bench bleeding a mastercylinder.

[iminsanenutz]

need to replace the mastercylinder on my 91 grand am. forgot exacly how to bench bleed it and the whole procedure.

any help will be greatly appreciated.

[rednotch]

Mount the M/C on a vise by the flange
use the fitting included in each outlet port.
put clear hoses on
Route the free ends of the hoses into an half full brake fluid container.
Fill the M/C reservoir with fluid.
push the M/C piston all the way and hold it in.
Slowly release the M/C piston, allowing fluid to be drawn into the cylinder.
Keep the ends of the hoses in fluid to prevent air from going back into the cylinder.
Repeat until all the bubbles are gone. Occasionally tap the M/C lightly to help dislodge any trapped bubbles.

Be sure to keep the reservoir filled.

[iminsanenutz]

thanks guys, guess im doin this on easter, oh well.. get er doooooone

[iminsanenutz]

im going to plug the lines when i disconnect them to prevent air from gettin in there or ruiening the fluid. will i need to bleed the system reguarlly again once its fully installed since i opened the lines???

[Split-N-It]

Yes,...You need to bleed the lines on the car once disconnected. Start at the longest line and work you're way up to the shortest,...make sure ya keep the fluid in the master cyl at a good level so not to pump air into the lines while bleeding.

[adamsvega]

if you dont have the tubes u can use the caps provided . remove them and fill till it drips out and tilt it up and push /thread the caps in now slow and short stroke it till it stops bubbling in the resivoir . ---good to go !

[iminsanenutz]

well i think one or both of the rear wheel cylinders are leaking air, but def not fluid. because the pedal never gets to firm and when it does it will go to the floor after a few seconds without even opening the bleeders.

i put a master cylinder and 2 fron calipers on it. i think im goin to replace the wheel cylinders and maybe even a new pring kit, they look soooo old.


i will also get the right tubing :doh: