alright, my car has NO brakes whatsoever, new pads, shoes, rotors, and drums, wheel cylinders are still good. AND i just swapped out my master cyl. still no luck, my master isn't taking any fluid outta my resivoir. BUT i bench bled it so i KNOW the master cyl i put on is good... so my only assumption is tyhat there is something wrong between my pedel... and my master cyl. if so what could it be? and how can i fix it?
please i need this car back on the road ASAP
thanks in advanced
98 Sunfire GT LD9
KYB, RTX, AEM, MAGNAFLOW, MORE TO COME.
Delphi ABS ownd?
Your car is the one that has the black abs box attached to the master cylinder correct?
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yes it is
98 Sunfire GT LD9
KYB, RTX, AEM, MAGNAFLOW, MORE TO COME.
ABS module should not hinder braking though. It would only control the pulsation of the brakes under lock up situations. Personally, I would re-check the bleed. If you have an air bubble in the system somewhere it could potentially take up the fluid displacement from the pedal. Did you bleed the ENTIRE system or just the calipers / rotors that were changed?
If that is not the case, the only other option is the "plunger" (for lack of a better word) that pressureizes the master cylinder. If that is not moving then that could cause no braking, because nothing is moving. Go under your dash and press the brake pedal and make sure that push rod is moving freely...
Smile! All things fade with time...
Reject wrote:ABS module should not hinder braking though. It would only control the pulsation of the brakes under lock up situations. Personally, I would re-check the bleed. If you have an air bubble in the system somewhere it could potentially take up the fluid displacement from the pedal..
Actually you're quite wrong, when the ABS module is pulled off the master cylinder you hear a Zing sort of noise, almost like something is unspooling,
That is the sound of a motor gear unwinding under tension, this motor is what provides the pulsation to an offending wheel.
So when you pull the ABS pack off the motor basically closes off the rest of the brake system off and you get no brakes, hence why nothing is leaving the resivouir
One has to "re-home" the motors in order to bleed and get fluid into the system.
You can add power to the motors on top of the black box or you can raise the rear and spin a tire above 10mph and that should re home everything.
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cavmania wrote:Reject wrote:ABS module should not hinder braking though. It would only control the pulsation of the brakes under lock up situations. Personally, I would re-check the bleed. If you have an air bubble in the system somewhere it could potentially take up the fluid displacement from the pedal..
Actually you're quite wrong, when the ABS module is pulled off the master cylinder you hear a Zing sort of noise, almost like something is unspooling,
That is the sound of a motor gear unwinding under tension, this motor is what provides the pulsation to an offending wheel.
So when you pull the ABS pack off the motor basically closes off the rest of the brake system off and you get no brakes, hence why nothing is leaving the resivouir
One has to "re-home" the motors in order to bleed and get fluid into the system.
You can add power to the motors on top of the black box or you can raise the rear and spin a tire above 10mph and that should re home everything.
Clarification;
If the ABS module (Meaning controller - electrical component) went out, how would that effect hydraulic efficiency? All of the braking systems that I have ever encountered fail (Again the electrical aspect) to an open position. You can still brake just fine, it's the pulsation that doesn't happen. I could see what your saying being the case if the actual pump / valve system locked up or unspooled.
Smile! All things fade with time...
thanks guys, i havent actually had a chance to go check it out yet, but i am thinking it is the plunger as well. thanks for the help and ill keep ya posted on wether or not thats the problem.
98 Sunfire GT LD9
KYB, RTX, AEM, MAGNAFLOW, MORE TO COME.
alright... turns out that the rod is moving freely from my pedal on... so im at a total loss here, i have no idea what else to try.
98 Sunfire GT LD9
KYB, RTX, AEM, MAGNAFLOW, MORE TO COME.
Colton MacLean wrote:alright... turns out that the rod is moving freely from my pedal on... so im at a total loss here, i have no idea what else to try.
Hi,
The piston in the Master Cylinder is spring loaded to return to rest position. In that position it goes back far enough so that the fluid intake port allows fluid into the cylinder.
IF the pedal rod (for whatever reason) is preventing the full return of the piston and never allowing the fluid port to put fluid in you will never have brake action.
You've bled it? Got fluid out?
Started with the Right Rear wheel then Left Rear and then Right Front and finally Left Front?
You bled it till the fluid ran new and clear?
If you pump the pedal rapidly three or four times does it become hard? This tests for air pockets.
If you get a hard pedal and just push on it does it slowly sink to the floor?
Dave
Hi again, not sure how or IF I can edit a post
If no fluid is entering the cylinder, I'd loosen the nut on the booster to add length to the rod (I don't think they are adjustable on this car), this is just to diagnosis, maybe wedge a shim in to keep it level if you need to. Step on the pedal, if you now have fluid moving this is your problem
If it works, why is it a problem? Did your parts house give you the wrong cylinder? Did you put something back together wrong?
Pull out the new cylinder and compare it very closely with the old. Measure the depth of the brake pedal rod hole between the two, are they different?
Maybe you've got a piece of debris in the hole which in essence lengthened the rod?
If you loosen the brake lines at the cylinder and step on the pedal, does brake fluid come out? (don't get any on your paint!!!!)
If so, you problem in down line from the cylinder and not the cylinder at all.
Dave
