Drum Front Brakes - Car pulls left when stopping. Thoughts

definitely a master problem, the piston in the master has a large spring that should assist in returning the pedal plus the pressure when created when you push down should return the piston.
 
Ah sh#% !!!! Installed New disc brake system on front (did have drums.) New Booster and New Master Cylinder (set up for disc/drum.) I know the MC is good after testing it with just the back brakes. I plugged the MC front brake line hole and tested the back brakes - all good - good pedal pressure and good stopping. After hooking the front brake line (disc) back up to the MC the car does stop but I am still having the same issues. 1: car pulls to the left when brakes applied and 2: pedal does not come all the way back up and brakes drag. The only things I have not done are replace the lines themselves and replace the distribution box. Could the issues I am having occur from a faulty distribution box? Thanks . . . JIMB
 
Do you have the original rubber lines on the front, they can collapse internally and cause your problem
 
Brand new caliper lines for the new disc system.
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the catalog does show a specific proportioning valve for 70 with discs but that would be front rear balance not left right. The master is definitely for disc/drum? Do you have a way of hooking up a low pressure air line to the front port of the master and see if you can blow air into the reservoir? There should not be a check valve in the front.
 
the new MC I bought has a proportioning valve with it. So right now I have two lines coming out of the proportion valve down to the distribution box (on the frame) then out to the wheels. The MC i bought was for a disc/drum set up. How do I tell if there is a check valve in the front ?
 
The check valve test was the low pressure air blowing back into the reservoir. If you can think of another way to confirm no restriction on the port on the master that would work. You may be able to see a difference by looking at front versus back port, the back would have a check valve.
 
Here are the results from the latest test. I plugged up, at the proportioning valve, the front brake line. So the only brakes I had were the back brakes. Hard pedal and car does not pull left or right. I just wanted to confirm the issue I am having is in the front. But, the pedal is still not coming all the way back up to the top. The brakes are not dragging but I have to pull the pedal (not much but a little) all the way to the top. Why would this be happening? I am about ready to ditch the original distribution box - don't really need it anymore.
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Another question. There are two holes on my brake pedal arm. I have the brake rod going to the second hole? Is that right? I am guessing one hole is for manual brakes and the other whole for boosted brakes. Which hole is for which application?
 
Just to make sure. I WD40 the brake pedal to make sure it was good and loose. And after further review on the brake pedal coming up . . its not. I have a good hard brake pedal (remember only for the back) and it stops about half way to the floor. So thats good - pedal not going to floor. But it will not return . . not even a little bit. So is this a test I can perform with just the back brakes and the front plugged up?
 
ok. next question. If I plug the front and back brakes at the proportioning valve should the pedal return to its normal operating position?
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Brake return problem fixed. While pulling the brake pedal back up with your foot seems easy . . not so easy with the hand. I loosened the bushing where the brake pedal swings on and made sure the brake pedal swings freely. Now the brake pedal returns all the way back up to the top with no problem. No onto why the car pulls to the left when the front brakes are hooked up. :)
 
OK, thats strange did you overtighten the bushing or that was the way it was when you got the car? Since the master is no longer an issue, there are other reasons for pulling. Do you have any worn suspension components, tie rods, center link, idler arm, etc? Are the wheel bearings properly adjusted? Tire pressure the same left and right? has the car been aligned? No missing shims from the upper control arms where they attach to the frame?
 
The car came that way to me. I just assumed it was the MC. Oh well. I bled both front calipers and all the good. There was a lot of air in them because I had the front line off while I was testing the back brakes. Just tested out and the car still pulls to the left. I am thinking this is NOT a brake issue. Both brakes bled fine. There are no leaks. Pedal returns back to its normal operating position. I am with melsg5 on this one . . I am also thinking now its a suspension issue. There is a pop that is coming from the LEFT front when I brake really hard. Not sure what this is. And to boot, I am not a suspension guy. it would be hard for me to tell if something were amiss with the suspension by pushing or pulling on arms or parts. I hate to say this . . I might have to take it a local mechanic who has a lift and such. The pain this causes me.
 
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Issue area found. I happened to take the car over to a friends to see if he could feel the pull and maybe give me his thoughts. We had a nice drive around and he could not figure out why the car pulls to the left. He also tested the brakes going backward and the brakes worked great - no pull or anything. While, after a nice drive we dropped him back at his house with no real thoughts on the issue. As I pulled away he asked me a question, I could not hear him so I stopped and he noticed the front left wheel move back - like its not suppose to. I think the brakes work fine. Instead I have an issue with the front left suspension. I am thinking one of the a-frame bushings is bad or something like that. Would like to hear some ideas on what would make the wheel pull back 1-2 inches when stopping. Cracked A-frame . . bad A-frame bushing, etc.
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one of the common items on my list above are the alignment shims, if they fall out you will have that A-arm rocking back and forth. They are on the upper A-Arm where the two bolts attach it to the frame, not the bushing bolts.
 
Never done or seen that before. Any helpful links or pics?
 
Looked this morning. Shims are still there. I guess I will need to dismantle everything to find out where the issue is coming from. Any words of wisdom before I start ???
 
Took out the driver side upper and lower control arms yesterday. And I think I found the issue. One of the bushings on the upper control arm was shot. See picture. This bushing (or whats left of it) fell, yes fell, out of the control arm when I took it off the frame. Would like to hear some thoughts on if this is a big issue and could have a negative effect on car suspension and stopping.

While I have everything off I went ahead and bought new tubular upper and lower control arms, new front springs and new shocks (yes, for both sides.) Everything should be here next week. After I get the driver side back together I will take the passenger side apart and rebuild with the new parts. Should have a much better ride and handling.

Thanks . . . JIMB
 
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