deuce brake work

[BFR]

I am about to rebuild/ replace all 6 wheels cylinders and replace all the soft brake lines on my deuce. I plan on doing it in stages (one axle at a time) will I risk damge by removing all brake fluid then leaving the sytem "open" untill I finish (a couple of weeks)?

 

[whistlingdeuce]

I think I would leave as much of the brake fliud in as possible unless you are flushing the system. I know that DOT3 brake fliud attracts moisture that is y you have to use it from a sealed container. I don't think that DOT 5 does much better. I could be wrong. I was thinking that the 5 does good againist water that is y they use it for stuff that sits a lot. but now i have really confused myself. to be on the safe side i would leave the fliud in it and top off and bleed when you are done. I am in the middle of doing mine now. it is a little pain but hopefully it will stop when i get done. sorry if i confused you more than what you were to begin with.

 

[Recovry4x4]

DOT 5 will not attract water (not Hygroscopic). I still wouldn't leave the system dry unless I had to. If you are replacing all the rubber lines here's what I would do. Clamp off the rubber lines front and rear and do all your wheel cylinder work to completion. Upon completion of that stage I would move to the brake hoses. Do the front ones at one time and seal it back up then do the back ones at one time and seal it back up. You would probably be OK but I just don't like leaving the system open.

 

[acetomatoco]

Close the system between steps.. by sealing all open lines and the MC cap vent and so forth...changes in atmospheric pressure and humidity migrate water to all the places you do not want it... hang a old wheel cyl on the wheel brake line etc....

 

[WOLFMAN1]

WORKING ON BRAKES ON MY DEUCE, I HAVE A PROBLEM MYSELF, MY FILLER CAP ON THE MASTER CYLINDER HAS A FITTING TO A HYDRULIC TUBE. THE TUBE IS MISSING AND I DON'T KNOW WHERE IT RUNS TO UNDER THE TRUCK. IT IS AN OLD 52 DEUCE AND DONT KNOW IF THE CAP WAS REPLACED WITH SOME OTHERONE. NEED SOME HINTS

 

[bigtoyman]

probably a vent line, should be a line with a T on the frame crossmember nearby that it is supposed to hook into........

 

[WOLFMAN1]

AND WHAT ELSE WOULD IT HOOK TO. IF I PLUG THE CAP WOULD THE BRAKES STILL WORK. CAUSE I SEE SOME BRAKE FILLER CAPS THAT DONT HAVE HYDRULIC HOSES COMING FROM THEM

 

[bigtoyman]

Not aware of any other possibities unless it was a remote brake fluid reservoir.
Brakes would work if opening is capped but run risk of pressure building up in master cylinder and blowing a seal if there was no pressure relief, if left open it will get dirt in master cylinder which would seem undesirable...

 

[USAFSS-ColdWarrior]

subscribed....

Good thread and worthy thoughts before I set in to doing a similar project.

T H A N K S

 

[WOLFMAN1]

THANKYOU BIGTOYMAN, DOES ANYONE ELSE HAVE A SUGGESTION ON HOW TO CAP OFF MASTER CYLINDER FILLER CAP AND BYPASS PRESSURE IF IT SHOULD BUILD UP. I WAS GOING TO CAP IT OFF WITH A STUD BOLT MADE FOR HYDRULIC LINE FITTINGS AND HOPE FOR THE BEST. I THINK I FOUND THE T JUNCTION SOMEONE MENTIONED EARLIER AND IT HAS A BOLT IN IT. IT WAS LOCATED ON THE CROSS MEMBER BEHIND THE MASTER CYLINDER AND AIR CYLINDER.

 

[rlwm211]

I would find the appropriate fitting to install a rubber hose and run that up and inside then body of the truck. You can put a t in the top, or simply make a loop so the open end is down. All the small fitting in the top of the master does is allow air in and out. You can find vent tips that hve small screens in them that are used in automotive applications.

If you look around, you should see a copper line running from the airpack, the big brake booster which is downstream from the master cylinder, to the air cleaner housing. That is normally where the air vent is tied into from the master cylinder.

I just did a complete brake rebuild on my truck, including new wheel cylinders and master cylinder and I rebuilt the air pack. I bled the truck myself without the "pressure bleeder" that some use and had no difficulties. I will keep tabs on this post and any help I can offer I am happy to do so.

RL

 

[WOLFMAN1]

THANKYOU I WILL TRY THIS AND SEE IF IT WORKS, WHERE EXACTLY DOES IT CONNECT TO THE AIR CYLINDER, OR WHERE IS THE AIR PACK THAT YOU TALK ABOUT. WHAT SHOULD IT LOOK LIKE

 

[bigtoyman]

might be more funner for us if you can take some pics of undersurface of truck near master cylinder. believe just below and medial to master cylinder. All kinds of cool stuff under there, I usually will test for loose bolts and fittings etc by banging different parts of my head against them (then I'll get something in my eye if I'm dedicated)

 

[rlwm211]

I you have located the air pack, its the large device with what is called a "J" pipe connecting the end to the control body. you will notice that there is a hydraulic line connecting the master cylinder to the air pack and a hydraulic line running from the air pack to the truck. There is also three air lines. These are much bigger tubing. One is the air feed and runs from the air pack to the air tank immediately behind the air pack along the same side of the frame. Another runs to the rear of the truck to the "service" aglad hand air brake connector on the back. The last is the exhaust line for the air pack and runs up and accross the frame and towards the air filter assembly. It is possible your truck does not have this line or it is routed to another location. This "exhaust line" is where the master cylinder is normally vented via a "TEE" connection.
The air pack usually has a skid plate mounted on the bottow which protects the various lines from damage from brush and other items you may run over.
If I get a chance, I will take a photo tomorrow morning.

RL