brake issues

[narfire]

Brakes were not quite right. Pushed pedal and no or very little brake untill I was right on the fire wall and then hard application to get the car to slow down.
Bled the brakes. no difference. Pumped the pedal engine off and on and no pressure build up on the pedal.
Changed out the master cylinder. Bench bled the new MC before installing. Acorn was about 1+ mm out past the face of the booster.
Bled the brakes agian ..... Took the car out and similar thing. hard brake application untill the floor. Repeated this a number of times after pulling the plunger in the booster and turning the acorn out 1/2 turn each time. Got a bit better but then had a grab and a hard pull to the left.
jacked the car up , pulled the wheel(FL) and the caliper. Pushed the pedal and could watch the piston come out. "F" clamp the piston back in easily. Cracked the bleeder valve and pumped the pedal...fluid came out. Bled the circut again and then button it up.
Started the car and pumped the brake pedal and again NO pressure build up on the pedal, car running or not..
What in Ell's name is going on....
Sucked on the booster hose and is free flowing. No noise from the booster... should be a good one but problem is there is no pressure build up when I pump the brake pedal. There are no leaks in the system, resevoir remains constant. Inside wheels are dry. Hoses to the MC are tight, no leaks at any of the conections...as mentioned the resevoir is not going down.
Frustrating nice warm sunny Sunday as I should be driving not wrenching...
Any more ideas out there.?
Chris

[azruss]

sounds like you have air trapped in the MC. I would crack the outdoing lines and pump. Guess it is possible your new MC is bad. Hows the check valve in the booster line.

[SLOSpider]

Even though you bench bleed the master, did you start the bleeding process at the line that connect to the master? I start there and then to the rrr, lr, rf, lf calipers as I bleed. If the rod is adjusted correct then you still have air in the lines that need to come out. Do you have a helper? using those self vacuum bleeders are horrible and better to have a helper so you can see the fluid and pressure coming out as you bleed.

[narfire]

I'll crack the lines at the MC and start there. Then at the calipers with the weight on the axles. RR, LR, LF, RF. I'll get the better half to help as both the vacume thing and although I have a Motive brake bleeder, the thing does not seal on the resevoir and leaks or pops off after a few pounds pressure.

[narfire]

Bled the fronts tonight with the better half pumping the brake pedal. She had the requisite glass of wine in her hand so was not too much of an issue
The brakes firmed up and when I took it for a spin, brakes were way better.
HOWEVER another issue... when I started the car and pumped the brakes my wife could hear an intermitent hisssss....
I pulled on the pedal and it stopped and when the engine was reved up it went away.... pooched booster???

[SLOSpider]

Some hissing sound is normal when pressing the brake. you dont want a constant hissing when you not though. Did you check the rears too? If not get another glass of wine and get to it.

[narfire]

Thanks SLO..
I have to re-adjust the acorn in a bit. I think it is out too far and the brakes are dragging a tad. The acorn should be about 1 mm proud of the face of the booster and I think is a bit more than that right now. Perhaps that is why I hear the hissss, but it goes away when pedal pressed.
I'll do the rears tonight. No shortage of wine here...grow my own grapes..
Took the car to work today with a couple of dogs as passengers, ran pretty good but noticed a bit of a miss and has a high idle.

[courtenay]

Get that little puppy in shape, Chris. Fathers' Day is approaching and if the forecast is decent, I'm planning on coming over...
Cheers,
Bruce

[narfire]

Thanks Bruce.
Think the brakes are more or less sorted. A few more drives will confirm.Perhaps another round of bleading will help. Changed the AFM to another I had and got the idle re-set and is now idling better. The other had a sticky door and I sanded it to let it open smoother but might have sanded a bit too much
Still has an intermitant "miss" when at lower rpms. Fine when accelerating but cruising at 3500 rpm the car will "lurch" like there was an momentary loss of fuel at an injector... no deviation in the tach on the dash.. Wonder if air is getting into the system after the afm? Will check for the 4th time with the propane method today at work.
These cars can test one's patience...
Chris