1998 blazer brake bleed problem
dbrasco
03-12-2010, 10:09 AM
i have a 1998 chevy blazer 2wd i replaced the drv.side rear caliper now when i try to bleed the brakes the pedal doesnt seem to get hard when i open the valve up fluid comes out but pedal doesnt go down any help greatly appreciated
spree
03-12-2010, 10:26 AM
i have a 1998 chevy blazer 2wd i replaced the drv.side rear caliper now when i try to bleed the brakes the pedal doesnt seem to get hard when i open the valve up fluid comes out but pedal doesnt go down any help greatly appreciated
I also have a 98, I had the same problem with the back drivers side. It took me awhile almost two hours of bleeding and stepping on ped., don't get frustrated, keep bleeding, working ped and caliper and soon it will work good as new.
I also have a 98, I had the same problem with the back drivers side. It took me awhile almost two hours of bleeding and stepping on ped., don't get frustrated, keep bleeding, working ped and caliper and soon it will work good as new.
Schrade
03-12-2010, 03:19 PM
If you have antilock brakes, you will have a problem bleeding if air is in the line ABOVE the proportioning valve in the brake line.
Supposedly, you have to bleed ABS with a scan tool, so you can DE-activate the ABS pressure valve. This I think is what's stopping the pedal from actually dropping when pressure is released at the bleeding wheel. The proportioning valve will not let pressure drop in one line while the other stays tight, as you bleed that line - it allows pressure to equalize between the 2 wheels, defeating the purpose of the bleed.
Possibly, you can pull the fuse that powers ABS, and do the proper bleed. I don't know for sure that this works this way...
You might have to also do each wheel, starting at the furthest wheel, and bleed til you get air. Then go to the next furthest, and do likewise, til you're at the closest wheel..
I do THIS also, which might or might not make a difference: pump the pedal several times, block it the last time with a 2x4. Go to the bleed wheel, release the bleed screw, JUST A LITTLE, and QUICKLY re-tighten. You don't want any air getting back in of course.
NEXT, remove the master cylinder cap, and then let the brake pedal return. I think this allows the fluid more easier to flow down the line from the MC. If the cap is on, then it's gonna' make a vacuum, depending on how much fluid flows down the line.
Re-cap the MC. Repeat at the same wheel 3 or 4 times, then go to the next wheel.
Do you have a helper?
Supposedly, you have to bleed ABS with a scan tool, so you can DE-activate the ABS pressure valve. This I think is what's stopping the pedal from actually dropping when pressure is released at the bleeding wheel. The proportioning valve will not let pressure drop in one line while the other stays tight, as you bleed that line - it allows pressure to equalize between the 2 wheels, defeating the purpose of the bleed.
Possibly, you can pull the fuse that powers ABS, and do the proper bleed. I don't know for sure that this works this way...
You might have to also do each wheel, starting at the furthest wheel, and bleed til you get air. Then go to the next furthest, and do likewise, til you're at the closest wheel..
I do THIS also, which might or might not make a difference: pump the pedal several times, block it the last time with a 2x4. Go to the bleed wheel, release the bleed screw, JUST A LITTLE, and QUICKLY re-tighten. You don't want any air getting back in of course.
NEXT, remove the master cylinder cap, and then let the brake pedal return. I think this allows the fluid more easier to flow down the line from the MC. If the cap is on, then it's gonna' make a vacuum, depending on how much fluid flows down the line.
Re-cap the MC. Repeat at the same wheel 3 or 4 times, then go to the next wheel.
Do you have a helper?
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