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Mon Aug 07, 2023 7:50 am

Hi everyone, I have replaced the rear brakes (Drums, Shoes, hardware, wheel cylinder and rubber brake lines, backing plates, and new bearings on both sides)

My issue is the passenger side keeps warming up. The new bearings have made the issue lessen slightly. The Shoes are backed off and not adjusted out fully (can remove drum easily). New backing plates rub when I corner or just after i release the brakes. Any advice or questions please let know, Thanks

Yesterday I drove 120 miles, fine on the highway, starts to heat up in town around corners. 180 F is the hottest temperature I saw with my laser thermometer. Drivers side never over 110-120 F

Mon Aug 07, 2023 8:18 am

Don't know about the rubbing but the photo shows a spring missing.

Mark

Mon Aug 07, 2023 8:45 am

https://www.thesamba.com/vw/gallery/pix/1781118.jpg

Mon Aug 07, 2023 9:05 am

crazyvwvanman wrote: Don't know about the rubbing but the photo shows a spring missing.

Mark

Thanks Mark, I did install the missing spring for the adjuster locking thingy

Mon Aug 07, 2023 11:00 am

Shoes do not look positioned the same front to rear.

Two things make a brake drum rub. Either the base adjustment is not correct or the hydraulics are holding pressure. How old are the flex hoses? They will swell up internally blocking the release of pressure.

That spring is part of the self adjusting mechanism. I usually run the adjuster out as far as I can and still get the drum on. Drive it and then readjust through the hole in the backing plate.

Mon Aug 07, 2023 11:32 am

MarkWard wrote: Shoes do not look positioned the same front to rear.

Two things make a brake drum rub. Either the base adjustment is not correct or the hydraulics are holding pressure. How old are the flex hoses? They will swell up internally blocking the release of pressure.

That spring is part of the self adjusting mechanism. I usually run the adjuster out as far as I can and still get the drum on. Drive it and then readjust through the hole in the backing plate.

Flex lines are new, I had the same thought. The front shoe seems to have upward pressure, holding the top of the shoe against the drum. The rest of the shoe retracts. Have you heard of grinding the shoe before? Thanks for the reply

Mon Aug 07, 2023 11:58 am

Back in the day, our brake lathe had a grinder for fitting new shoes. The asbestos thing took that out of the shop arsenal.

In theory you could get some 40 or 80 grit air file strip sandpaper that is self adhesive. Stick it to the drum and sand away to improve the contact patch.

Mon Aug 07, 2023 1:37 pm

twosmallguyswithbighair wrote:
..... The front shoe seems to have upward pressure, holding the top of the shoe against the drum. The rest of the shoe retracts. ....

I doubt it's a factor in front shoe position and I could be wrong on this method but ...

Did you apply *judicious* amounts of brake lube to points on backing plate where shoes contact and where shoes contact wheel cylinder, lower "anchors" ?

To help rule out a sticky e-brake cable....

After assembly, ensure each wheel turns properly. During re test, don't use e-brake, see if issue persists.

Neil.

Mon Aug 07, 2023 2:05 pm

twosmallguyswithbighair wrote: New backing plates rub when I corner or just after i release the brakes.

that doesnt sound right - something is loose allowing the drums to move relative to the backing plate in the wrong axis...

do they get hot even if the adjusters are backed out super loose?

it seems like maybe theres something going on here beyond just brake adjustment or dragging brakes

Mon Aug 07, 2023 6:19 pm

Thanks for the reply's, I will apply lube carefully tomorrow and back the adjuster off a ton and see if it gets better.

Mon Aug 07, 2023 7:04 pm

I would assemble everything with proper torque, jack up the rear tire, and grab the top and bottom of the tire to simulate cornering. Does it wiggle?

Roland

Mon Aug 07, 2023 8:44 pm

RolandD wrote: I would assemble everything with proper torque, jack up the rear tire, and grab the top and bottom of the tire to simulate cornering. Does it wiggle?

Roland
Torqued the axle nut then tightened slightly to apply cotter key.

There was play before I replaced the bearings. Now with the new bearings, there’s no play anymore. Notably, the passenger side(side with issues) stub axle went into the new bearings with less effort than the drivers side. No noticeable wear on the stub on either side

Tue Aug 08, 2023 4:30 am

Each shoe contacts the backing plate at 3 raised spots. They should get a film of grease. They help the shoes slide. I missed that you had the stub axles out. I always do rear brakes with the hubs in place. You have added another place to look.

Also, it’s hard to tell, but I think the bracket on the rear shoe should have the long side out. If I’m wrong, someone will correct me. Memory not as clear as I’d prefer.

Tue Aug 08, 2023 9:28 am

valvecovergasket wrote:
that doesnt sound right - something is loose allowing the drums to move relative to the backing plate in the wrong axis...

I agree but scratching my head as to what exactly is the cause? It is lessening as a drive more :?

valvecovergasket wrote:

do they get hot even if the adjusters are backed out super loose?

I tried this and both drums stayed the same temp over 10 miles so I’d say no they don’t get hot with the adjuster backed off. I do have some pedal pulsing can a outa round drum do this?

Tue Aug 08, 2023 9:33 am

Quote: I do have some pedal pulsing can a outa round drum do this?

Yes they can. I've seen new drums out of round, that needed to be put on a brakelathe with the drive hub and lugs torqued to spec.

Might verify the new drums are seated properly. Derust the hub where the drum seats and get the drum retaining bolts in. Torque the wheel lugs and road test.

Hard to measure the inside of the drum for out of round.

Edit: Found this picture from member crazyvwvanman. Notice the bracket is well beyond the rivet.

Tue Aug 08, 2023 9:38 am

MarkWard wrote: Each shoe contacts the backing plate at 3 raised spots. They should get a film of grease. They help the shoes slide. I missed that you had the stub axles out. I always do rear brakes with the hubs in place. You have added another place to look.

Also, it’s hard to tell, but I think the bracket on the rear shoe should have the long side out. If I’m wrong, someone will correct me. Memory not as clear as I’d prefer.

Last summer I did the brakes, drums and 1 wheel cylinder. This summer I replaced the other wheel cylinder on the passenger/issue side to match the new one on the drivers all with the hubs in place. Then I started having problems, lots of play in the bearings so that happened next also with the new backing plates. Can you elaborate about which bracket you mean?

Tue Aug 08, 2023 9:44 am

MarkWard wrote:
Might verify the new drums are seated properly. Derust the hub where the drum seats and get the drum retaining bolts in. Torque the wheel lugs and road test.

Hard to measure the inside of the drum for out of round.

Thanks Mark, I tried to find someone/place with a brake lathe without any success, so I’m getting another drum I guess. I will check and clean the hub before I do that though.

Tue Aug 08, 2023 10:03 am

It does seem to be in a different spot than the picture you posted but is in the slot… Brake shoe incorrectly made maybe. Doh!

Tue Aug 08, 2023 10:25 am

Bracket is flipped where it contacts the shoe. Easy to correct. It’s possible if you got the new drum hot, that could have warped it. Brakes have a specific method for bedding in.

Tue Aug 08, 2023 10:34 am

The long side of the adjuster rod fork goes in, like the photo just above.
It is intended to constantly ride in the slot in the shoe and the long tip to normally be bottomed out in that slot in the shoe.
Being bottomed out is the only way that the adjuster rod can directly expand the shoes as the rod adjusts longer.

That is until the parking brake handle is pulled as then it rides part way out of the slot as the shoes spread.
When the handle is released it should again bottom out in the slot of the shoe.

EDIT: The photo of mine further above with the yellow arrows is pointing out MISTAKES with the arrows, not showing how it should be.

Mark