Bypassing the ABS system

[Alfonso Gomez]

ad I've had it with my 87 Coupe's ABS system. After 4 different mechanics, the right front caliper still locks up. The last mechanic told me the modulator valve is probably to blame. In Puerto Rico it costs $1913.00 and I will definitely not pay that price. I was told that the ABS system can be bypassed either by connecting the lines where the ABS unit is or by installing 1985 Corvette brake lines (85 Corvettes don't have ABS). Anybody has done it? My car has new pads, rotors, master cylinder, new calipers, new brake hoses. The problem: lift the front of the car, start the engine, press the brakes, shut the engine, and manually try turning the right front wheel. It will not turn. After a while, if you force it, it will turn but the pads "drag". HELP..........

 

[Radar]

Have you had the wheel disk brake rotor runout checked on all of the wheels? I read somewhere that a rotor with runout constantly works the pads back and forth and causes hydraulic pumping/binding to occur.

When the pads are dragging, if you open the bleed screw on that wheel cylinder, does the pad/piston release? If not, you may have a sluggish or corroded caliper bore/piston. If it doesrelease, then the fluid pressure is up and that may be the master cylinder or that runout pump-up problem I read about.

Can't help much more. Good luck on solving that problem. I personally would not try to diable the ABS.

Radar

 

[SPANISHVETTS]

This sounds more like a caliper – rotor problem. Tell your mechanic to keep an open mind and not blame the most expensive or misunderstood parts before a through diagnosis of the entire system has been preformed.

When the calipers are bleed on an ABS system the hoses need to be clamped to keep trash from being forced back into the modulator. There is a thread somewhere on this forum on the subject.

Try this:
Rebuild or replace the caliper
Have the rotors turned or replace them
PURGE the entire system, run several cans of brake fluid through the system and dispose of the remains.
Refill the system with new fluid and bleed the system following the manual.

ASK C4C5specialist for more ;help,
His info is always spot on :BOW