drum brake newbie questions...

[kshbaja]

I am getting ready to replace the rear drums and shoes on my van. I've never done drum brakes before and had a few questions.

1. I have done a bit of searching and the only special tool I saw mentioned was an L shaped device to manually adjust the shoes after installation. Are there any other tools besides some good needle nose pliers I should invest in to make this job go easier?

2. When I ordered the parts a while ago I went a bit overboard and also got new wheel cylinders. If the current wheel cylinders don't appear to be leaking, is it worth changing them? I know this will require me to open the system and bleed it later.

3. In the aforementioned over zealous order, I also bought a rear wheel bearing kit. I was fresh off the fronts at the time and didn't research the job before buying it. As I read about this procedure today, I am a bit intimidated about getting the axle nuts off and then correctly re-torquing them to 350 ft lbs. I don't detect any obvious problems with the rear bearings, but was thinking of a preemptive measure. Is this a can of worms I don't want to open until I have to?

Thanks in advance.
-kh
_________________
1986 Westfalia

[Phil G]

No special tools required for drum brake and hardware replacement.

Don't use compressed air (dust is unhealthy for the lungs).

Semi-metallic linings add rear braking power. If not using semi-metallics, use OEM linings Ex: Ate (less peddle effort than aftermarket organics).

Clean and lubricate adjusters well before re-installation, and drum locator screws using dry film lubricant or a viscous hi-temp grease (sparingly).

Wheel cylinders are ancient, replacements cheap, and bleeding only take minutes - well worth it, giving you an excuse to change out old fluid via bleeding.

Make sure replacement drums are of good quality.

Make certain hub face is absolutely clean of rust and dirt so new drums seat without uneven stress leading to warpage.

Never use air tools on lugs, especially in the Vanagon rears - use experienced hand or torque wrench only.

You didn't mention miles on the car, but if the rear bearings have no play/noise, leave replacement for later. They won't just suddenly go out on you. Play and then later noise come on slowly over a number of miles. Special tools are cheap and available to make the job of correctly torquing castle nuts an easy deal. Pressing bearings out/in requires special tool when done in the car, or if swing arms are out of the car for bushings anyway, use of a shop press will do the deed with ease. Keep in mind that when the rear bearings do become worn, it is nearly always likely that your CV's will also need at least a proper service if not replacment.

Do not adjust linings too tight initially, and Plan to make a few adjustments over the first 500-1000 miles as the linings seat in.

Oh . . . and have fun!

[HeftySmurf]

Can the drums be painted with caliper paint?
_________________
-Lorenzo
90 GL w/ Bostig

[funagon]

[[email protected]]

one of the usual problems with a vanagon is the drum will rust itself to the hub. So theres good chance that will give you fits. the most stress free way I have found to deal with that is to take the nut off and pull the hub/drum as one unit (like an earlier version bus/bug drum) lay the backside of the drum on the concrete and whack the living shit out of the center of the hub. causing it to break free. clean both the edge of the hub and the drum and put some anti-sieze on both surfaces so it does not happen again. These drums are so thin they don't take any type of prying to well, they warp if you look at them funny with the prybar in your hand

If you don't have large sockets/breaker bars etc.. invest in a "whacker" tool sold by Empi for the nut, you can take the nut on/off with it and a big hammer and get in the proper torque range. Works fairly decent if you have stock steel wheels, just leave the wheel on and on the ground to loosen and final tighten of the nut-do not forget the cotter pin! Its also wayt easer to redo the brakes with the hub out of the way

I also suggest doing the wheel cylinders as well along with a good flushing of the brake fluid, might even want to go a step further and do the flex lines, gets more involved, but for the cheap the cost of fluid and the parts, its well worth it considering the age of the vehicle.
_________________
Markus

[Phil G]

Sure, drums can be painted, but most coatings degrade the part's ability to shed heat. There are heat dissipative coatings of course, but colors are limited. Generally, many road vehicle's rear drum brakes are never taxed in ways that would matter whether the drum was painted or not. On the Vanagons though - particularly early campers, the mass of the drum and swept area in the rears are really at their minimum for the job they must do, so I personally would never do anything that could degrade their performance or longevity. In contrast, if you had an old 3/4 ton Chevy pickup you never tow 10,000# trailers with, you could slap cheap house paint 1/2" thick on the rear drums and it wouldn't matter. The drums still never get hot enough to be a problem for themselves or any coatings that happen to be on them.

For what it's worth, here's a Vanagon rear brake story for you:

When I purchase a brand new Vanagon L in 1981 I discovered it had a rear brake problem in the first few thousand miles. When braked hard from speed, the van wanted to get sideways - great for pucker factor, not so good for my own longevity. Since it was a warranteed new car I took the van into the dealer . . . a number of times, and the problem just got worse with peddle pulses indicating warpage. Finally, after notifying VW North America they were getting hosed by the dealer who was charging them for each visit - without the car getting fixed, VW-NA sent a very German looking 'cleaner' out to meet me with the car at the dealership. After a few hot laps in the dealer's neighborhood the rep - pointed grey shoes and all, began grumbling in German then said they had a solution that would take 1 day. He then made the dealer remove the entire 'rear' from the car. The engine, trans, and complete rear suspension were swapped out for a set out of another new car used as a donor. The wheel lugs still had the factory inspection paint mark indicating the wheel's connection to the suspension had not been disturbed. I was then asked to not use the parking brake after the brakes had got warm (around town driving) until they could confirm the problem and solution. This was weird . . a new car with manual transmission and I couldn't use the parking brake . . if I had lived in a hilly area I would have had to carry around a hunk of wood for a wheelstop!
In the end, after VW's tech center had thoroughly inspected my car's removed components and investigated the repair history the following facts came to light:
1. Original problem was caused by tight initial adjustment during break-in.
2. Drums on future vans required redesign to make them less sensitive to warping when warm, then allowed to cool with the parking brake applied.
3. Dealer had been ruining each new set of drums they installed by the use of air tools on the lugs in contravention of a memo circulated months before, indicating this may be the source of many warrantee complaints.

