M35A2 Brake Trouble.

[helobravo]

First of all, thanks Timntrucks for the use of his gigantic impact wrench!

I have finally got around to repairing the brakes on two dueces I am selling soon.
I have a 1958 (I believe Tim posted about it with some pics somewhere) that just needed a wheel cylinder rebuild. It was stopping fine before I parked it.

My problem is late 70's model. While bleeding the brakes, with the air system charged, it sounded like a horse snorting under the truck when the pedal was depressed. We bled it anyway and after that we noticed brake fluid under the truck from the air boost/mastercylinder area.
It was everywhere...on top of frame rail and bottom of floor board even. There is no way to narrow down where it's coming from even looking while pumping pedal. The pedal got hard as a rock also.
ETA: The mastercylinder has a breather line that attaches to the top. I am under the impression that that is just a breather, but if not, it was disconnected while bleeding. I've left the cap off the master cylinder every time I've bled my other dueces with no trouble.
Is the "air boost" the notrious air pack? If so, there's a rebuild kit, right? If not, what's the deal.
Thanks in advance.

 

[dabtl]

Do not be afraid to rebuild the airpack. Just get the kit off eBay fairly cheaply and follow the TM instructions. All you need is a small brake cylinder hone and some patience.

The only problem I found was the piston cylinder end gasket was too small. Make another with gasket paper from the hardware store.

Look up the rebuild threads here for really good advice.

 

[Somemedic]

When you pump the pedal with the lid off the master cyc, as you let off the pedal and JUST start to push on the pedal again, sometimes the master cyc "burps" and it will shoot a little bit of fluid up and out of the cap hole. I'm not saying its a jet but it has shot up and onto my floorboard. It usually coats the MC and parts in the near area. Not sure this is what's supposed to happen but its what I've seen first hand.

 

[helobravo]

Right. I have witnessed "burps" on other vehicles. Just wanted to add the bit about the tube/cap.
This wasn't a burp. This is a hose down.....
Can some one verify for me that this type/amount of "leakage" is what happens when an air pack goes bad?
What happens when an air pack goes bad?
Thanks for any replies.