Date: Sun, 26 May 2013 16:24:29 -0500
Reply-To: raceingcajun <raceingcajun@COMMUNICOMM.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: raceingcajun <raceingcajun@COMMUNICOMM.COM>
Subject: Re: Causes of Brake Pull at Highway Speeds? UPDATE
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Neil,
Have you jacked the van up? When this thread first came out I advised
you to jack the van up, getting all four wheels off the ground. (please use
safety stands)! When you get it in the air, have a helper very slowly apply
the brakes while you try to roll both front or rear wheels at the same time.
This will tell you which wheel is causing the problem. If one wheel drags
before the other say the right drags first, check the left caliper or flex
hose, and vise-a-versa. You said the flex hoses where less that a year old,
at that time, I think I had suggested you might have some Brand X Chinese
hoses. We can do this in steps, do this step "1" and let me know what you
find.
Do you know what a "Tasmanian Devil" is, or a "Whirly-gig"? Those are
things the spin out of control, going from one thing to another with no
purpose, kind of like a dog chasing its tail. I hope your not paying each
time you go to these different shops!
You may have a bad caliper, but normally they will stick and not apply
at the same time as the other side or drag, not releasing when you take your
foot off the brake.This is not usually the O-ring but rust, or corrosion.
The O-ring is the seal keeping the fluid from leaking. After you do the drag
test, another question will be, is the boot on the caliper broken, split, or
either side leaking? One step at a time, I'm getting ahead of us!
Again, I'm willing to walk you through this as would several others on
this forum. You may contact me anytime off list, just use the E-mail address
above.
Howard
Subject: Causes of Brake Pull at Highway Speeds? UPDATE
> So another shop checked out my '81. The owner took a pry bar to the
> front end, did a visual inspection and found no issues (excessive play
> etc.). We don't think my radius arm hole repair is the issue. He
> thinks a faulty rebuilt caliper may be causing the pull. He has found
> that with some rebuilt calipers, the piston O ring (seal) may cause
> the piston not to move properly. I have far less experience than him
> so don't see how this would cause a pull while braking HARD at ~ 50
> MPH + but......
>
> How would a caliper piston O ring cause this? Like even if braking
> hard, can the O ring hold the piston firmly enough that (in my case)
> it won't allow the driver side pads to move as well (push as hard on
> the rotor) as the pass. side pads?
>
> A side note. He adjusted the brake shoes and noted that the e-brake
> was adjusted as far as it can go. I may have worded my question to him
> poorly, but I asked if backing off the e-brake adjustment would allow
> more adjustment at the shoes and allow the e-brake to be adjusted
> properly. He said "no".
>
> AFAIK, all the rear brake parts are still serviceable. If I slack off
> the e-brake adjuster, will this allow the shoes to re-position
> slightly further in (away) from the drums which in turn would allow me
> to adjust the shoes then properly adjust the e-brake?
>
> As have others, I've seen first hand how caliper rebuild quality can be
> poor.
>
> Image of a rebuilt "new" pass. side caliper on my '81. A leak sprung
> at the halves: http://tinyurl.com/pdbv7zn
>
> As such, I can see that a big brake kit might be a good investment.
> OTOH, for my '81, this means new uprights (knuckles) and possibly ball
> joints etc.
>
> Neil.
>
> On Fri, May 10, 2013 at 10:39 AM, neil n <musomuso@gmail.com> wrote:
>
>
>> At ~ 50-60 MPH, if I brake hard hands "off" the wheel, the van pulls
>> to the right. Not severely but quite noticeably. Doesn't happen
>> braking hard from ~ 30 MPH. Like I almost have to make the nose dive
>> for the pull to happen.
>
>> A shop checked the brakes, steering-front end components before this
>> trip. Brakes checked out ok but they noted "upper ball joints have
>> very very minimal play. Not a concern at this time." and that the sway
>> bar bushings are cracked but "no safety concerns noted at this time".
>> In spite of that, they said the front end was tight and ok.
>
>
>> Almost all front end and brake parts have been replaced in recent
>> years and don't have a lot of miles on them.
>
>
>> I repaired the passenger side radius arm hole at the frame.
>
>
>
> --
> Neil n
>
> Blog: tubaneil.blogspot.ca
>
> '88 Westy http://tinyurl.com/c8rlw6p
>
> '81 VanaJetta 2.0 "Jaco" http://tubaneil.googlepages.com/
>
> Vanagon VAG Gas inline-VR Engine Swap Group:
>
> http://tinyurl.com/d7gd5ej
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