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Hammy
Ok, I know absolutely nothing about brakes so excuse the stupid explanation..

Is it possible for the brake pads to be squeezing too tight when they're not supposed to be ?
I have the rear of my car up on jack stands, and (with the e brake off of course), the left rear wheel is somewhat difficult to spin. How easy should it be to spin? The right rear also sounds like its rubbing slightly on the pads, though I'm not sure if this is normally how it's supposed to be? But the left rear definitely has some resistance.

If it isn't supposed to be this way, is it just a simple adjustment or am I going down another deep and dark path... ph34r.gif

This is a shot of the left rear pad...
bondo
You started down the deep dark path when you got a 914.. lol2.gif

Search for "venting clearance".. it will answer all your questions.. and generate that many plus two new ones. smile.gif

Short answer: No, that's not normal, there should be a measurable gap.
Hammy
Thanks smile.gif

after searching, if I'm not mistaken, the allen socket on the outside of the caliper is for adjusting venting clearance?
if so, they both appear to be stripped on both sides. wacko.gif
What now...
Ctrout
QUOTE(bondo @ May 19 2006, 05:53 PM) *

You started down the deep dark path when you got a 914.. lol2.gif

Search for "venting clearance".. it will answer all your questions.. and generate that many plus two new ones. smile.gif

Short answer: No, that's not normal, there should be a measurable gap.

I think the gap is either .006" or .008". I set mine just slightly tighter that the recommended specs to get a better "pedal feel" and I get a rather annoying chirp at very low speeds so I'm thinking of just going with what the books say.
klink
There is actually an inboard and outboard adjustment. I believe it takes a 4mm allen wrench. The inside one goes through a hole in the trailing arm. I think I followed a Tech article on Pelican when I did mine. Easy to do if you go step by step. I would suspect a possibly stuck caliper binding the rotor. There is a member here who rebuilds calipers, I believe his name is Sean. Probably a good idea to contact someone who knows specifically about these brakes. If the venting adjustments are not making a difference it may be time to address the calipers. One of the mechanics at my work told me once "make sure it steers and the brakes work, that's all that really matters". I put that on top of my priority list. Good Luck!
Qarl
Eric Shea rebuilds the calipers to better than new.

Check venting clearance on inside and outside with good set of feeler gauges.

If you are bleeding your system... pump and bleed... and recheck and readjust your venting clearances (they will settle in and change the settings once bleed).

Eric_Shea
Thanks Karl,

Venting clearance is the issue. You do not want to drive this way. It can be detrimental to your caliper and rotor. It may seem fine now but as it heats up and expands there can be problems.

Regarding the adjusters. Yes, there are two. One for the outer pad and one for the inner pad. The inner adjuster is not so easily accessed through the hole in the trailing arm. The inner adjuster cover is probably stripped as well meaning, it may be a good time to pull the caliper. Couple of things that may help in the interum:

1. Make sure you loosen the 13mm lock nut on the outer adjuster before you attempt to move it. It sounds like the DAPO didn't do that and stripped them for you.

2. Try the 4mm. There are even some 4.5mm wrenches out there but the adjuster should be a 4mm. If it's too far gone you may have luck with the SAE equivalent. It's a 9/64 and slightly larger. We stock new adjusters and they're $25.00 each if you decide a rebuild is in order and you want to do it yourself.

3. If you meet with any resistance on the inner adjuster cover (it's a threaded plug with another 4mm hex slot in it), use heat directly on the cover and try again. If it's stripped then the caliper will have to come off. There is not enough surface area in the 4mm hex slot to overcome the threaded area of the plug when it's stuck or rusted... they simply strip.

Good luck and call if you have any questions.
Andyrew
You on the ground and drivable now?

4mm wrench.. Mine were 4.5mm(PITA to find and adjuster for.. I made one.)

If its just ever so slight, then drive it sunday.. I'd like to see it.
Meaning, if you can spin it by hand without using alot of effort. Its only a couple miles, it will be fine. (and if it screws up.. I have spare pads and rotors for 4 lug... lol)


Eric, side note. do you have the rear rebuild kits? Most places dont, I need to order some, I decided to just "freshen" up the rear brakes, (bad idea...) and a couple things went wrong.. I could not for the life of me get the inside piston back in, so I used a vice while spinning the adjuster, well... problems struck and so i got frustrated, and put the piston in the vice, and forced it down..... LOL

Needless to say, it didnt like me.


Eric_Shea
It's a 4mm. It was probably worn out.

Kits... yes I have them but I can't see how they would even be rebuildable at this point. You probably destroyed the threaded adjustment mechanism.
Andyrew
Oh I know.. I have other calipers though..

Actually, the spring in the piston flew off.. as did the retaining thing. (which bent btw)

Threads were intact.. The piston would not go in in the first place.. so.. I guess I figured, wth might as well give it a try before I give up and go with another caliper..
I've rebuilt 3 rear calipers and 6 front calipers... but its been a while...

Andrew
klink
Eric, my apologies for not rembering your name. I will need to keep that somewhere close because I will be needing some calipers for this restoration.
Hammy
Eric, if I find I need the rears rebuilt I definitely won't be doing them myself wink.gif
If I were to send my calipers to you to be rebuilt, would I have to wait for my actual cores to be rebuilt or do you have some already finished and waiting? I don't care about getting my originals back smile.gif


Andrew, nope not on the ground yet. Engine and tranny are in, axles are still unhooked but I've started it up a few times.

I'm having a lot of trouble adjusting my clutch and throttle cables and carb linkage. Plus I don't know if everything is adjusted right (timing and carbs) so I wouldn't want to drive it around and have something go wrong... I'm being cautious. I also am having trouble getting the muffler back on AND now I'm worried about my rear brakes. I haven't even looked at the front brakes but they were serviced (rebuilt I think) last year so I'm assuming they're good to go. But I'll definitely head down on Sunday and say hi.
Hammy
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