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Graham Watson
Experienced User
Username: graham508

Post Number: 117
Registered: 03-2016
Posted on Sunday, 11 May, 2025 - 08:01:   Edit PostDelete PostView Post/Check IP

Hello all,
Does anyone know if the current replacement brake shoes on the market today have thicker friction material than the originals? I have recently replaced the brake cylinders, shoes, and hoses on the front brakes of my 48 MKVI and with the adjuster fully out the drum goes from free to stuck as I rotate it. I have checked that the shoes are seated correctly and have adjusted the compensator linkage. Do I need to grind off some of the friction material and/or get the drums turned. Any help would be appreciated.
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Jeff Martin
Frequent User
Username: jeff_r_1

Post Number: 730
Registered: 07-2018
Posted on Sunday, 11 May, 2025 - 09:03:   Edit PostDelete PostView Post/Check IP

When it's stuck, then back off the adjuster until the drum is free, that's where it should be.

The adjuster tip looks like a pyramid, so it will lock eventually and then one turn back for free rotation to the next flat on the end of the adjuster.

Being a 48, are the front brakes the single piston type with the mechanical actuator, or have they been updated to the duel piston type ?

https://www.kda132.com/technical-guide-to-brakes/
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David Hughes
Experienced User
Username: wedcar

Post Number: 180
Registered: 07-2004
Posted on Sunday, 11 May, 2025 - 09:03:   Edit PostDelete PostView Post/Check IP

Graham
The issue is with the linings.
Don't turn the drums unless they are out of true or distorted.
Remove the shoes, with a dial indicator check any run-out of the drums.
Most good brake shops will have the set up to adjust the linings to the diameter of the drums if that is where the issue is.
Regards
David
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Graham Watson
Experienced User
Username: graham508

Post Number: 118
Registered: 03-2016
Posted on Sunday, 11 May, 2025 - 09:11:   Edit PostDelete PostView Post/Check IP

Thanks,
Jeff yes they are the single piston style and the adjuster is backed out as far as it can go. David I will check for run out. Need to find a good brake shop for the other suggestion.
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Graham Watson
Experienced User
Username: graham508

Post Number: 119
Registered: 03-2016
Posted on Tuesday, 13 May, 2025 - 07:17:   Edit PostDelete PostView Post/Check IP

The challenge continues,
I spent a good portion of the day sanding the brake shoes (masks on everyone) to get them to a point where the drum could turn. The way the early brakes are made is that the wheel cylinder is free to slide fore and aft. The return spring pulls the wheel cylinder so that the shoe closest to the front of the car is pushed closest to the wall of the drum. This is where the issue is I think. I sanded a good bit off that shoe but still when I tighten up the drum set screws I cannot turn the drum at all. Does anyone know if there is a difference between early brake shoes and later brake shoes and if so how does one tell which one they have? To check if it was the drum I pulled the one off the other side and tried it, same result.
I have spent way longer than it should take on this, I replaced the shoes in a 51 MKVI and it was just as expected no surprises. I also pulled out the shoe closest to the front of the car and put the drum on, all was fine. I have a new wheel cylinder and it is not attached to the hydraulic line yet so there is no question of residual pressure holding out the piston.
I have gotten some great help on this issue so far, any other suggestions?
Thanks
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NormanGeeson
Unregistered guest
Posted From: 81.98.117.162
Posted on Monday, 12 May, 2025 - 20:38:   Edit PostDelete PostView Post/Check IP

Graham

This seems like a case when the brake shoes have not been centralised to the drum.

Without refreshing myself with the arrangement i would say you need to centralise the shoes by just slackening off the adjuster and the hydraulic cylinder in the back plate, fit the drum then lock up the adjuster followed by resetting the adjuster.

You will find the drum will be a little tight to go over the shoes until the adjuster housing and hydraulic cylinder have centralised by moving in the backplate. The leading shoe lining edges will need just trimming to avoid brake snatching.

(Message approved by david_gore)
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Graham Watson
Experienced User
Username: graham508

Post Number: 120
Registered: 03-2016
Posted on Wednesday, 14 May, 2025 - 10:14:   Edit PostDelete PostView Post/Check IP

Hi Norman,
As usual you hit the nail on the head.
Many thanks
Graham
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David Hughes
Experienced User
Username: wedcar

Post Number: 181
Registered: 07-2004
Posted on Wednesday, 14 May, 2025 - 12:51:   Edit PostDelete PostView Post/Check IP

Graham
Glad that Norman had the answer for you.
Regards
David

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