The Stovebolt Site Forums The Parking Lot Big Bolts Newbie here, need a little help

I recently bought a 1955 6100 2 ton dump truck. The brakes worked fine when I bought it and for a couple of weeks, I put it in the shed until I had time to work on it and now no brakes. I am hoping it is something simple like a blown line, but where is the master clynder, I looked under the hood and it is not there. Can someone point me in the right direction.
Thanks

It is inside the frame rail. Lift the floor mat on the drivers side. There is a large (about 4" diameter) grommet that you remove to check the fluid level.

bigdonn - just exactly what did you do when you "worked on it"? That would really help the guys to figure it out.

One of those slow leak jobs sounds like. MY 47 was doing the same thing. It would hold brake fluid for about 3 days but after a week the master was empty. Once you locate that master cylinder (it should be under the cab floor attached to the frame as mentioned above) refill it and pump till you get the breaks back (may have to bleed everything but may not too.) Look at all the drums see if the bottom is wet any where (if so you got a slightly leaking wheel cylinder) If not trace your lines check for any lost break fluid. Lines on this unit are simple. YOu have a single line runing from the master cylinder back the left hand frame rail. At the back of the cab there should be a support the break line crosses to the right hand frame rail on this support. At the right frame side of this support their should be a cylindrical thing the line runs into. This is you hydro-vac break booster. (I'll come back to this later)The line then leaves there and splits to the front and the rear running on the right frame rail.
IF you can't find any leaks you probably have a bigger problem...
Let the truck set for a few more days and see if you loose your breaks again. If so your hydro-vac is probably leaking internally. Mine was. I'm currently looking for a rebuild kit but for now I by passed it. Still stops but have to really put some foot into it.
I got by for two years adding fluid every time I drove it cause I didn't want to take apart the hydro-vac unless I knew it was it. Finally got my proof when brake fluid was dripping out of the vacuum fitting on the truck.
Good luck!

Sorry just got back to this post, I did not work on it so much as clean it out and up. No wrench turning!