79 Bus Brakes Dragging

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airkooledchris
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79 Bus Brakes Dragging

Post by airkooledchris » Thu Jan 20, 2011 10:09 am

Amskeptic wrote: Find a dead-level bit of asphalt. Set the car rolling with a good push at the driver's door pillar. Does the car slow to a stop imperceptably, or do you feel it stop? Repeat in reverse. Report back.
Colin
I can feel it grab/stop going forward... not AS noticeable in reverse, but I think I can feel it sorta grab and stop at the end of the roll in reverse as well.

ive felt that a little at stoplights sometimes, where I can let off the brake and it'll hold it's position without rolling forward/back like you'd expect it to with a perfectly smooth free wheeling setup.
not all the time, but sometimes it is very noticeable when it grabs and holds it's position at a stop.

I never smell brakes like they are hot, but maybe they are grabbing or dragging just enough?
1979 California Transporter

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dtrumbo
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Re: 79 CA bus - poor fuel economy

Post by dtrumbo » Thu Jan 20, 2011 1:39 pm

airkooledchris wrote:I never smell brakes like they are hot, but maybe they are grabbing or dragging just enough?
I had this happen to me on my '78. It turned out the parking brake cables were sticking slightly in their tubes resulting in the parking brakes not releasing completely. I replaced the cables which by definition means the old sticky lubricant on the old cables was replaced as well and my problem went away.
- Dick

1970 Transporter. 2015cc, dual Weber IDF 40's
1978 Riviera Camper. Bone stock GE 2.0L F.I.
1979 Super Beetle convertible.

... as it turns out, it was the coil!

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Amskeptic
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Re: 79 CA bus - poor fuel economy

Post by Amskeptic » Thu Jan 20, 2011 7:17 pm

airkooledchris wrote:
Amskeptic wrote: Find a dead-level bit of asphalt. Set the car rolling with a good push at the driver's door pillar. Does the car slow to a stop imperceptably, or do you feel it stop? Repeat in reverse. Report back.
Colin
I can feel it grab/stop going forward... not AS noticeable in reverse, but I think I can feel it sorta grab and stop at the end of the roll in reverse as well.

ive felt that a little at stoplights sometimes, where I can let off the brake and it'll hold it's position without rolling forward/back like you'd expect it to with a perfectly smooth free wheeling setup.
not all the time, but sometimes it is very noticeable when it grabs and holds it's position at a stop.

I never smell brakes like they are hot, but maybe they are grabbing or dragging just enough?
Take that information into consideration for your lousy fuel economy. Next investigation would include jacking up each wheel and checking for drag immediately after pressing the brake pedal firmly + add an application of the emergency brake for each rear wheel test. Those spark plugs are almost begging that you not lean the mixture any further.
Colin
BobD - 78 Bus . . . 112,730 miles
Chloe - 70 bus . . . 217,593 miles
Naranja - 77 Westy . . . 142,970 miles
Pluck - 1973 Squareback . . . . . . 55,600 miles
Alexus - 91 Lexus LS400 . . . 96,675 miles

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airkooledchris
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Re: 79 CA bus - poor fuel economy

Post by airkooledchris » Thu Jan 20, 2011 10:57 pm

so, to answer the question "which brakes are dragging, the front or rear?"

YES.
http://youtu.be/tttUjdVjFNA

I can barely spin the front wheel at all, and the rear is definitely grabbing at least a little. It's dark and cold so im not going to try adjusting the rear right now, but the metal tube that houses the drivers side e-brake cable is slightly crushed and the drivers side shoes in the rear are at least 50% more worn down that the rear passenger side shoes. I haven't had the bus long enough to know that the rears were last done at the same time, but it's at least a concern.

