Date: Sun, 16 Sep 2007 00:22:41 -0700
Reply-To: Scott Daniel - Shazam <scottdaniel@TURBOVANS.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Scott Daniel - Shazam <scottdaniel@TURBOVANS.COM>
Subject: Re: B-r-r-r-a-a-a-k-e-s
In-Reply-To: <EFD6FBE4-EFD6-48A9-9B60-84D5CEDC0DC2@NEWCLEAR.US>
Content-Type: text/plain; charset="US-ASCII"
You welcome. Did you try pumping the brakes when it happened ?
One thing I've noticed on vanagons is the red warning light, way over on the
left, for parking brake or low brake fluid ( if there's a switch on your
master cylinder res - starts in about 1985 I think ) is rather small, kinda
dim, hidden behind the steering wheel and easy to not notice.
But there should have been some brake left.
How old is the master cyl ? It's quite possible to have internal leaking on
a master cylinder....
The two 'systems' in tandem ....there's a leak from one section to the
other. On a master cylinder with this condition- if one half failed, like
a badly leaking rear wheel cylinder, I would expect the brake pedal to go to
the floor.
I had this brakes issue experience recently - 85 Vanagon poptop weekender.
Brakes just never felt that good. Pedal wasn't firm, nose didn't dive under
hard braking etc. I 'knew' something was up, and I had gone through the 4
brakes at the wheels, and changed all the brake fluid.
I happen to have a brake MC around that I've been saving ...it came out of a
vanagon who's entire interior burnt up too - but other than being slightly
blacked on the outside , it seemed like it might work. It sure does.
Braking is what you'd expect now.
And..........'some people' wouldn't have noticed anything was wrong. The
pedal was high, it was firm too, but I could tell that the brakes just were
not working correctly.
One check you can do is use the brakes pretty hard, like going downhill, and
get them pretty hot ( not fading, just pretty warm ) and then check the temp
of each brake. Best is with an infra red temp gun. You'd like to see
roughly equal front temps, side to side, and same at the rear, and both ends
pretty warmed up. I think I've seen 250 degrees F pretty easily on front
disc brakes. I would expect rear to be not quite as hot as the fronts.
There's a pressure limiting valve to reduce pressure to the rear brakes.
Brake boosters - I rarely, rarely ever find a bad one of those. If we were
speaking of Dealership ripofffs I'd mention a case of a Honda dealer that
replaced the booster and master cylinder on a civic with only about 50K on
it. I knew the booster wasn't likely shot. I called them up, they said if
the MC fails and gets brake fluid in the booster, you have to replace it.
That was probably a 700 dollar master cylinder, on a Honda only a few years
old, and I doubt it really needed a booster. Vacuum brake boosters seem to
last really well, like indefinitely 'almost.'
Scott
-----Original Message-----
From: Kai Mei [mailto:kai@NEWCLEAR.US]
Sent: Saturday, September 15, 2007 11:43 PM
To: Scott Daniel - Shazam
Subject: Re: B-r-r-r-a-a-a-k-e-s
Thank you scott... I have felt the brakes go to the halfway point on
my saab and that scared the piss out of me... That was a 20 yo car
and I would expect it to work the same way in a vanagon. To the floor
is unacceptable.
On Sep 16, 2007, at 12:57 AM, Scott Daniel - Shazam wrote:
> Vanagons have their brakes split front-rear.
> Those older volvo's had two brake lines to each front caliper, so
> that one
> 'half system' was half of each front caliper, and one rear disc.
> One of the
> few cars with this system. My 88 turbo 740 sedan has normal a front-
> rear
> divided brake system I'm pretty sure.
>
> Theoretically, if a rear wheel cylinder goes out completely, you'll
> have a
> low brake pedal and some front brakes only.
> You take a master cylinder that's 15 + years old, a neglected brake
> system
> in general.....the pedal could easily go to the floor.
> I find it impossible to believe there weren't warning signs and
> symptoms for
> quite a while, like for a couple years even.
> Systems change very slowly - say shift linkage, or brakes , or
> shocks -
> people don't notice that things change because the change is so
> slow. But
> if you hopped in an identical van with everything tight and proper,
> you'd
> immediately know yours wasn't right.
> Same if an experienced tech drives your nearly warn out brakes -
> they know
> immediately if they're any good, that something isn't right.
> Scott
> -----Original Message-----
> From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On
> Behalf Of
> Kai Mei
> Sent: Saturday, September 15, 2007 6:55 PM
> To: vanagon@GERRY.VANAGON.COM
> Subject: Re: B-r-r-r-a-a-a-k-e-s
>
> I had no idea that a leak in any part of the brakes would result in a
> total failure. My 1972 Volvo would leave 3 braking wheels if any one
> cylinder or line failed.
>
> Do many other cars/vans eschew redundant or at least dual (diagonal)
> brake line systems?
>
>
> On Sep 15, 2007, at 6:40 PM, Joseph Fortino wrote:
>
>> I blew a pass wheel cyl this past week. i was going to do the work,
>> but not in
>> my own place at this time.. time to get blasted with a BILL ahh,,
>> new rear breaks
>> now,, but what a mess the wheel cyl left me.. puppy went to the
>> floor also.. e-break time
>>
>> Joe
>> 85gl piggy bank?
>>
>> -----Original Message-----
>>> From: Kim Brennan <kimbrennan@MAC.COM>
>>> Sent: Sep 15, 2007 2:55 PM
>>> To: vanagon@GERRY.VANAGON.COM
>>> Subject: B-r-r-r-a-a-a-k-e-s
>>>
>>> I'm thinking there are not many better places for this to occur.
>>>
>>> I was in my back yard with my Syncro Westfalia. I had finished
>>> unloading and storing my canoe, and was in the process of turning
>>> around to drive around to the front yard. I have a bit of a
>>> slope, so
>>> after pulling forward a bit, I pushed in the clutch and started to
>>> roll backward to get around the corner. I pushed my foot onto the
>>> brake pedal and....it's that sickening feeling of right to the
>>> floor.
>>> As I'm accelerating downhill (going backwards) I'm fiercely pumping
>>> the brake pedal (not thinking, just reacting.) Nothing. Just a
>>> bit of
>>> resistance as the brakes aren't engaging.
>>>
>>> I stop on the level then drive around part of the way to the front
>>> yard (in granny gear). Then stop with the emergency brake. I pull
>>> off
>>> the top of the console so I can see the brake reservoir. Fluid is in
>>> there. So I pump the brakes and watch as fluid is leaving
>>> there...never to return. Blast.
>>>
>>> So I get out and start looking for drips. Nothing in the rear
>>> (SmallCar rear disc brakes). Nothing on the front left. Ah. Drips
>>> from the front right. Swing around for a better view.
>>>
>>> Hmm. Not good. Rear half of wheel well is soaked with brake fluid.
>>> But WHERE is it coming from?
>>>
>>> Looks like right at the junction of the metal brake line with the
>>> caliper (SA big brakes). A curious failure point.
>>>
>>> Time to get the brake cleaner out and use it on ....shockingly
>>> enough, the brakes. I use the stuff for so much else it is going to
>>> feel weird using on the brake system.
>>>
>>> Oh, well. I needed to flush the brake fluid anyway....yah, keep
>>> telling yourself this is good.
>
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