97 Chevy Blazer Brake Bleed

[allyn849]

I had a leaking brake line on the driver side rear. I changed the line and now cant bleed the brakes in the rear because ther is no fluid going to the back. Does the ABS have anything to do with this and ifso how can I remedy.

[b1lk1]

I'm not positive, but I believe you need a Tech II scanner (or equivalent) high end scanner to get the ABS module to cooperate for the bleeding process if you got air in it.

[4x4 blazerguy]

You are going to have to balance your proportioning valve. It is a safety valve that allows you to still have brakes in an occurrence like you had. You'll have to locate the valve not sure where it is on the Blazer. It as a rule is on the drivers side under master cylinder on the frame. You'll have to crack the lines on the valve going to both front & rear brakes. Sometimes it will center itself other times you may need someone to push the brake pedal gently a little & hold it & tighten lines & try to bleed the rear.
The ABS has nothing to do with your problem all the ABS is a set of sensors on the calibers that read brake pressure.

[manicmechanix]

I think you probably have air in the abs unit. If you have ABS that should take the place of the porportioning valve. I think there's a procedure to bleed the ABS that doesn't require a bi-directional scanner. I think you cycle the key on and off a few times or something similar. I don't remember. I know that's not much help but I think a chilton repair book for your model would have it.

[MT-2500]

Originally Posted by allyn849

I had a leaking brake line on the driver side rear. I changed the line and now cant bleed the brakes in the rear because ther is no fluid going to the back. Does the ABS have anything to do with this and ifso how can I remedy.

4W or rear wheel ABS?
As said the centering valve will shut off one end.
Some times craking a bleeder on other end will help trip the centering valve back in place.

With 4W ABS brakes sometimes turning the key on wil help bleed the ABS unit.

[4x4 blazerguy]

Originally Posted by MT-2500

4W or rear wheel ABS?
As said the centering valve will shut off one end.
Some times craking a bleeder on other end will help trip the centering valve back in place.

With 4W ABS brakes sometimes turning the key on wil help bleed the ABS unit.

Thanks for the info on the ABS. On my 97 I have disc fronts & drum rears I didn't think the drums had ABS. I didn't think 4 wheel discs were available in 97. Is this correct? I know my fronts have ABS I have tested that many times off-road. Traveling at 60+ MPH on dirt roads when out of nowhere comes a wash out & I hit the brakes the fronts keep trying to not lock up. Then when I'm about to hit the wash out I let off the brakes & hit the gas. I guess too much dirt bike time.
Thanks

[allyn849]

Thanks to all for help. I found no metering valve on my blazer. It is straight from ABS to the front brakes and rear. I also was told to dis connect the battery and the ABS will reset itself and this worked. I now have plenty of fluid to the rear and good brakes. Thanks again

[b1lk1]

Originally Posted by 4x4 blazerguy

The ABS has nothing to do with your problem all the ABS is a set of sensors on the calibers that read brake pressure.

This is completely wrong. ABS uses wheel speed sensors to read the speed of each wheel and in turn will reduce brake pressure to the wheel that is locking up.

Glad you fixed it. I meant to chime in earlier that there is no external proportioning valve on these trucks.