87 abs pump
Instructor
Joined: Nov 2011
Posts: 147
Likes: 0
From: Florida
Check Brakes hoses c4
Exact same symptoms mine had two weeks ago.
Replace rear brake hoses works great now.
Both hoses were plugged. The abs has only one line for both back brakes, at least on the 86, I thought what are the chances both hoses were plugged but they were no fluid passage at all.
Replaced them everythin is great stops on a dime.
good luck
g
Replace rear brake hoses works great now.
Both hoses were plugged. The abs has only one line for both back brakes, at least on the 86, I thought what are the chances both hoses were plugged but they were no fluid passage at all.
Replaced them everythin is great stops on a dime.
good luck
g
Safety Car
Joined: Apr 2011
Posts: 3,660
Likes: 22
did you d/c the rear line at the ABS module to see if fluid makes it that far?
if it does run out of the ABS module, then search the steel lines for a pinch point. Its been done before by floor jacks and even debris flopping up hitting the lines.
IF the fluid does NOT come pouring out of the ABS module/pump body..then you will need the FSM and some help rebuilding the thing. Most just replace. Salvage units are on FleaBay, ABS computers still for sale at catalog stores and online.
Inside that ABS module...may as well be witchcraft. I've never seen anyone repair or rebuild...only replace. A pump replacement, sure, not tear into the whole thing.
And you;re positive the master cyl is supplying fluid from BOTH lines that exit the master?
The line for the rear may be damaged....between master cyl and ABS or even caliper.
The work of splitting front & rear is done at the master...the ABS has a route for each wheel..but there is no junction for any 2 or 4 to be linked together again.
if it does run out of the ABS module, then search the steel lines for a pinch point. Its been done before by floor jacks and even debris flopping up hitting the lines.
IF the fluid does NOT come pouring out of the ABS module/pump body..then you will need the FSM and some help rebuilding the thing. Most just replace. Salvage units are on FleaBay, ABS computers still for sale at catalog stores and online.
Inside that ABS module...may as well be witchcraft. I've never seen anyone repair or rebuild...only replace. A pump replacement, sure, not tear into the whole thing.
And you;re positive the master cyl is supplying fluid from BOTH lines that exit the master?
The line for the rear may be damaged....between master cyl and ABS or even caliper.
The work of splitting front & rear is done at the master...the ABS has a route for each wheel..but there is no junction for any 2 or 4 to be linked together again.
Racer
Joined: May 2004
Posts: 295
Likes: 3
From: Newton NJ
I had the same problem except mine was the right front caliper. I changed the hoses with the same result. I purchased a used ABS unit off of *bay and that fixed the problem.
I did found the old unit had a lot of debris near the check valves. Very important to flush the brake fluid regularly.
Hope this helps
I did found the old unit had a lot of debris near the check valves. Very important to flush the brake fluid regularly.
Hope this helps
Safety Car
Joined: Apr 2011
Posts: 3,660
Likes: 22
I agree withcmontel 100% on the flushing fluids...
the ABS controller is a complicated little machine and it has many delicate parts that MUST operate freely and correctly...after all, its YOUR life in its hands...
Brake systems wear internally and that wear material stays in the fluid. There is no filter in a brake hydraulic system. I know I've seen my cups turn black and have solids laying in the bottom of the cups...
I highly advise getting self bleeder screws so you can crack one open with a hose on the nipple, get in and pump away and flush the fluid thru each line until clear. These self bleeders allow one person to do the job because they have a check valve that lets fluid OUT but not air IN. I also support the use of hi-temp fluids and/or synthetics.
the ABS controller is a complicated little machine and it has many delicate parts that MUST operate freely and correctly...after all, its YOUR life in its hands...
Brake systems wear internally and that wear material stays in the fluid. There is no filter in a brake hydraulic system. I know I've seen my cups turn black and have solids laying in the bottom of the cups...
I highly advise getting self bleeder screws so you can crack one open with a hose on the nipple, get in and pump away and flush the fluid thru each line until clear. These self bleeders allow one person to do the job because they have a check valve that lets fluid OUT but not air IN. I also support the use of hi-temp fluids and/or synthetics.
Race Director
Joined: Apr 2002
Posts: 10,036
Likes: 346
From: Anaheim CA
Maybe this article would be helpful:
http://www.corvetteactioncenter.com/...abs/index.html
It's quite common to fix an ABS problem by replacing the relay(s).
http://www.corvetteactioncenter.com/...abs/index.html
It's quite common to fix an ABS problem by replacing the relay(s).