Im not familiar with what a sticking front brake means (new caliper, or adjustment of some sort?)
1979 California Transporter

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airkooledchris
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Re: 79 CA bus - poor fuel economy

Post by airkooledchris » Thu Jan 20, 2011 11:34 pm

Amskeptic wrote: Unstick caliper, replace brake hose, replace caliper.
not questioning the advice, just my understanding - replace brake hose and caliper as in replace with new parts, not removing and reassembling correct?


thanks again. I sense an end to my tail chasing... :salute:
1979 California Transporter

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Sluggo
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Re: 79 CA bus - poor fuel economy

Post by Sluggo » Fri Jan 21, 2011 10:11 am

I think he means pull the cylinder & unstick it. The replace the hose with new and reinstall the OG cylinder.
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dingo
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Re: 79 CA bus - poor fuel economy

Post by dingo » Fri Jan 21, 2011 10:05 pm

after a run you can feel the heat of the rim(s) that is culprit dragger. once you have freed caliper and pushed piston back in, try it out...if the scenario repeats then the piston is jamming up on rim of rust, and replacement caliper required. its possible that decayed hoses could be the source of issue, but at the salty coast, ill guess scenario a)
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';78 Tranzporter 2L

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airkooledchris
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Re: 79 CA bus - poor fuel economy

Post by airkooledchris » Sat Jan 22, 2011 2:20 pm

Image

Image

Image

Image



No backing plates are present, dust boots inside caliper are totally shot, the disc is very rusty everywhere but where the pads touch it.

Should I just have the original calipers rebuilt, and get new hardware and disc? (along with new pads, rubber hose and backing plates?)

Im guessing if I do all of this to the drivers side, I need to do the same on the passenger side? The drivers side was sticking all the time, but the passenger side spins freely.
1979 California Transporter

vdubyah73
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79 CA bus - poor fuel economy

Post by vdubyah73 » Sat Jan 22, 2011 2:44 pm

If you have a caliper rebuilder near you, it will be cheaper than buying rebuilt from anywhere else. same goes for starters, alternators and generators. We used to have a brake and caliper shop around here, I sure do miss it. We do have an auto electric rebuilder, and their cost is less than half what it would cost to buy the same thing. Plus they will inform you on how many rebuilds you have left in whatever part you have them do.
1/20/2013 end of an error
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Amskeptic
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Re: 79 CA bus - poor fuel economy

Post by Amskeptic » Mon Jan 24, 2011 10:18 pm

airkooledchris wrote:
Amskeptic wrote: Unstick caliper, replace brake hose, replace caliper.
not questioning the advice, just my understanding - replace brake hose and caliper as in replace with new parts, not removing and reassembling correct?


thanks again. I sense an end to my tail chasing... :salute:
Sorry I was in shorthand mode, those are a sequence.

First, unstick a frozen caliper if you can . . .
Second, if it wasn't frozen in the first place, replace brake hose . . .
Third, if the caliper remained frozen, replace caliper . . . or sumpin.
Colin
BobD - 78 Bus . . . 112,730 miles
Chloe - 70 bus . . . 217,593 miles
Naranja - 77 Westy . . . 142,970 miles
Pluck - 1973 Squareback . . . . . . 55,600 miles
Alexus - 91 Lexus LS400 . . . 96,675 miles

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Manfred
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Re: 79 Bus Brakes Dragging

Post by Manfred » Thu Jan 27, 2011 10:01 am

One of the first things I did to my bus was to completely go through the entire brake system. It saved my life. I found out both my front calipers were frozen and one rear wheel cylinder was not working. The entire bus was being stopped with one rear drum brake and the brake pressure felt great.

What I did:
Installed new rotors
Installed new wheel cylinders
installed new brake pads/shoes
installed new drum hardware
completely flushed the entire brake system..the fluid was black!
Cleaned and greased all parking brake hardware and adjusted the parking brake

After the flush my calipers started working again and she brakes better than any thing I've ever owned

I got everything from Bus Depot...great quality and prices are low.

Remember that the engine pressure provides brake boost. If your fluid is old and dirty or you have air in your lines, your engine isn't getting enough pressure/vacuum.

