1971 Type 2 - all brakes sticking - HELP?

[dpetrzelka]

Hoping you all may have some suggestions for solving my '71 Type 2 brake problems.

The old calipers/cylinders were failing so I just replaced all of the following:

Master Cylinder
Front Calipers / pads
Front Wheel bearings (set to correct tolerance)
Rear Calipers / Shoes
Emergency Brake Cables

I've gone thought the rear brake adjustment procedure for the shoes and then for the e-brakes.

I'm having drag/excessive heat on front brakes and rear passenger brake. To the point that driving only a few hundred yards heats them up to near seizing.

Any ideas on what could be causing the brake pressure to fail to release?
Would a vacuum assist servo cause these symptoms?

Any thoughts greatly appreciated
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1971 Type 2

[rusty busty]

Rubber brake hoses collapsed inside so the fluid won't release from the calipers?

Brake push rod not adjusted correctly?
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1978 CEII Get-away hightop

[SGKent]

make sure the booster to master link is properly adjusted. If the master doesn't fully return it will cause this. Also the rubber hoses can be at fault.
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“Most people don’t know what they’re doing, and a lot of them are really good at it.” - George Carlin

[dpetrzelka]

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1971 Type 2

[dpetrzelka]

I just took the tip off of the vacuum servo shaft (to shorten it as I read in another thread) - reassembled and symtops still the same.

I’ll try replacing the flexible sections of the brake lines, as you suggest, and see if it is those that have collapsed.

Thanks guys
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1971 Type 2

[Tcash]

Did your new master cylinder have Residual pressure valves? Yellow arrrow.

If it did they gave you the wrong master cylinder.

There should be a date on the rubber hoses. If they are more than 10 yrs old replace them.

Happy Friday
Tcash

[dpetrzelka]

No residual pressure valves—so I should be good there.

But I’ve owned this bus for 22 years and never changed the brake hoses, so it’s long over due. Is that something I can find at Oreilly/NAPA or is that an online VW specialty purchase?
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1971 Type 2

[Tcash]

They should carry them.
Start spraying the connections with rust penetranting oil and use an 11mm flare nut (line) wrench, so undone round off the metal faring nuts. IIRC the rubber hose fitting is 17mm.

Good luck
Tcash


Brake Booster

[Mispeld]

Pick a wheel and open the bleeder. If pressure is released (fluid squirts out) and you're able to move the wheel then that usually points to an internally collapsed rubber line. If nothing comes out and the wheel is still locked up then I'd check sticking wheel cylinders or calipers.

It would be rare though, for all 4 rubber lines to collapse or all 4 wheel cylinders/calipers to stick all at once. So if the above doesn't help, then I'd take a closer look at the master cylinder.

I've never seen a bad master cylinder in a hydraulic system lock everything up, but I suppose anything is possible. It's the opposite in fact... spongy or no brakes if the MC was bad.
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Tom
1977 Westy. 2.0 Fuel Injected.

[Tcash]

Usually pushrod clearance occurs when a new servo is installed. Removing the end of the servo pushrod tip may not have been enough. Just to rule out the pushrod clearance.
Jack up the left front wheel, rest the weight of the vehicle on a jack stand.
Apply the brake hard and check for drag. Note how long it takes for the drag to go away.
Apply the brake again then loosen the master cylinder mounting and see if the drag goes away.

It may be possible that the new brake fluid caused the brake hoses to swell?

[SGKent]

I'll go one better. Pick a wheel and open the bleeder. If that wheel spins then it is the rubber hose. If BOTH wheels on the same axle spin easier it is the master relief port being blocked.
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“Most people don’t know what they’re doing, and a lot of them are really good at it.” - George Carlin

[Tcash]

[dpetrzelka]

Sure enough, it was three collapsed brake lines. Two front, and the rear passenger all collapsed. I tried blowing air through them after replacing, and nothing would go through. I've owned the bus for more than 22 years, and had never replaced those lines, clearly its something that needs to be done once in a while.

After replacing all four line (as well as all of the above) its stopping better than ever.

Thank you all.
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1971 Type 2

[TomWesty]

thanks for reporting back.
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If you haven't bled on them, you haven't worked on them.
Visit: www.tomcoryell.com and check out my music!

[Wildthings]

[dpetrzelka]

They weren't too expensive at all - especially given the results.


O'reilly had three of them, but I still need to track down the hose for the rear driver's side. It is unique in that it is a male to female hose, that goes from a T fitting down to the hard line to the the rear cylinder. The other three hoses are all female/female for connecting two hard lines.
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1971 Type 2

[Tcash]

211611775C
https://www.google.com/search?q=211611775C&ie=UTF-8&oe=UTF-8&hl=en-us&client=safari