Chevy & GMC Vans

Ive replaced the breaklines on TW. I bled them out but after sitting overnite they get spongy pump them 3 or 4 times they are good to go any ideas what it could be other than air in the lines. how can I get rid of this problem?

Do you have ABS? If so, I have read in various posts that an ABS brake system is very difficult to bleed properly. I am not sure how to bleed them, but I'm sure someone will be able to say or you might find it by searching old posts.

I didn't see what year your van is and there is a difference. Air won't compress thus the spongy peddle. Try starting the engine every bleed, that cycles the ABS pump. Then again an 85 won't have ABS so my reply would be to start at the Master and open every fitting and bleed like normal. Some times the rear hose is clogged and the fluid is slow to the rears. If it's an old van with high miles I'd replace all hoses.

I had a problem with air in the lines. Couldn't get it out no matter what I tried. I built a pressure bleeder out of a garden sprayer and that thing blew the air out right now.

its an 87 with no ABS. hoses are newer....

It sounds like you may have to check for a tiny leak somewhere. Check over the flares for sure. Had this happen last time I did the hard lines... One of the flairs was leaking a tiny tiny bit creating that spongy feeling.


Also sometimes I've found that a tad bit of air gets stuck mid line and you have to put a butt load of fluid through the right rear bleed screw via pumping and opening to get it out.

I always use a pressure bleeder at my work, because we flush out old brake fluid and replace it with new it makes the brake pedal firmer. As Smiley said build yourself a pressure brake bleeder from an insecticide pressure sprayer.

Do a search here or at AstroSafari archives for my indepth write up.

Once you use the pressure bleeder you wont go back to the old pump, pump, pump, way of bleeding the system. Total investment in my garden sprayer pressure bleeder is about $20.00.

I agree there is either air in the lines or a tiny leak at a fitting.

We NEED a write-up on the pressure bleeder! I know I have seen Darren's build before but a write-up for the tech articles would be AWESOME!!!!