ethan169

ok so the car is an 87 formula, 305 M5 if that matters.

The original problem was that when using the brakes the car pulls pretty hard the the left. and when coming to a stop light and then letting off the brakes when stopped you can feel the left caliper still sort of clamping down on the rotor for a few seconds.
so about 5 days ago i put brand new well remanufactured calipers and a new set of brake pads on the front, i was able to bleed the right one but i could not get the bleeder valve open for the left caliper. so i put the wheels back on and took it for a little spin. seems to do the same thing and the pedal is now a little spongy, most likley from the lack of bleeding on the left side. either way i have to get back to school so i drive down to school seems to be ok.
today i am driving and the car is pulling pretty hard to the right when not braking then hard to the left when braking. it seems that the right caliper is now sitcking. and eventually it starts to smoke here and there and REAKS like brakes.
so any seggestions as to what i should look at first. or what could cause this problem?
any advise is greatly appreciated and if u need more information about the problem just ask. i am trying not to make this post too long but also not wanting to be to vague.
thanks a bunch
Ethan

strokermotor91

First of all Welcome to TGO. First thing you would need to do is get that left brake bleeder screw loosened up. When you you bleed you brakes, start at the furthest brake from the resevoir, which would be rear right, then rear left, front right and front left. Make sure you don't run out of brake fluid when doing this. After you finish the brakes shouldnt be spongy anymore. This is the first thing you should try!

bilms01

I would replace the hoses. The spongy pedal is the air you couldn't bleed.
The pull is probably collapsed hoses assuming the caliper slides are free

408irocz

I would say bad brake hoses try jacking up safely using jack stands if availiable loosen bleeder port while turning tire to see if wheel frees up if it does your hoses or a bad valve is present if no change occurs it has to be a bad caliper

ethan169

ok i will try a couple of things, i am at school and quite limited to what tools i have with me. but any one know off the top of their head what size wrench i should be useing for bleeder valve? or what to do with a slightly rounded bleeder valve? also do i have to bleed the rears if i havent touched them. i dont want to risk breaking the bleeders, they are pretty old.
Thanks for all the help guys
~Ethan

dennisbernal91z

iTrader: (2)

I had the same grabbing issue. Except I have all new SS lines and all braided hose with new C5 Z06 brakes. I also have a new MC. The only thing not new is the booster. and I am replacing that in the next few days. If thats not it, I guess I will go back and change my braided lines again. I got them 5 years ago.

What about the lines being bad would make them keep holding on? I don't see that as being the root of the problem. I kinda think a funky working booster might be the problem. But I dunno. Oh and I know its not my propotioning valve. I have a new adj. one in there. All new lines..... Ugh I hate this.

Seems to happen less when the motor is under a lot of vacum. Again leads me to think that the booster is at fault.

bilms01

Make sure the caliper slides/pads slide freely and the caliper isn't in a bind.

If the hoses collapse internally the pressure cannot release properly keeping pressure on the caliper. Unless the hoses are completely shot after a period of time pressure will bleed off.

Make sure the proper brake fluid is used. IIRC the silicone/synthetic and any petroleum based liquid get is the brake system it will play h*** with anything rubber in the system and cause similar problems.

SpitotRs305

how doesn a brake hose or tube...collapse? exactly the shear nature of the system would seem to PREVENT that IE forcing high pressure fluid into the line... notice how small the reservior is... we arent talking about pumping 10 gallons through these lines... maybe a couple of ounces... but yes only DOT 3 brake fluid not DOT 5...

when you took off the old pads... was one of them cracked? why didnt you replace the rotors and bearings at the same time?

AND dont forget that this car has more than front brakes... it also has rear brakes... you will find those much more fun... i recommend those be done ASAP as unless you have seen them done to the car i doubt anyone else has bothered... oh yeah wear some type of gloves OR buy the specialty tools... after you get fishhooked one or two times by those great springs you will wish you had the right tools

bilms01

Rubber and rubber compounds do deteriorate, and when they do they leave little pieces floating in the fluid. You ever noticed how you brake fluid looks dirty or wonder why people talk about flushing the system. Time, moisture and sometimes fluid contamination accelerate the process. After a while of deteriorating the inner lining becomes soft and may develope small holes in the lining and making to porous. Now the little brake fluid molecule guys like to hide in these hole so the don't have to work as hard as all the other molecule guys. Pretty soon the the rubber molecules who have left their safe home in the lining and are homeless decide to stand at the door of these holes to ask for handouts. Sort of the ugly people trying to get into a night club. Eventually the sidewalk (center of the hose) gets filled. When you step on the brake pedal you force the hard working fluid molecules to run past the rubber guys real fast making them move. When you release the pedal the workers only walk home from work (tired I guess) and the rubber guys are still in the way, because the worker guys have used the energy you gave them by pushing the pedal got them past in the first place there is not as much pressure pushing them to return to the wife of 20 years and screaming kids, so they don't push as hard trying to get back by the rubber guys. By the way the rubbers guys are pretty pi**ed that the were knocked out of the way in the first place. (it wasn't pretty, mass carnage, kind of like 5 really really drunk guys and only one fat ugly chick in a bar at closing time) Anyway the worker fluid guys are too tired to fight just to hear the wife and kids complain so they just hang out at the all night bar next door, which keeps the brake on that corner at least partially applied, till the rubber guys either fall asleep or get too tired to keep the workers from stumbling home. When to workers finally do get home the brake is magically released completely.

dennisbernal91z

iTrader: (2)

I am using Dot 3 and have always used it only. And the pins are Very lubed and slippery. I can shake the caliper on them with my hand. The problem can't be by the brakes themselves cuz I went from stock to C5 and the problem continues. It must be a line, booster or MC.

