Car sat for about 6 years in an unheated garage...Master Cylinder was shot. I installed a new 17MM ATE master cylinder. Brakes have been bled twice using the helper system (pump...crack bleeder valve while holding petal down, close, repeat). I connected a clear plastic hose to the bleeder nipple and saw NO air bubbles the 2nd time around (and very clean fluid). Plenty of fluid in the reservoir. Used DOT 4 fluid.

Pads and rotors all look good. Emergency brake system works very well.

I spun each wheel and had someone hit the brakes to confirm that the calipers were not siezed.

Took the car out a few days ago and hammered the brakes from about 35MPH several times. There was no pull in either direction. The brakes were reasonably effective but seemed a little sluggish. Does it sound like the calipers should be rebuilt?

I am not sure what I should expect with a 36 year factory brake system and my expectations may have been set too high

Any suggestions before caliper rebuilds would be appreciated.

Thanks,
Bob

you missed a bleed point you have to bleed the proportioning valve... it's a bitch, it sucks, but no worse than changing the god forsaken M/C. if the brakes were in decent shape when parked in a garage, then they will probably still be fine. drive it a bit, gingerly, then bleed again and again until the pedal is hard.

if you stopped without drama, your brakes are working. if you SLAM on the brakes they SHOULD lock up. a few stops should shed any surface rust the rotors had off...

also the rear brakes do not self adjust, you need to adjust their venting clearance manually.

.008" vent clearance.

I would be wary of the rubber lines as well, but they are not causing you any issues at this time. They are old, though.

I know the books say 0.008" clearance, but I have been much happier with 0.004" myself. And a few others around here (I think Cap'n Krusty and Eric Shea, to name two) agree with me on this.

--DD

Porterfield pads helped my re-built system feel more effective.

I think I split the argument and went .006 so I only need 1 feeler gauge

Cant argue with Eric, he is the brake caliper king

Cap'n Krusty 'says' that the factory instructors admitted the 0.008" was in error in the factory literature, but it never got corrected. So 0.004" it is.

You probably have crappy pads.

Drive the car around for a while and get the bubbles out of the rear "Pressure Regulator" (my fingers know how to type "there is no proportioning valve on a 914" automatically now.)

Re-bleed the rears and try to reseat the pads.

Check this out:

http://www.pmbperformance.com/page/page/1492423.htm

If they don't get any better, scrap them and get some real pads. Porterfield R4S pads for that car will run you $125.00 bucks. That's the best and least expensive brake upgrade I know of.

If everything is braking evenly and there's no stuck pistons you should be good. Sitting 6 years is never a good thing for the brakes and, you may want to eventually invest some time in rebuilding the calipers.

Good luck.

E.

There is a nice piece on caliper rebuilds in Excellence, April I think.

Thanks for the helpful info

Will the fluid work the air out of the proportioning valve just by bleeding the rears after driving or do I actually have to crack a line at the proportioning valve?

The master cylinder swap was an adventure...getting those lines in the top in that limited space was a good time!

Will check the venting clearance on the rears as well.

Bob

Great article on breaking in new pads.

I bet crappy pads are part of the problem, because the brakes are reasonably effective.

I appreciate the info.

Bob

you gotta crack the line a little to get the prop valve to bleed. after doing that, I re-bled all 4 wheels, too

Were the hoses changed? They can play a major factor.