake rebuild on the 22 which included installing new cams and brake shoes. The arms on the cams appear to be in the right position but now the rods won’t connect to the arms on the handbrake lever when it’s all the way down unless the cams are partially rotated. Is this an adjustment issue or have I done something wrong?
Attachments
The position of the cam arm.
The position of the cam arm.


Norman Kling
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Re: Parking brake rods are too short

Post by Norman Kling » Fri May 12, 2023 4:15 pm

That bend in the rod doesn't look correct. The rods should have an offset to get around the radius rods but I haven't seen one with a curve like that. Anyway, adjust the rods to where the pin just goes through the clevis with the parking lever all the way forward and the arm on the backing plate all the way back. Then check that both brakes get tight at the same point when you pull back the lever. Final test would be that you can shift from low to high with the pedal without needing to push the parking brake lever forward and that the transmission is in neutral with the lever straight up. Also if you drive on level smooth concrete and pull the parking brake lever the car does not pull to one side.
Norm


Scott_Conger
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Re: Parking brake rods are too short

Post by Scott_Conger » Fri May 12, 2023 5:42 pm

for starters, rod should look like this as mounted...does it?
546011.jpg
546011.jpg (47.2 KiB) Viewed 1280 times
Scott Conger

Tyranny under the guise of law is still Tyranny

NH Full Flow Float Valves™
Obsolete carburetor parts manufactured


Topic author
Reno Speedster
Posts: 573
Joined: Tue May 26, 2020 6:23 pm
First Name: Morgan
Last Name: Blanchard
* REQUIRED* Type and Year of Model Ts owned: 1926 Model T Speedster Project, 1922 Runabout Pickup
Location: Anchorage, Alaska

Re: Parking brake rods are too short

Post by Reno Speedster » Fri May 12, 2023 9:08 pm

That’s what the rod looks like and the position is correct. It’s hard to tell from that shot if the cam arms are in the right place.


Scott_Conger
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Re: Parking brake rods are too short

Post by Scott_Conger » Fri May 12, 2023 9:20 pm

when at rest, or the brake "off", the arm should cant back like it is (yours looks a little far back but perhaps the brake shoes aren't on?)

the cams come as "left" and "right" and if mixed up, the lever will be forward when the cam is at rest, so I'd say you have everything assembled correctly
Scott Conger

Tyranny under the guise of law is still Tyranny

NH Full Flow Float Valves™
Obsolete carburetor parts manufactured


Topic author
Reno Speedster
Posts: 573
Joined: Tue May 26, 2020 6:23 pm
First Name: Morgan
Last Name: Blanchard
* REQUIRED* Type and Year of Model Ts owned: 1926 Model T Speedster Project, 1922 Runabout Pickup
Location: Anchorage, Alaska

Re: Parking brake rods are too short

Post by Reno Speedster » Fri May 12, 2023 9:47 pm

The shoes are in and that is with the cams at level. Everything is new so I will need to adjust things. The pins for mounting the arms on the cams are smaller than the holes, so I am going to machine and install some custom pins tomorrow.

Part of the problem was that about half the threads in the two brake clevis were stripped. I got some new ones from the industrial hardware in town and they are about 1/2 longer than the originals, which helped. Now I can at least get the rod into both clevis with the parking valve all the way forward.


Norman Kling
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Location: Alpine California

Re: Parking brake rods are too short

Post by Norman Kling » Fri May 12, 2023 9:55 pm

looking at the picture posted by Scott, the rods look right. Try adjusting as I posted. I think it will work unless the threads have been stripped or someone sawed off the rods.
Norm


Swinz
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Re: Parking brake rods are too short

Post by Swinz » Sat May 13, 2023 12:43 pm

This guy had a similar issue to you and describes his solution to the problem.
https://youtu.be/qe6qY-YfjYw


Scott_Conger
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Re: Parking brake rods are too short

Post by Scott_Conger » Sat May 13, 2023 2:34 pm

yes, he did, but his solution now relies on the brake shoe return springs (alone) to not only collapse the shoes but additionally now must drive the actuator cam to "zero" since the brake rods will no longer do it. Any bind or friction along the rod will likely overwhelm those wimpy springs and keep the shoes constantly dragging. If he had simply made his long clevis with just a hole as original, it would have been far better and the system would still work as designed. A+ for creativity, but C- for not understanding the design or function of all part of the system.

This sliding clevis works fine for external brakes which are of a totally different design and are tolerant of it.

It's not a solution I'd use or recommend...if the rods have some stripped threads as Morgan has stated, then he can replace the rods, lengthen the rods' threads, or make extra-long clevis' to work with the too-short rods. Just don't slot the clevis.

From his post, he has overcome the stripped threads by purchasing extra-long clevis'. Done.
Scott Conger

Tyranny under the guise of law is still Tyranny

NH Full Flow Float Valves™
Obsolete carburetor parts manufactured

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