Brake Pull

[BlackMetal]

Got my car up and running and haven't enjoyed it so far.

Brake pedal is spongy even after a few sessions of bleeding, and worse than that, I get a nasty brake pull to the right.

Old school "pump and hold" bled the brakes in the driveway, used a Mityvac at work, and after the Mityvac I let them gravity drip for a while too. Still getting like 2" of sponge in the pedal. Have also pumped down the accumulator two or three times to get the bubbles out of it.

Car stops straight with light brake application but if I make any attempt at a hard stop the car wants to go half a lane to the right. Have to correct with the steering wheel. Car drives straight the rest of the time so I don't think the alignment is in question.

Stock brakes were weak but never had these problems. Now I've upgraded to the LS1 front brakes, other than that it's still the stock powermaster and stock rear drum. These problems have appeared after installing the new front brakes.

I need to make sure the rear drums are adjusted to see if that will help the pedal travel, but the brake pull has me stumped.

Didn't get any grease or fluid on the pads that would cause a "grab".

This isn't fun. Installed a bunch of stuff the past few weeks to make the car faster, yet I've taken 5 steps backwards in terms of feeling safe on the road.

Where should I start?

 

[raymon823]

make sure you have anti sieze on you caliper pins. sounds like your left caliper is not working properly check to make sure the piston in that caliper moves free. I would anti sieze that also just a little though. Are the caliper you have used?

 

[PaCemkr86]

sounds like a problem in the brake hose..

 

[TURBOTWIN2]

Just a thought, make sure you've got the calipers on the correct side. The bleeder screw should high up top. If both bleeders are below the middle of the piston area more towards the bottom than top, then they are switched. You won't get a good bleed, air will be trapped in the caliper, resulting in a spongy pedal and erratic braking. Also check the amount of fluid coming out of each caliper when bleeding, should be similar side to side.
Pace & Raymon are on target about the hoses & anti-sieze. There is usually a white line along the length of the rubber hose and it shouldn't be twisted after installation. Also, a brake hose can collapse inside and not show externally, gives you nothing but grief.
Good luck. Not to worry, you WILL eventually fix it.

 

[kraus]

check pins like they said and also calipers right side if all that is right needs a hose.

 

[TKGN1]

You have got some pretty good advice. I have always lubed the slider bolts up with anti seize as well when doing the LS swap. Also I put braided lines on when installing, takes the hose issue out of the equation.
You'll get it fixed, when you do you'll crap yourself first time you nail the brakes real good, those LS brakes rock.

 

[zeus87gn]

Agreed, already some good advice given here.

I would like to add that if the steering wheel wants to pull away when it pull to the right, the problem is in the front brakes. If the whole car pulls (you really don't fell it in the steering) it's in the rear adjustment.

HTH,
Z

 

[KILL4PEACEUSMC]

I had a car the other day at work that had been "shot gunned" with all new calipers, hoses, prop valve, you name it. I checked line pressure and found both sides even, dug a little deeper.......bad lower control arm bushings! Bingo. Make sure the front end is tight, I know you stated that it all happened after replacing you brake stuff, but we have all seen stranger things!

 

[BlackMetal]

Thanks for the tips so far.

>> Yes the calipers are used but supposedly "inspected and verified" with this kit I bought from a fellow board member. Other people have used his kit and been happy so I trust that the calipers are good.

>> When you do the LS1 swap, you don't change the brake hoses, and as I mentioned this didn't happen with the stock brakes, so the hoses haven't changed. I will check that the hoses aren't twisted, but other than that, internal collapse of the hose is unlikely, it was fine before. The hoses are routed a little differently than stock because the connection point at the caliper is in a different location, but of course I would not have routed them in any way that seemed twisted or restrictive.

>> Calipers are on the correct side, bleeders up at the top.

>> I will go back and grease everything up just to be sure.

>> It is a definite instant response in the steering wheel when braking, leaves no doubt in my mind that the front brakes are not working equally.

Could air in the system cause a pull? I.E. more air in the driver's side hose causes that caliper to grip less than the right side?

 

[JDSfastGN]

Thanks for the tips so far.

>> Yes the calipers are used but supposedly "inspected and verified" with this kit I bought from a fellow board member. Other people have used his kit and been happy so I trust that the calipers are good.

>> When you do the LS1 swap, you don't change the brake hoses, and as I mentioned this didn't happen with the stock brakes, so the hoses haven't changed. I will check that the hoses aren't twisted, but other than that, internal collapse of the hose is unlikely, it was fine before. The hoses are routed a little differently than stock because the connection point at the caliper is in a different location, but of course I would not have routed them in any way that seemed twisted or restrictive.

>> Calipers are on the correct side, bleeders up at the top.

>> I will go back and grease everything up just to be sure.

>> It is a definite instant response in the steering wheel when braking, leaves no doubt in my mind that the front brakes are not working equally.

Could air in the system cause a pull? I.E. more air in the driver's side hose causes that caliper to grip less than the right side?

yes air in the line can cause this as well. Don't rule out the hose either, they are probably old and you may want to consider replacing them anyways for a firmer brake pedal feel. (even new rubber will be better than old stuff)