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Brew
Did I miss something?

I changed out my old MC for a new 19mm per the Pelican article, and changed out my soft lines while I was at it. I've bled all 4 corners with a vacuum pump, but the pedal still goes to the floor. I cant get it to pump up at all, even depressing it multiple (~50) times.

Help?
Dr. Roger
i wouldn't use the vacuum pump eventhough many do.

i use a buddies foot and my tubing wrench. never fails. =-)
bd1308
Got fluid in the resivour?

I lost my brake fluid three times in the little tank and was STILL able to get it bled within 50 presses

Sounds like you still have a ton of air in there. Plus did you start from the back and go to the front last?

plus the proprtional valve traps air too.

b
john rogers
It sounds like you have air. If you do not have a pressure bleeder then the two person method is the only way to go. Make sure to top off the res. then crack the lines at the m/c to let some fluid out to make sure the m/c is full. Then do one wheel at a time making sure the fluid level stays topped off. If you still have the prop valve then bleed the line to it and then the rear wheels so there is no air in the rear part of the system.
Borderline
i've never tried a vacuum system. I bought a second cap for the brake resevour and hooked up a tube connected to my air compressor. I bleed my brakes by pressurizing the resevour with something under 10 psi. It seems to work reasonbly well but I still feel the need to bleed some more the old-fahioned-two-person way. the pressure system is great if I can't get my wife to come down and give me hand. Everything I've read on this board seems to indicate that you just have to keep bleeding the system. I don't know why, but the teener brakes seem to be very difficult to bleed. Try getting an assistant to help you up,down,up,down,up,down..............
Flycut
First thing with Brakes is pad adjustment, Fronts are self adjusting but the rears need to be adjusted on both sides with an adjusting screw on either side of the calipers(venting clearance0.2 in). Pad adjustment is critical to proper brakes, I go by feel and adjust the pads so that if your tire was on you could not spin it 1 full turn if you tried. I always bleed from the farthest point of the master cylinder and so on.
Make sure you keep your resivor full. I use a tube from a bicycle, cut 12 inches on either side of the valve stem and then knot one side. Clamp the other end of the bicycle tube to your resivor and pump that baby up. You can now open the nipples on each caliper and bleed the whole system yourself, Filling the resivor and pumping your innertube as required.
Dr. Roger
i should add....

when i was having issues trying to get mine firmed up someone suggested replacing all my rubber lines and i finally did.
when i did my pedal firmed right up. dang club members... think they are so smart.... LOL

right rear wheel cylinder first.
then left rear
right front
left front last.

have a second person pump, pump, pump, then hold pedal down.
you then bleed valve and close valve.
do this three times then top off MC.

do it again till you get no bubbles and new looking fluid coming out at all 4 corners. some use blue fluid so that they know when all the old $hit is completely out of the system. speed bleeders are pretty cool too. they're gunna be on my christmas list this year.
Brew
Is it not neccessary to bench bleed the MC on these cars? That's the only thing I can really think of doing differently, but it didnt say it on the PP site.
Joe Ricard
Yes bench bleeding the M/C is a good idea. I made up a cool tool.
took the pedal assy from the stripper, bolted to my work bench
got two BMW calipers. (hey I found a good use for them).
I was able to bleed everything and test the M/C.

Funniest thing. I found a bug in one of the lines it was blocking fluid flow to the front port. Nothing an air compressor couldn't fix. That bug hit hyper drive as it flew out the line.
JPB
I just did this and this is the way to go. First, you must start with the furthest wheel from the masterC to the shortest. All need to be "free" of air before ya go to the next wheel. You should get preasure building up as you progress. Once all have been bled, see if the pedal travel is excessive. You need to do this in that order. The most helpfull item to have are speed bleeders. You just crack the valve open a 1/4 turn and pump fluid until the preasure builds up. The front circuit is independent of the rear one so each is bled almost independantly. I had problems with my front calipers because the push rod on the clutch pedal needed to be adjusted shorter. It didn't allow fluid to get into the MC so no preasure was ever built up after the rear breaks were bled. Look for leaks and use speed bleeders if you are alone, they will help you and will be a sinch to bleed them right!

beer.gif Gluck.
Dr. Roger
"flycut" is right on also......

it doesn't matter how much you bleed...

if your venting clearance is excessive you will go to the floor. ask me how i know. LOL
Brew
Thanks all!

I'll mess with it more tomorrow, and be back if I cant figure it out.
PRS914-6
Are you tightening the bleeder screw before the peddle comes up? If not, the air just goes back and forth. Also, use smooth, slow strokes on the peddle. Lot's of people pump the hell out of the peddle and it just makes matters worse by aerating the fluid. After I get the system feeling good and I think I am done, I come back several hours later and bleed one more time. I always get a little more air out after things settle down.....
So.Cal.914
QUOTE(PRS914-6 @ Aug 20 2006, 08:08 PM) *

Are you tightening the bleeder screw before the peddle comes up? If not, the air just goes back and forth. Also, use smooth, slow strokes on the peddle. Lot's of people pump the hell out of the peddle and it just makes matters worse by aerating the fluid. After I get the system feeling good and I think I am done, I come back several hours later and bleed one more time. I always get a little more air out after things settle down.....


Your the first person here I've read that has mentioned going slow with the pedal

so you don't turn 50 air bubles into 500. We learned this at brake and alingment

school but I thought I was the only one that still did it that way.
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