Airpack install ?

[Marks Garage]

I got a brand new airpack today. I had one of my techs pull it off and he let the master run dry. We lubed it and installed it. No pedal. I bleed the air pack but I got to get the air out of the master first. What is the best way? Do I bleed the master,airpack,wheels starting in the back in that order. Thanks guys. Mark

 

[ken]

I bleed at the front of the air pack first. then at the wheels

 

[Marks Garage]

What about the air in the master?

 

[Recovry4x4]

I bench bleed my mastes when I install them but do it on the truck. You can reach up from underneath and bleed it by pulling down on the pedal arm.

 

[Marks Garage]

Whats the proper procedure to bleed the master on the truck? Pull the line and hold your finger over the hole?

 

[Loose Deuce]

Can you just crack the line coming out to bleed it? Why dont they have a bleader valve anyway ?

 

[MVtrucker]

Bleed it at the booster (air-pack).
I'll add that I mount the master cyl. in a vise, put fluid in and work the

piston in it to get most of the air out before I install it.

 

[Loose Deuce]

Hey Joe, I understand about doing it on a bench or vice when installing one but if your master cyl has leaked dry and you think it may need bleading what then? Most cars and trucks have a bleader valve on the myster cyl. I understand about starting with the air pack first also.

 

[MVtrucker]

I've never met a master cylinder with a bleeder on it. Okay, here's what to do: About 3/4 fill the master, then make a lot of slow short pumps on the pedal. Leave the lid off so you can see the bubbles on each stroke. Do not press far because that would force air further into the system. A lot of times you'll get some pedal (I hope you know what I mean) by doing this. If spongy, proceed to bleed the air pack and the wheels. Yes, after the pumping, you can crack the line and push the pedal, but I think you'll get that air out at the pack's bleeder.

 

[Recovry4x4]

Here's how I do it right or wrong. Once the master is installed on the truck but before the brake line is installed, I screw in a plastic fitting and a piece of hose. I then run the hose into the top of the master cylinder keeping the end submerged in the fluid. I then slowly SLOWLY work the pedal up & down from underneath. Once completed I install the line and move my bleeding to the airpack, then the wheels.

 

[cranetruck]

The bleeder valve on the airpak bleeds the mc. Do that first, then go to the wheels. The way I see it, it doesn't matter in which order the wheel cylinders are bled, each is independent of the other.