Since I was a Mercedes mechanic at the time and enjoyed taking 'German shop', old Wolfgang Ruhl with the pointed grey shoes took a liking to me and kept me in the loop. I in turn, kept him up to date for about a year.
I never had trouble with their 'final solution' of just replacing everything in the rear of the car with untampered components, but they gave me a set of the re-designed drums when available that I later installed. Mr. Ruhl confided that he was not particularly pleased with the re-deign, saying they were still too lightly constructed and too sensitive to problems that would inevitably result when untrained US brake shops got their hands on them. So you can see where I get some of my ideas about the Vanagon rear drum brakes - straight from the goose-steppers mouth

[Phil G]

In reference to drum seizing on hub mentioned above, this is a more serious issue in areas where salts/clorides are used on winter roadways. Otherwise, simply heat the center of the drum with a torch, give the center 'seam' a squirt of PB blaster, wait 10-15 minutes, then give the cooled drum a whack and off it will come. Since you should alway replace Vanagon drums with new ones, warping the old drums with torch heat is of no concern.

P

[HeftySmurf]

Hey Phil,
I think i F'd up... I painted the insides of the drums w/ POR15? Is that going to be a problem?
_________________
-Lorenzo
90 GL w/ Bostig

[greenbus pilot]

[MsTaboo]

[HeftySmurf]

No dude, I'm serious.....
_________________
-Lorenzo
90 GL w/ Bostig

[Phil G]

mike_z :

In theory you could have problems, but since I have never personally painted the insides of a set of brake drums to know, I just honestly can't say you will my friend.

Of course . . I can say with certainty there is one way to find out
. . . and another way to avoid finding out

P

[MsTaboo]

Mike-Z

OK I'll rise to this again...some more info please. when you say you painted the insides of the drums do you mean ALL of the insides? Or just the inside face where the drum contacts the hub?
If you painted the contact surface (where brake shoes meet drum) then I think you will have serious trouble.
If you just painted the inner face then maybe not. However, I have used POR 15 extensivly on a 71 bay restoration, and the stuff is very thick and sort of gooy. I'm not sure how it will react with heat (and your drums get quite hot!) It may act like a glue, and weld your drums to the hubs, making removal even more difficult. At very least, the surface may be uneven, leading to warping.
If you indeed painted the contact surface, then you will need new brake shoes very soon!

Hope you were just joking If not, get out the razor blades and good luck!
_________________
Currently:
'90 Syncro Westy 3 knob w/Zetec

The information age has morphed into the age of disinformation and willful ignorance. Agnotology!
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[HeftySmurf]

Doah! Well im just gonna get some new ones then... Chaulk it up on the retard log
_________________
-Lorenzo
90 GL w/ Bostig

[Phil G]

I didn't even consider the possibility of the friction surfaces getting a paint job. .

"Hey Harry, did you change your shorts today?" "Yes Edna, thats only the rear brakes on fire . . . . hey, are there any of those weenees left? . . ."

[Dogpilot]

Don't feel bad, you will not regret the purchase of new drums. The brakes will work oh-so-much better. The adjuster seem to be less able to cope, the further they have to adjust. A small secret when you install the drums; adjust the adjusters out so it is loose enough to install the drums. put the drum on and pump the brake at least 3 times. Check and see if the drum turns smoothly. If it still turns smoothly , take it off, adjust it out a few clicks and repeat the process. Do this until the shoes are starting to rub on the inside of the drum. Then back it off a couple of clicks, until it turns smoothly.

The proper way to do it is to measure the inside of the drum and adjust the shoes to a couple of mm to that measurement. It unfortunately requires the use of gigantic cartoon calipers to do the measurement, and Roger Rabbit still has my set.
_________________
Geology with a Syncro rocks!
86 Syncro Westy AKA "The Bughunter"
98 Disco I
08 Range Rover SC
08 VW Rabbit S
1951 O-1G

[HeftySmurf]

I had them turn and they are good to go, the were actually a little out of wack......
_________________
-Lorenzo
90 GL w/ Bostig

[ZimmerVan]

So I'm in the process of replacing my shoes/drums...

As I thought it would be, the drum (passenger rear) is rusted to the hub, currently soaking in PB Blaster, getting the torch tomorrow.

E brake is off and loosened, but for the life of me I can't figure out the star adjuster in the drum/backing plate. The drum rotates pretty freely but I think I need to back the shoes off completely. How is this done via the star adjuster??

Right rear drum if that helps

[ZimmerVan]

OK, I'll answer my own question:

The star adjuster was rusted to the threads of the spreader, that's why I couldn't figure it out! PB+torch loosened that right up. I finally figured this out after I got the drum off.

I MAP torched and PB blastered the bejeezus out of the drum. It would not release with prying or moderate pounding. When I finally grew a pair, put in the eaplugs, and wailed away with the sledge the drum released!!!

Then I broke one of the return springs while removing it. Had to run and get a new hardware set, luckily in stock at my FLAPS.

All in all I replaced drums, shoes, wheel cylinders and shoe hardware and bled the brakes. Oh yeah, didn't forget the anti-seize as my ounce of prevention from having to use the "shock and awe" campaign on the drums again!

This was by far my longest (and most successful) day under the ZimmerVan.

Whew......it......is......Miller time.......

[Captain Pike]