master cyl. bleeding

-
74fldart

74fldart

Well-Known Member
Joined
Apr 13, 2008
Messages
207
Reaction score
1
Location
orlando, florida
hi guys today im working on my project , my goal is to get the master cyl on and bled out. this is a rebuilt one. the car is a 74 dart with power disc brakes. ive mounted the master cyl. but not plumbed it in. i have made up 2 tubes to feed fluid back into the resevoirs . kinda of like bench bleeding but using the pedal to pump it. but i have been pumping the pedal forever now and all im getting is a little dribble from each tube back into the master cyl. is there a trick im missing here. ive tried holding the pedal down for a while, making short strokes, everything i can think of and im not getting anywhere. any advice is welcome
 
I just install the master cyl. to the booster install the lines, filled the reseviors with fluid leaving the cap off and bled the lines starting with the passenger rear, then driver rear, passenger front, driver front. Always adding fluid as needed to complete the bleeding. I had to do this twice, because the 1st rebuilt cyl. that I bought had a defect. My car sat for years and I blew out all the old fluid from the brake lines. It took a little before the fluid started to flow.

Chris
 
make sure the brake pusgrod is long enough to completely compress the master cyl. piston... you might have to bench bleed it the old fashion way to completely compress the piston.
 
ok, thats what i thought about doing . tommorrow ill go and try it by hand mounted in a vise i guess.
 
xwaynestaticx03 said:
make sure the brake pusgrod is long enough to completely compress the master cyl. piston... you might have to bench bleed it the old fashion way to completely compress the piston.
Click to expand...


looked at my install instructions and it says to bench bleed it with no more than 1 inch strokes
 
Put it in a vise, preferrably outside, fill with fluid, stick a screwdriver in it and push. As far as it will push, 6 times, or until you stop seeing bubbles inside the mc, with refills, and that's it.

Another trick is after the whole thing is together, is to press the pedal, and crack the lines going to the MC. Always seem to have the last bubble there.
 
Another vote for bench bleeding it. I like the control you have on the bench, and the ability to see if the bubbles have stopped. I would bleed the whole system once you get the master bled. That way you know there's no air in the WHOLE system, plus you get all that old fluid out of there.

I have never heard of using 1" strokes, but I never read the instructions either!
 
When its a new master cylinder full strokes shouldn't hurt anything but...
a used master cylinder hasn't seen a full stroke in a long time. Where it has stpped short repeatedly will probably have a ridge of wear and debrie. Pushing the piston through that can ruin the seals.
I'm gonna try to describe my lazy method of bench bleeding.
Unit is hung in the vise clamping one bolt ear. I've got a 10 inch piece of 2X4 with a 1/2 inch hole drilled about 1/2 way through. Try to picture a bundle of shop rags against my chest followed by the 2X4 then a long tapered punch.
I can grab the vise with my left hand and just lean in. Body weight, leverege, whatever, gives me complete control of stroke speed and depth.
 
You must log in or register to reply here.
-

Back
Top