Can u bleed brakes with no power?

[weever82]

All my brake lines, master cylinder, pads, shoes, etc... Have been replaced and ready to be bled. I have no power hooked up yet to the truck, can I still fill the master cylinder and bleed the brakes or have to wait until I can turn the key for accessory power. I have power brakes and discs up front.

Thanks for help!

[GASoline71]

No power needed... Bleed away!

I would do a gravity bleed if everything is brand spankin' new. So that way you're not pumpin' the pedal for a week to get fluid to the ends of the lines.

Then bleed normally.

Gary

[weever82]

Great! I don't have my radiator, dash gauges, etc... installed back in yet but didnt want to leave these half done. Thanks for the heads up!
Posted via Mobile Device

[weever82]

Originally Posted by GASoline71

No power needed... Bleed away!

I would do a gravity bleed if everything is brand spankin' new. So that way you're not pumpin' the pedal for a week to get fluid to the ends of the lines.

Then bleed normally.

Gary

I was thinking the same thing.... But my wife is doing the pumping and she hasn't been too nice to me lately so we will see.... Haha!
Posted via Mobile Device

[DesertCat]

Originally Posted by weever82

I was thinking the same thing.... But my wife is doing the pumping and she hasn't been too nice to me lately so we will see.... Haha!
Posted via Mobile Device

I'm gonna be needing my brakes bled too, probably Tuesday afternoon. Just sayin'

[jocko]

recommend bleed the master cylinder separately to get the air out of its circuits. (usually before it's installed, or via recirc tubes into the reservoir, etc - personally, I normally follow the instructions that come with a new mc to get the air out of em - they usually come with plastic plugs that eliminate the need for the recirc tubes - be careful to only push the mc piston in and out as much as the directions - usually just about an inch. More will induce air). If you don't, just bleeding via the pump (and gravity) method won't get the air out of the master.

[GASoline71]

I should have mentioned that the master cylinder should be bench bled.

Notice I said should... I have gravity bled systems before and not had to bench bleed the master cylinder. But it's common practice to bench bleed the Master cylinder first.

Gary

[TBONE1964]

Originally Posted by GASoline71

I should have mentioned that the master cylinder should be bench bled.

Notice I said should... I have gravity bled systems before and not had to bench bleed the master cylinder. But it's common practice to bench bleed the Master cylinder first.

Gary

^3 you will never get all the air out unless you bench bleed the master cylinder.

[weever82]

Can someone school me on how to bench bleed? I got no instructions with the M/C but came with some plastic tubes/plugs. Already hooked it up, how to bleed that way?

Thanks guys... I'm still learning
Posted via Mobile Device

[TBONE1964]

Did your new master come with a kit in a plastic bag that would contain a couple of plastic fittings and some short pieces of tygon tubing?

This is a cheap throw in bleeder kit. The idea is to clamp the master in a vise, thread the fittings into the ports and attach the tygon tubing into the fittings and then place them into the master cylinder. make sure the ends of the tygon tube stay submerged in brake fluid. Then fill the master with fluid and use a medium to large size phillips screw driver or something similar and push the master cylinder piston all the way in and release until you do not see air bubbles. You can use regular flared steel brake line to do this also. There should be instructions with the master on how to do this.

When you try to bleed a master on the truck, you cannot get the piston all the way to the end of the bore. That is why bench bleeding is needed.

Hope this helps and yes you need to remove the master cylinder to do this correctly.

[jocko]

when you bench bleed, I do not believe you should push the piston all the way in - only approx 3/4 to 1" in and that's it. Slow and easy for a good number of reps.

The way I ensure I don't push it too deep is to place whatever tool you're using into the mc piston bore and mark the tool where it is flush to the back of the mc (or some reference point on the mc). Then I wrap blue painter's tape an inch further up on the shaft of the tool (screwdriver, sharpened stick, whatever) and then push the tool in and out up to the point where it ALMOST reaches the blue tape - that is how you can ensure you are not pushing it in too far.

Also, be careful putting the mc in the vice, you can easily crack it if you whang down on it too tightly. I normally fill it half full and just cradle it in my left arm while I stab it (gently) with my right.

Also, if your kit has the PLUGS, you don't need to use the tubes, simply install the plugs and cycle the piston as mentioned above. remove the plugs and hook it up to your lines.

As Tbone mentioned - you should remove it to bench bleed it.