Car pulls to right on braking

[MtnBiker]

Flatout and I spent the afternoon installing stainless brake lines and new pads all around on my Gen IV today. On the drive home the car was pulling to the right on braking? It never did this before and has me quite worried since I am going to track at CoTA this weekend. We installed Brakeman 3s on front and OEM pads on back.

Any ideas why it's pulling right?

[FLATOUT]

Did it do that when we were bedding them in? I didn't think it did, maybe it's still just wearing in? Not sure as those are the first set I've done, I'm sure someone here can help.

[MtnBiker]

It did not do that until I got down the road. I think you may be right just needs to wear in?

[VRYALT3R3D]

low tire pressure
bent wheel
warped rotor
allignment

[FLATOUT]

low tire pressure
bent wheel
warped rotor
allignment

Only one on there that it could be would low tire pressure. John check that :D

[slitherv10]

Sometimes the caliper hardware is loose. This can cause the affected brake to apply unevenly resulting in a pull condition. Loose bolts or worn hardware can cause the caliper to cock when it applies.
•
Another possible cause of brake pull is mismatched friction material. There is a big difference in the coefficient of friction between organic lining and semi-metallic lining.
•
Brake linings can also be the source of a pull if they become contaminated with grease, oil, brake fluid, etc. Simply cleaning the pads will not rid the lining of contaminant, as the contaminant will tend to absorb into the lining like a sponge. Contaminated lining should always be replaced after the source of the contamination is determined and
repaired.

The Hose Effect, check the braided lines you guys installed
An often-misdiagnosed cause of pull is a collapsed brake hose. The hose will look OK on the outside, but the inner liner will cause a restriction on the inside. A brake hose problem like this can take two forms. First, it can act like a restrictor in the line. Second, it can act like a check valve.
In the first case, with a restriction the car will pull to the side with the good brake hose upon initial application of the brakes, but after a second or two, the pull goes away. Because the caliper needs a relatively large volume of fluid to move the piston, the side with the collapsed hose will apply later than the one with the good hose. This is because it takes longer to get enough fluid volume into the caliper to move the brake pad against the rotor. This is why the pull can be extreme on the initial pedal application, but the pull goes away as the fluid slowly moves the piston.
In the "check valve" situation, fluid will freely flow into the caliper, but will not return to the master cylinder. This can mimic a stuck piston, as the caliper will fail to fully release.

a hot brake. The heat indicates friction. Remember that the hot brake is not necessarily the problem side. For example, if the right front caliper is stuck and not applying, it will be cool and the left front hot. The vehicle will also pull to the left.
Compare how easily the dragging wheel spins compared to the opposite side by turning it by hand. If it's difficult to turn, loosen the bleeder screw. If the wheel turns freely after relieving the pressure in the caliper, the caliper is OK. If only one wheel is affected, it's probably the brake hose. To be sure it's not something upstream, reapply the brakes and release, then loosen the hose at the fitting on the body (not at the caliper). If the problem goes away now, the hose is in good condition

1. remove calipers open bleeder valves
2. re-open calipers to max position
3. grease posts
4. brake dust cleaner on rotors and outer parts of caliper assembly
5. re-install calipers
6. re-bleed the calipers
7. test it out to see it if helps

[MtnBiker]

Holy crap slither. Thank you for the detailed response!!! I will say that I wasn't overly careful about not possibly getting brake fluid on the pads. Now I know there would not have been much fluid if any got on them, but it was on my hands from time to time and possibly I transferred it to the pad during installation (but it would only have been a very small amount, thumb print ?) I did clean the rotors with brake cleaner spray. Could this be the problem, and how do I fix it? I thought that using the brakes would burn it off.

I am fairly certain we didn't crimp the lines. But I can check that visually. I cannot definitively say that the pull lessened/was worse at initial application. I need to go drive it again to verify.

[FLATOUT]

John, relax and put a few more miles on the car and see if it persists.

[Nine Ball]

I'd go with the simple and obvious, you likely have air trapped in the lines on the left side(s) calipers. Causing the right side to brake sooner, pulling you right.

[MtnBiker]

Tony, thanks. I think that's the problem.

[St.Char]

I'd go with the simple and obvious, you likely have air trapped in the lines on the left side(s) calipers. Causing the right side to brake sooner, pulling you right.

Yeah, have too agree. What method did you use to bleed the lines?

[ViperGTS]

I'd go with the simple and obvious, you likely have air trapped in the lines on the left side(s) calipers. Causing the right side to brake sooner, pulling you right.

:t1236:

[FLATOUT]

Yeah, have too agree. What method did you use to bleed the lines?

Motive power bleeder, starting at passenger rear and working our way forward. Doing the SS lines obviously disrupts multiple points in the system. We had it all bled well and took it out to bed the new pads in and everything was great. Possible there could be a bubble or two in the drivers front caliper. I am surprised it didn't show itself on the test drive but no problem we'll get it taken care of.

[St.Char]

Motive power bleeder, starting at passenger rear and working our way forward. Doing the SS lines obviously disrupts multiple points in the system. We had it all bled well and took it out to bed the new pads in and everything was great. Possible there could be a bubble or two in the drivers front caliper. I am surprised it didn't show itself on the test drive but no problem we'll get it taken care of.

That's a great line bleeder, so I'm sure you did this but I'm going to ask anyway, did you start with the inboard valve, then outboard, then inboard again...this procedure should have gotten all the air out. If it continues to pull, you might bleed the front brakes again, just as a process of elimination, however sometimes certain brake pads will have a beveled end and the other end is blunt, if I'm using pads like this, I'll take my dremel and soften up the blunt end edge of the pad, this creates a smoother contact surface. Just a thought...

[FLATOUT]

That's a great line bleeder, so I'm sure you did this but I'm going to ask anyway, did you start with the inboard valve, then outboard, then inboard again...this procedure should have gotten all the air out. If it continues to pull, you might bleed the front brakes again, just as a process of elimination, however sometimes certain brake pads will have a beveled end and the other end is blunt, if I'm using pads like this, I'll take my dremel and soften up the blunt end edge of the pad, this creates a smoother contact surface. Just a thought...

Yes that's the method I used. I re bled his driver caliper today just for good measure and all seemed fine. Hopefully he'll get the chance to bed them in again tomorrow and it will work itself out because the systems seems bled and ready to go.

[MtnBiker]

The brake pedal feels completely normal, engages up top and stays very firm. I would say there is no air in the system. On the way home last night I must have gone from 60mph down to almost stopped (anti-lock engaged) about a dozen times. The left front just doesn't seem to want to bed properly. The rotor has black streaks, and makes a grinding sound.

From Brakeman web page: With any compound, if you observe black streaking on the rotors or poor performance, the pads were not properly bedded and need higher temperatures.

I should generate enough heat coming into turn 12 at CoTA this weekend!

[FrgMstr]

The brake pedal feels completely normal, engages up top and stays very firm. I would say there is no air in the system. On the way home last night I must have gone from 60mph down to almost stopped (anti-lock engaged) about a dozen times. The left front just doesn't seem to want to bed properly. The rotor has black streaks, and makes a grinding sound.

From Brakeman web page: With any compound, if you observe black streaking on the rotors or poor performance, the pads were not properly bedded and need higher temperatures.

I should generate enough heat coming into turn 12 at CoTA this weekend!

You probably want to do that before you get there! :D

[FLATOUT]

Beat the shit out of that thing! Run it up to 100 and hammer it.

[Bill Pemberton]

..........and it could be something as simple as mismatched pads. Never been a fan of using different brands of pads or two with different designed uses. The Brakeman's are a track pad , whereas the
OEMs are more multi-purpose and though many think the backs just go along for the ride , good chance the system is fighting completely different rates of heat buildup and grip? Just a thought as seen issues over
the years that come down to the simplest thing.

Also , did not notice anything about how you cleaned off the rotors prior to installed new pads , or if you even did? Different pads leave layers on the surface and can keep a new set from bedding properly.

[MtnBiker]

I didn't clean the rotors.

Well, yes Andy is correct I wiped them clean.

[FLATOUT]

Bill I think he wiped the rotors clean with break parts cleaner, no scuffing or anything extra.

[MtnBiker]

Lol. I'm heading to Mexico tonight.

[Bill Pemberton]

Have done the Brakeclean route often, but have also had to scuff them also when changing to a different compound/pad ----- had to do on various cars not just Vipers and saw it more often
in older cars with no ABS. Just another thought, as lots of good ideas here in this thread.

[FLATOUT]

Thanks for your help Bill.

[Bill Pemberton]

No problem, lots of good ideas and thoughts on this thread -- very positive and concerned help all around!

[mjorgensen]

The brake pedal feels completely normal, engages up top and stays very firm. I would say there is no air in the system. On the way home last night I must have gone from 60mph down to almost stopped (anti-lock engaged) about a dozen times. The left front just doesn't seem to want to bed properly. The rotor has black streaks, and makes a grinding sound.

From Brakeman web page: With any compound, if you observe black streaking on the rotors or poor performance, the pads were not properly bedded and need higher temperatures.

I should generate enough heat coming into turn 12 at CoTA this weekend!

You should NEVER let the ABS engage when bedding pads, they need to smoothly transfer pad compound to the rotor and rapidly locking and unlocking pads on the hot rotor will cause all kinds of problems.

[MtnBiker]

Oh, now you tell me :). Makes sense I guess. So, please tell me what the proper procedure is. Do I go 100 to zero but no ABS? JonB suggests there has to be air in the system and that's why the left front isn't applying enough force to properly bed.

[FLATOUT]

I have no idea how there could possibly be any air in the system. It has been bled 3 times at this point, and the last two times showed zero air in the system when bleeding and nothing but clean fresh fluid. Did you go out and try to re bed them? I really think that front drivers pad isn't properly bedded yet .

[MtnBiker]

Agree on all counts bro. Didn't get a chance today.

[Steve M]

Maybe try something like this if you can't seem to get them to bed properly?

http://www.brushresearch.com/brushes.php?c1=6

[mjorgensen]

Oh, now you tell me :). Makes sense I guess. So, please tell me what the proper procedure is. Do I go 100 to zero but no ABS? JonB suggests there has to be air in the system and that's why the left front isn't applying enough force to properly bed.

If there is uneven pad transfer on the rotors now it could be best to use a 3M sanding disc to clean off the surface of the rotors first or you can try the re-bedding again by doing;

"If rotors were previously bedded using a different manufacturer’s brake pads; then it is strongly recommended that the used discs (rotors) be reconditioned/turned and meet minimum specification requirements."

Here is some great advice to follow and Q&A;
http://www.ctbrakes.com/faqs.asp#bedding2

[Steve M]

This is a good read too:

http://www.stoptech.com/technical-support/technical-white-papers/-warped-brake-disc-and-other-myths