Pulling to the left.

[John S.]

Had my '71 stock deluxe bus about three years, two years on the road.
Just noticed a pull to the left upon braking.
I put in new rubber brake lines and rebuilt the calipers two years ago.
Prior to me getting the bus, the master cylinder was redone and a new servo put in. Jacked it up and noticed with brakes applied the right did not grab as hard. I just spend a fair amount of time and some money and put on two new O'Reily's rebuilt calipers. My "jacked up with brakes applied" test seemed to tell me both sides were gripping well after the new calipers were put in.
While doing this, I pumped all new fluid into the system, bled and adjusted the rears.

Test drive reveals nothing has changed
The left front was noticeably warmer than the right front also.
It seems that the right front is not working as hard.
What's next, changing out the soft brake line again?

Questions:
1.) Should I change out the metal lines too?
Could they be rusted internally?
Maybe the T is clogged up?
2.) She rolls straight and my alignment checks say that's OK.
Would an alignment be of any help?

Thanks

[Abscate]

One of the pistons/calipers could be seizing up.

Look at all four faces of your brake rotors after a run - all the annuli (plural of annulus - the area of a surface bounded by two concentric circles) should all have the same mirror surface r of the rotor surface, all four should have the same inner and outer radii.

If one is different, that piston or caliper is hanging up.

Look at the left side first, then the right.
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[mikedjames]

One thing to check is the camber angle.

My stock 1973 disk + drum braked bus was unpleasant after I changed the front ball joints and in the process moved the camber nut by mistake, one side was almost vertical, while the other was at 0 deg 30 minutes.

It was pulling gently to the left all the time while driving, and braking was even worse.

I have also had issues with an aftermarket rear brake drums going oval, so that the rear brake adjustment resulted in brakes that barely worked one side, if they were adjusted to 'just binding' at two points in their rotation , 180 degrees apart.

Rear drum brakes do a fair amount of work too, hence the need for the proportioning valve to reduce pressure when braking hard.
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[John S.]

Thanks.
Yes, rebuilt calipers were just installed.
The pads are looking very even.

I assumed the one caliper was hanging up, even though I just rebuilt it
not all that long ago.

Now I have two fresh ones on there and the same issue.

I think maybe the hard lines are corroded internally, maybe.....
I see where I can get those from Bus Depot.

I have already changed out the rubber lines.
The hard lines are the only thing I have not changed out.

A professional alignment is cheap enough.
I just have done my own "string method" toe alignment, not camber.
She does track pretty straight and true, however when driving.
Just swerves left under braking.

[Danwvw]

If you don't drive them at least once a month maybe once a week the calipers plungers can get hung up. They respond well to just cleaning and greasing. Probably still in pretty good condition. If the pads get worn down that will do it too. If you have a little brake fluid leak on a rear drum that will cause it too, you may have to pull the drum's and look. They need annual maintenance if the bus is not garaged, cleaned and painted etc light oil on the backing plates and other up painted parts will help the rears. Be careful not to get oil or grease on the shoes and inside the drums.

This one was leaking at the wheel cylinder plunger and did not show outside the drum but was making my bus pull, it eventually messed up the bearings.

After repairs:

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1960 Beetle And 1679cc DP W-100 & Dual Zeniths!

[John S.]

Nearly a daily driver.
I have checked everything up front.
I see no rear leaks (new wheel cylinders two year ago) but will pull the drums.

I may try a professional alignment.
And look into the Bus Depot hard lines.
I'm wondering if, after nearly forty eight years, the metal lines
and tee (front, left to right) might be a bit corroded/clogged.

[Danwvw]

Mine ate through where two metal lines were touching each other up front. Failed during an emergency stop. It's almost always a caliper hanging though. Does it pull when you use the emergency brake to stop?
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1960 Beetle And 1679cc DP W-100 & Dual Zeniths!

[jtauxe]

I have the same problem, but in mirror image -- pulling to the right under braking. 1975 Type 2.

So, if it is a caliper misbehaving, is it repair or replace?
If replace, should both L and R be replaced together?
_________________
John
"Travelling in a fried-out Kombi, on a hippie trail, head full of zombie..." - Colin Hay and Ron Strykert
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[John S.]

Dan,

Just ran out and tested that theory.
I still pulls to the left when using the pedal.
Brakes straight as an arrow when using the handle (emergency brake).

Problem is up front.
But again, it has done the same thing with two different sets of calipers.
The fresh rebuilt ones I just put on today....

Both calipers are equally warm.
The slits in the camber nuts are both facing equally (by eye) to the rear.

[John S.]

jtauxe,

Whatever you do to one side, do likewise to the other.

As I have done here.
I put two new rebuilt calipers on.

[SGKent]

if it pulls to the left it means the caliper on the right front is not working at full capacity. The e-brake test pretty much eliminated the rears. Do make sure your tires have correct pressures in them in case one is going flat.
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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

[John S.]

Tire pressures are equal up front.
Five psi higher in the rear.

Does the alignment theory make sense?

[Mispeld]

Have you checked your suspension? Worn beams, tierods, ball joints etc will cause pulling when braking. Get it up in the air and see if you can move the wheel side to side and up and down.

I had a vehicle that pulled, and everything looked fine. I ended up putting a large pry bar in the control arm and it moved! The shop couldnt even find it. Shop told me it was a rear caliper sticking. They were full of shit.

20 years ago I had a type 3 that pulled bad. The beam was worn on one side.

Edit" previously overheated rotor or glazed rotor can also cause pulling. If you had a sticky caliper at one point, your rotor(s) may need to be turned
_________________
Tom
1977 Westy. 2.0 Fuel Injected.

[John S.]

My suspension is tight, or so it seems.
The problem is up front; proven by the straight braking using only the E brake.
I think by putting on two new rebuilt calipers I can hopefully rule out sticky calipers.
I am planning on an alignment as soon as humanly possible.
I did notice some slight wear "rounding" if you will, on the outside of the left tire when I had it off today. Not horrible but the tire didn't want to stand tall on the tread when off the bus and kept leaning toward the outside edge.
I redid a lot of things when I got the bus including a new set of Hankook RA08 tires.
So whatever wear there is has happened in less than 10,000 miles; perhaps the camber is positive on the left side. This may have caused the tire to start wearing and any positive camber effects may be exaggerated when braking.

[Danwvw]

Sometimes you can check out breaking in the dirt by a series of 10 mph stops and seeing what is sliding and what is not.
_________________
1960 Beetle And 1679cc DP W-100 & Dual Zeniths!

[SGKent]

I rebuild my own calipers to avoid getting someone else's min-wage or flat rate rebuilt junk. Sometimes it can be something like you forgot to add the shim plates and a piston is cocking in the bore.
_________________
“Most people don’t know what they’re doing, and a lot of them are really good at it.” - George Carlin

[Abscate]

[John S.]

Yes, as I had said, I originally rebuilt my own calipers.
I changed to rebuilt ones (had to turn the pistons to line up correctly with the plates) and have the same problem.

Same problem; two different sets of calipers.
I probably wasted money by replacing them but I think that proves the calipers are likely not the cause.

She's at an old school alignment shop now.

[TomWesty]

Did you measure the rotors?
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[John S.]

Rotors have about 5,000 miles on them.
New German steel; they were replaced when calipers were originally rebuilt.
No damage, they're like new.

I tried to buy new pads when I got the rebuilt OEM calipers but they gave me 14mm thick ones SO I didn't change the pads. That is one thing common to before and after the new calipers.
I'm ordering the proper 10mm thick ones but will try a pad switch, left/right in the meantime to see if the pull follows the pad set. Might be a glazed pad set on one side.