Just not sure witch one.

ethan169

ok i am using some standard DOT3 for fluid. i have a feeling that the pins are not free. i didnt lube them with anything and that side has the old pins, the side that is not sticking has brand new pins. what should i lube them with caliper grease? or brake fluid?

dennisbernal91z

iTrader: (2)

any kind of grease should be fine. All purpose stuff. Something thick so it will stay put.

SpitotRs305

so let me get this straight... you are saying floating rubber particals... are stopping the fluid movement in the line... rubber must have got much stronger than i remember... but for the sake of argument say that was possible... now that sort of thing would only be a temporary blockage IE you would experience the dragging only for short periods of time after braking...

maybe you could better explain how that actually works without trying to go along with some retarded story...

antman89iroc

I had the exact same problem and after replacing everything else in the brake system the problem still existed. I pulled the front brake hoses and I couldn't even blow through them. Wierd too because I was able to bleed them before. Anyway after I replaced the hoses the problem went away. $20 and an hour of time fixed it. I had spent hundreds of dollars and countless hours trying to run the problem down just because I couldn't accept that the problem was that simple. Lesson learned. BTW Thanks third geners.

bilms01

I am not sure if it will help but it only takes a couple minutes, pull up on the brake pedal and see if the brake light switch adjust any. A click or two could be enough to make it hang a little. Gm had problems with the Monte Carlo and Malibu platform with front rotors heating and warping. They said the problem was the brake light switch was misadjusted holding the pedal depressed a little causing too much residual pressure in the ft calipers. It may help just a guess easier than replacing the booster. Just throwing out a thought check to see if the pedal pivot is free letting it return to fully up/released position.

I would apologize for the retarded story but I won't. I have been an ASE certified technician working at dealerships and aftermarket shops longer than you have been alive. If you search for the same problem you will find more often than not hoses have either fixed the issue or at least helped. Read Antmans response.

I am NOT saying the rubber STOPS the fluid movement it just RESTRICTS the volume of the fluid flow. It is not the size of the reservior that determines how much fluid flows, it is the amount of travel the caliper and /or wheel cylinder piston has to move. You are correct it is not a huge volume that is why any restriction in a hose has the capability of a large effect.

Try something: get a paper straw, get it wet then blow through it. It will collapse. Put 1200 -2000psi fluid pressure through a weak deteriorated rubber hose and the same thing will happen. After is collapses ther will be a peroid of time before the pressure you put downstream of the restriction to bleed back through it.

Read the last line of what I posted again. that's why I wrote it the way I did. It is only a retarded story if you don't create a mental image and picture what happens in milli-seconds. Sometimes there is residual pressure on one caliper when you hit the brakes on is already partially applied, when the other one applies you feel it. If the car pulls left when you hit the brakes the right side has a problem. Assuming suspension is not the cause.

dennisbernal91z

iTrader: (2)

bilms01: It is def def not the brake switch. i am not using stock...anything. My brakes turn on due to a pressure change that is seen in my line lock. With that said, thanks for the advice. From what you are describing I am kinda thinking my brake hoses might be the problem. They act just like what you are describing. I am a mechanical engineer and after you mentioned the pressure and the line collapsing, i felt all my fluid dynamics classes rushing back into my head.

Even though my lines are braided, I was a fool in high school and would let the calipers hang from them a little from time to time. This might have caused a premature failure of the line even though they are SS braided. I will hold off on the booster replace and do the lines first. I am off to overnight some to my house from summit right now. Thanks!

SpitotRs305

okay so we will follow your logic blowing through the straw... yes i could see that colapse when wet... if you were trying to force large volumes of air through the straw... the point here is your arent moving a large VOLUME of fluid only a small amount as you said so how would that fluid build enough velocity to actually colapse the line after overcoming the all of the pressure built in the line... we arent talking like 10 PSI here this is more hundreds of psi...

but again your whole theory relys on the fact that the master cylinder is actually sucking the fluid back... it wont... but if you read the first post entirely you would have noticed the fact that he put a set of reman calipers on... and only bleed the RIGHT side NOT THE LEFT which is the side that was "GRABBING" THERE FOR YOUR THEORY doesnt apply as there isnt any fuild in the brake line any more and the unbled caliper would not be able to exert enough force to do any braking

by the way you might have been ASE certified before i was born but that would only make me 14... that would be news to my mum.

ethan169

ok, so im thinking its the brake hose, well ill look into it today, i appreciate everyones input by the way, my daily driver is an evo vIII and the only forum i have used for a while was evolutionm.net which is great. i remember trying to use 3rdgen.org before and i didnt get any response plus it didnt seem like that many threads were active. glad to see that i stand corrected.

Thanks a lot guys, ill let you know how it turns out
Ethan

joe350

Awesome job describing the problem there bilms01, I would have just used physics terms but it wouldn't have held anyone's attention the same way. I had the same problem and it was indeed the rubber hose. Happened on both sides. Don't let it go on for too long or you will burn your caliper and warp your rotor (yeah, I did it.) Its a very easy job, but you definately need to bleed the line after you reattach the caliper. If you break the bleeder valve, don't worry. A new caliper with trade in of the old one is only like $12.