Having problems with the brakes

[awall811]

I am just wondering what i will need to replace to fix the brakes. The problem i am having is that when i use the brakes they do not release at all so the brakes are rubbing pretty bad. My car is a 90 laser with 4 wheel discs and the problem is both in front and back but back ones are worse.

 

[DSM-Talon-John]

IS the pedal sticking are just the brakes. If its just the brakes you might just have a stinking brake line.

 

[EclipseGSX012]

did you check for any leaks?

 

[pballer]

did the car sit for a period of time? or did this just start happening? I had a caliper on my 1g and my 2g, one front and one rear. It would be odd for all 4 to sieze tho.

 

[laserspeeddemon]

Sounds like rust residue on the brakes. It sat for a while correct?

 

[awall811]

yea it sat for a bit and everything is pretty rusty as far as the brakes go

 

[Gary 420A RS]

go through and do some corrosion work on the brakes. take them off see if the rotors are good. clean everything up. bleed all the fluid out then reconnect everything and go through with the bleeding process all over. brakes are the easiest thing on the car. good luck. also check for a leak in the lines somewhere. if you think it might be of issue do some steal braided lines.

 

[laserspeeddemon]

Depending on the length the car has been sitting, you could either resurface them or you may have to replace them. Then do as said above. Replace the fluid entirely and bleed the lines of air.

 

[awall811]

i was thinking i may need new calipers because they dont like to release the brakes

 

[AWDPetmitsu]

Chances are your calipers have seized, especially if they are the original ones. I would replace all of them. It's best to replace them in pairs if you're just doing one axle, but in your case, I would replace all four.

 

[toybreaker]

Sometimes, a logical aproach is best way to find a problem like this. You could replace some very expensive parts, only to find the master cylinder was adjusted incorrectly.

One of the best ways to narrow down a problem like this is determine if it really is all four wheels that are dragging. If you drive the car a couple of miles, and then feel the wheels, you'll feel the heat put into the wheel from a dragging brake. (Don't touch the caliper itself, you may get seriously burned)

You can also put the car up on jack stands and check each wheel for drag.

If it really is all four wheels dragging, it may be a problem at the master cylinder/pedal linkage.

At any rate, it's an excellent place to start.

When you press on the brake pedal, is there any free play? (it should move at least a half an inch before it gets solid).

Does it move smoothly, and return to the same spot? There could be a problem with the pedal mechanism/master cylinder adjustment that is not allowing the master cylider pistons to fully retract. When the master cylinder pistons return fully after a brake application, they uncover a pair of thermal compensation ports in the master cylinder bore. This allows the fluid to flow to and from the reservoir as the brakes get hot, and the fluid expands. Anything that interferes with the piston uncovering that port will cause the brakes to drag proggressively worse as the car is driven, and the fluid is heated.

Debris can block these ports as well.

Another way to check for a problem at the master cylinder is to squeeze the pistons back into the calipers, and evaluate how easily fluid flows back into the reservoir.

For the fronts, just pull the slider bolts out, and remove the caliper from the carrier. The 90 model year front calipers are a single piston design. You want to squeeze the caliper piston back in to the caliper bore. In a perfect world, you can do it with your thumbs, usually, you have to use a little more persuasion. I've had pretty good luck putting the old pad against the piston, and then using jumbo channel locks, or a c-clamp. Try and make it go back into the bore squarely, and slowly. You can feel it move back in, and it should go back in pretty easy and smoothly after you get it started. If it doesn't move fairly easily, put a small hose on the bleeder screw and then open the bleeder ~2 turns and try again. If it moves easily now, suspect the master cylinder and/or it's adjustment much more strongly. If they're stiff either way, the caliper may have issues.

Be sure to clean the slider pins, and their bores in the caliper carrier, and apply fresh grease on the pins during reassembly.

The rear calipers require a tool to rotate the pistons, while you push the piston back in. (Autozone and the like have this tool as a loaner. ) Don't try and force the rear pistons back in without it!!! Buy a tube of sta-lube synthetic brake grease for the slider pins while you're there. (sometimes, they only have it in little packets, same stuff,), and a can or two of brake cleaner.

Keep an eye on the fluid level in the res., you don't want to push back too much fluid and make a mess. (brake fluid will soften/remove paint) You can remove fluid from the res. with a clean turkey baster.

I have had the rear calipers sieze on a couple of my dsm's, but you can usually tell, because one siezes before the other, and it feels funky when you brake hard. It does happen though. You can usually tell because the brake pads will be noticeably tapered/worn at an angle, or the inner or outer pad will be smoked, depending on whether it's the sliders, the piston, or the e-brake mechanism that's siezed.

Also, make sure the handbrake mechanism works correctly. Have someone apply and release the handbrake, while you watch the lever arm on the rear calipers. It should apply and release cleanly. If the booties are all torn up on the cables, they can get water and dirt inside, and get sticky, tease: as well as freeze in wet/freezing weather, ask me how I know , no wait, don't )

And, always be sure to pump the brake pedal several times before starting the car, to bring the pads back up to the rotors.

Good luck, and please, keep us posted with what you find.

 

[TheMadCheshire]

Toybreaker pretty much summed it all up. I do want to add that the special tool required to turn the rear pistons back can be had at an autozone. However, I found that a pair of needle nose pliers worked just fine. I had to keep them clamped together tightly, but it saved me a few days because the tool was rented out . Poor me. The second caliper I used a pair of vice-grip needle nose pliers and it worked even better.

Goodluck. Keep us posted.

 

[awall811]

Thanks for all the help it may be a while before i can get to work on it ### its kinda cold round here right now and i think they may have seized because even when i try to pry them apart so it doesnt rub it still does some wheels arent as bad as others though but thanks again for all the help and i will post whatever i find hopefully in the short future

 

[44pirate]

I there an adjustment to make for the rear brakes or are they self adjusting?
It seems that my front brakes are doing too much of the stopping.

 

[laserspeeddemon]

Thats the way ALL cars work. When you brake, the weight transfer to the front. THat is why your front brakes are signifigantly larger then the rear.