no brakes

Moderator: Moderators

no brakes

Postby my79monza » Mon Jul 04, 2016 2:05 pm

I have never had this happen before but it's happening now.
I can't get any brake pedal on my 79 Monza.
Everything is new, I converted it to power brakes with new parts.
I tried with me-y vacuum bleeder all around, no brakes.
Tried manual bleed, depress pedal crack bleeder repeat until no air.
Did RR then LR, no air in line no pedal either, won't even move wheel cyl at all.
With manual bleed I cant even get fluid out of either front.
Equalizer/combination valve is new also.
Never had this happen before.
Did I get a bad rebuilt M/C or am I doing something wrong.
User avatar
Posts: 813
Joined: Sat Jul 18, 2009 10:34 pm
Location: Washington, Iowa

Re: no brakes

Postby cjbiagi » Mon Jul 04, 2016 3:11 pm

Merle, did you bench bleed the MC before installing it? That is generally the first thing to do. Then bleed the RR and then LR moving on to RF and finally LF. Some proportioning valves have a button or something to push...I have never had one like that but you should get fluid out of the front calipers by simply opening the bleeder valve and allowing it to gravity bleed. Also, make sure the front calipers are mounted on the correct side of the car, the bleeder valves have to be up on top not at the bottom of the caliper. All new components mean a lot of air in the system, did you change everything at once? Also, when manually bleeding you need to open each valve and have someone push the pedal down, then before they let it up close the bleeder and then let pedal up. Keep repeating this process until you see no air in the hose from the bleeder to your catch can. As another test if this doesn't work you can get some fittings and plug the outlets of the MC. You should have a firm pedal, if not then the problem is in the MC, could be air trapped or a bad one.
Clyde.........75 Monza 2+2
User avatar
Posts: 8382
Joined: Sun Jun 25, 2006 2:37 pm
Location: Glenwood, Illinois

1975 Chevrolet Monza

Re: no brakes

Postby avewhtboy » Tue Jul 05, 2016 9:01 am

Another thing to keep in mind when changing from manual brakes to power brakes, the rod on the pedal goes in a different position for the two. If you don't have that set up correctly you may encounter problems like what you are talking about.
User avatar
Posts: 573
Joined: Thu Sep 24, 2009 11:06 am
Location: Stone Mountain Georgia

Re: no brakes

Postby 76wagon » Tue Jul 12, 2016 12:24 pm

I've been having similar problems with my brakes but not as bad, I can bleed and bleed mine but can't get a good pedal. Here's my current theory- I used an aftermarket booster with a Monza master. Everything bolts up fine but I think the booster isn't allowing the piston on the master to return all the way. I haven't started pulling things apart to check yet but all the weird problems I've been happening are making sense now. Over the weekend I added a spring to pull the pedal arm a little further ahead and it helped. If you're using an aftermarket booster you might need to adjust the plunger. Might be something to check...

User avatar
Posts: 374
Joined: Tue Mar 06, 2012 2:54 pm
Location: Kitchener, Ontario

Return to Suspension, Steering, & Brakes Tech

Who is online

Users browsing this forum: Google [Bot] and 1 guest