1992 ABS help needed

[Dave]

Truck has rear ABS only. In a nut shell....rear brake line rusted out (very small leak, never even lost any measurable amount of brake fluid in master cylinder), replaced brake line, can't get any brake fluid to rear brakes. Problem is ABS valve/module. For no apparent reason, brake fluid all of a sudden won't flow through ABS valve. The fuse is good. Before I "fix" or replace the ABS valve, is there anything electrical I should check? Is there an ABS relay anywhere? It just seems very weird that all of a sudden the ABS valve failed right after the line was replaced. The truck has been on jack stands for 3 weeks now and I really need to get it done. Thanks.

Dave

 

[ZMan]

I had the same thing happen to my truck, what i did though was just remove it, and bought a proportioning valve from summit racing. Then took the light bulb out of the dash. I know thats not really fixing it, but that might be the cheapest/easiest way to get it back on the road again, i have a feeling youll have a hard time finding a good one in the junkyard.

 

[Dave]

I seriously considered that but what keeps me from doing it is the sue happy people in the country and the scum lawyers that support them. It don't plan on having this thing much longer. If I sell it and the buyer gets in an accident, I'm liable to get my pants sue'd off, even if it's not my fault. I keep reading what a half @ss ABS system this thing has. It never did work very well. Yeah, I'd like to just get rid of it.

Dave

 

[ZMan]

Well you could sell it "as is", and make up a bill of sale stating that and have the buyer sign it. But besides that, the abs unit itself does have a bleeder on it, its rather large and on the front side if i remember correctly, try opening that, i had no luck with it, but you never know if it might work for you. I hope someone else chimes in on this, im not sure if there is a procedure where you might have to cycle the abs unit when bleeding, though i didnt have to when i first replaced a rusty line years ago. I removed my abs when i put rear discs on and couldnt get it to bleed.

 

[tx3nc]

The abs hydraulic control unit is on the inside of the frame on the driver's side at the firewall. It might be blocked with rust, dirt or other foreign material. You might try removing it and seeing if you can flush it out with brake cleaner.

The HCU has two solenoids. One to block brake pressure to the rear brakes and one to dump brake pressure to an accumulator. The two work together to keep the rear wheels from locking up. The are available refurbed for about $125.

The problem might not even be the HCU. Did you replace the entire line fromt he HCU back to the rear hose? If not, the hose or the remaining old line might be blocked with corrosion or dirt. I would first try disconnecting the brake line at the HCU have someone pump the brakes and see if you get any fluid out. Then move back along the brake line checking for fluid flow at each/any connections till you find the blockage. Good luck.

 

[Dave]

Well you could sell it "as is", and make up a bill of sale stating that and have the buyer sign it.

Unfortunately in the great state of NJ (and other states), that signed piece of paper means absolutely nothing. People still get sued and loose.

Dave

 

[Dave]

The abs hydraulic control unit is on the inside of the frame on the driver's side at the firewall. It might be blocked with rust, dirt or other foreign material. You might try removing it and seeing if you can flush it out with brake cleaner.

The HCU has two solenoids. One to block brake pressure to the rear brakes and one to dump brake pressure to an accumulator. The two work together to keep the rear wheels from locking up. The are available refurbed for about $125.

The problem might not even be the HCU. Did you replace the entire line fromt he HCU back to the rear hose? If not, the hose or the remaining old line might be blocked with corrosion or dirt. I would first try disconnecting the brake line at the HCU have someone pump the brakes and see if you get any fluid out. Then move back along the brake line checking for fluid flow at each/any connections till you find the blockage. Good luck.

I replaced the complete line from the control unit to the "T" on the rear axle housing. The complete line from the control unit to the wheel cylinder bleeders has been blown out with compressed air. With somebody pressing on the brake peddle, loosen the "IN" line on the control unit, I get plenty of brake fluid. It's definately the control unit. Next step is to remove the control unit and clean/flush/inspect it. I don't want to spend any money on this truck because I want to get rid of it. Plus all the brake parts I've had to buy (for various vehicles) over the last couple years have all been Chineese junk. The remanufactured stuff has been junk too. I'm willing to spend more money to get something good but you can't even get something good anymore.

Dave

 

[cvar]

Don't forget to take lotsa pix of your RABS rebuild. Nobody else has posted photos of the inside of this thing. You can be first. The trailblazer. I may be following in your footsteps, some day? I recently replaced all my brake lines, but left my MC and RABS alone. Mine still works, for now (knock wood), but I've read the RABS is prone to rusting on the inside.

 

[armadillon]

Unfortunately in the great state of NJ (and other states), that signed piece of paper means absolutely nothing. People still get sued and loose.

Dave

I'll be honest though, if they're of the mindset to sue you for that, they'll find a way to sue you for something else even if the ABS is working properly. I wouldn't really worry too much about it. Just get the brakes working.

If you do have them sign a copy of an As Is bill of sale, they'll have a VERY hard time convincing a judge that it is currently your fault. Especially if you tell them up front that any repairs done were by you AND the bill of sale releases you from any responsibility of mechanical failure. I'd say good f'ing luck to them trying to file a suit against you.

Although lawsuits are common in NJ and I get customer calls every day about it, people are stupid and don't take the simple precautions to protect themselves. The As Is bill of sale should serve you just fine.