Ratwell has a great right up for brakes. But I think all his pics are down.
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airkooledchris
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Re: 79 Bus Brakes Dragging

Post by airkooledchris » Mon Jan 31, 2011 3:47 pm

What I did:

NOS VW calipers
NOS Sebro disc's
New front brake hoses
flushed old fluid, replaced with ATE Super Blue
New brake pads
New brake pad backing plates

The hardware I had purchased, those pins and springs for the calipers, wasn't here yet so I re-used my old ones after cleaning them up a bunch.
I may still swap in the new hardware in a few days time, as those little bolts that hold the discs to the hub are all stripped and I need to replace them anyway (those won't be here for another week or so.)

The process went relatively smoothly. Turning the caliper pistons into the correct position for the backing plate tabs was a bit of a pain in the ass. I don't have any special tools to do this so I had to tap tap tap with a deadblow hammer and screwdriver until it turned into place. Maybe they are easier to turn when rebuilt recently Vs sitting on the shelf for years, but I got them into place eventually and installed.

I used a Motive power bleeder, borrowed from a friend, after ordering an adapter for the VW reservoir cap. If your not sure that thing is worth the $$, it is. I assumed since I never used one before id have to bleed a few times to get it right - wrong. One and done. Using the Super Blue fluid from ATE really helped to, as once you see blue you know the old fluid is gone and you can move on to the next wheel.

I picked up the hoses, calipers and rotors from Gary Ploof out of Beaverton Oregon.
He has a small stockpile of old NOS VW parts and you can view his offerings here: http://www.thesamba.com/vw/classifieds/ ... =vwman6559
Great communication, quick shipping, and good prices on his parts. He sent me brake hoses instead of the hardware, then sent the hardware out the very next day and said I could keep the hoses.
As a plus, the box with my calipers in it had a few vintage VW tools I wasn't expecting. (the stock spark plug tool w/bar, with the little rubber insert still in place.)


here I am lining up the backing plates with the caliper piston:
Image


the pattern on NOS disc's:
Image
1979 California Transporter

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Manfred
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Re: 79 Bus Brakes Dragging

Post by Manfred » Fri Feb 04, 2011 10:01 am

airkooledchris wrote:What I did:
flushed old fluid, replaced with ATE Super Blue
Are you racing? :geek: I guess you won't worry about your fluid boiling coming down a mountain.

Sweet! You are going love those brakes now. Did you rebuild your rear drums?
1978 Westy FI
hambone wrote:Some times ya gotta wing it.

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chitwnvw
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Re: 79 Bus Brakes Dragging

Post by chitwnvw » Fri Feb 04, 2011 10:43 am

Where'd you get new backing plates? That same guy on Samba? Sorry I am too lazy to browse through his 14 pages of parts... 8-[

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airkooledchris
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Re: 79 Bus Brakes Dragging

Post by airkooledchris » Fri Feb 04, 2011 10:53 am

chitwnvw wrote:Where'd you get new backing plates? That same guy on Samba? Sorry I am too lazy to browse through his 14 pages of parts... 8-[

after a few parts bus vendors said they would't sell me used backing plates for liability reasons, I sucked it up and bought them new from BusDepot.

a day later Ken Madson from 'thebusco' got back to me and sold me a complete set for $22.50 shipped to my door.
I bought them to have a spare set, because you can't beat the price and they are so hard to track down.

that said, if you need a set, I certainly don't NEED a spare set since you can re-use them, and would sell them for the same price.


I didn't rebuild the rear drums yet. they are well adjusted and I have some shoes left yet, but I will slowly get all the parts needed to finish off the rear end as well.

As for the super blue brake fluid, I did it because Ratwell said so. more specifically it made it really easy to know when your done bleeding, as once you see blue, your done!
Next time ill use regular colored fluid for the opposite effect, then back to blue. they also happened to sell the blue ATE fluid where I picked up my motive power bleeder adapter...
1979 California Transporter

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