I’ve had the car on blocks 8 weeks with the brake pedal partially held down to keep from draining the fluid. I installed new rubber brake lines and short hard lines to the calipers, new calipers, new rotors, pads and emergency brake shoes. I let the brake pedal go, siphoned the old brake fluid from the reservoir, wiped it out with a lint-free cloth, filled it with gold DOT 4 fluid and used a Motive Power Bleeder at 12 lbs pressure, air-only. I went around right rear, left rear, right front, left front altogether twice tapping the calipers with a rubber hammer. Made sure there was ample fluid in the reservoir. Seemed like the air bubbles had stopped and the color had gone from ATE blue to gold. I tried to bleed the clutch slave cylinder and found it needed a smaller wrench (7mm apparently) so let it go for now. I have no resistance on the brake pedal, but have not pushed it past half-way down. I’ve pumped it a bunch of times to no avail. No brakes. Any ideas would be immensely appreciated.

 

either air still in their or the seals in the master cylinder.

 

Not sure why you would bother keeping the pedal down if you are doing a fluid swap anyway.
Sounds like you drained your reservoir to dry.
I always leave a bit in there to prevent air from getting in the lines.

 

Not sure what you mean by your statement "used a Motive Power Bleeder at 12 lbs pressure, air-only." What is air-only? When I bleed my system (I also use the Motive Power Bleeder), I put the fluid in the MPB and keep it at about 12-15 lbs. It automatically keeps the reservoir full.

It would seem that if you had a seal problem, you would see fluid leaking everywhere around the MC.

I suspect you still have air in the system.

Good Luck!

Regards,
Jim
'86 Coupe

 

Thanks, guys. A lot of guys use the Power Bleeder dry, it prevents messy cleanup and needing to remove excess fluid from the reservoir later. My reservoir fluid level never went below the low mark the whole time, and I should have mentined that my bleeders are all in the up position. I guess there's just more air and I'll keep trying. Anyone know if I can replace the clutch slave cylinder bleeder with one the same size as the calipers? Not sure I'd want to, though, a smaller wrench is probably going to be a large advantage.

 

Check for leaks, check all your brake hose connections, and then try bleeding it again, and if you still don't have a pedal after power bleeding it again (wet not dry, I've never heard of that and it could be the reason you have no pedal), get a buddy to help you do it the old fashioned way. Just make sure you don't push the pedal all the way to the floor, stick a piece of wood or something under there-if the rubber cup seals in the master cylinder are made to travel further than they normally do (like when you let the pedal go to the floor w/ the bleeder screw open) it can ruin them. If you still can't get a pedal after this, then I'd suspect the master cylinder itself.

As for the bleeder screw on the slave cylinder, do yourself a favor and get a 7mm wrench from Sears or someplace; even if you go through the trouble of finding a bleeder screw that fits that can use a bigger wrench, you will find the bigger wrench won't fit in there up above the tranny, the 7mm doesn't have much room as it is! Also when you fill up the reservior with fresh fluid before bleeding the system, fill it past the MAX mark at first so the the fluid spills over into the secondary chamber in the reservior for the clutch circuit, so that when you bleed the slave cylinder you're not just sucking air, which will leave you w/out a clutch pedal as well!

---

Chris Andropoulos
Schneider Autohaus
Santa Barbara, CA

 

Okay... I have to ask... Are the bleed screws at the top of the calipers?

 

As mentioned before, I have bled my system several times by myself using the Motive system. I have always put the fluid in the MPB container (that's what it's for, plus the the pressure), I believe the instructions that come with it say to do it that way. I have never heard or anyone doing it the way you are doing it. I have never had a mess to clean up. Yeah the res is full, but you take a turkey baster or whatever and remove the excess. No mess. If I were you, I would try it the way it is suppose to be used and see if that may not fix your problem.

 

Thanks for the feedback, I appreciate it. Will report.

 

Keep flushing. When I did my brakes (new calipers all around, new master cylinder, new flexible brake lines, new reservoir), I flushed with the Motive Power Bleeder. Brakes were scary soft first roll down the drive way. Drove a very short little bit, and did a full flush again with the power bleeder (beating calipers with a rubber mallet) and got more air out. I probably put 2.5 liters through the system total.

Brett

 

Thanks, Brett, that's helpful!

 

I tapped and flushed again, about another quart, and I have brakes about halfway or so down. With one pump they pump up. Could this be new calipers breaking in? I'll drive for awhile and flush again. Some folks say to bleed by pushing the brake pedal all the way down to the floor but that spooks me.

 

Der Mond,

You have to exercise the new pistons and seals. I recommend putting the old brake pads (should be worn down at least half way) back in and taking the car for a spin making frequent stops. This will allow for the pistons to be pushed out of the bore. Then change to the new pads and go out for drive and see how it feels.

 

Hi I think that the master is toast usually if in the process of bleeding older systems if the pedel is pushed full stroke any debris in the master bore will cut the seal and then the master wont hold pressure. In normal operation the pedel is not usualy pushed full stroke and so the brakes work well, that is why using a pressurised bleeder is good so the seal to bore is not over done and the pressure is used to move the fluid

 

Looks like Pete Z. was right:
With four days of driving my brake pedal is almost completely normal. New caliper seal break-in, I guess. Didn't hurt to keep flushing, though, I did get more bubbles all the way to the end. But it was repeated use of the brakes that brought the pedal progressively back. I'll flush with ATE Blue and bleed the slave this weekend. Live and learn. OK, I'm calling off the Waaaaaaaaambulance!