No Brakes!

[blackxj]

Tried search, but no info? Picked up a deuce today. No resistance on brake pedal at all. Fluid was low, filled to top and still nothing? air in system? Need to be bled? Please help............

 

[Goose2448]

Make sure there is no leakes anywhere. The wheel cyclenders can go bad, lose one and you all the brakes. Also check to make sure there is air. If there is no air, the brakes should still work.

 

[roscoe]

Need more information. Air guage working? Compressor running? Try bleeding the brakes? Did you use DOT 5 fluid? Leaks?

 

[hndrsonj]

Read the manuals in the resources section, add DOT 5 fluid, bleed according to the manual, check VERY good for leaks. That just gets you started. You need to do a very thorough inspection of the entire brake system before you drive it.

 

[stumps]

Tried search, but no info? Picked up a deuce today. No resistance on brake pedal at all. Fluid was low, filled to top and still nothing? air in system? Need to be bled? Please help............

First thing to do is to bleed the brakes. A pressure bleeder made from a cheap pump up garden sprayer works wonderfully! There is plenty of info in back posts on this site on how to do that.

In capsule: You have to bleed the master cylinder first. That is done by filling it, and pumping the brake pedal slowly, and repeatedly down to the floor and back until it stops bubbling in the master cylinder's tank. (I am assuming that you know how to bleed brake systems manually... if not ask.) Once that is done, you need to bleed the air assist unit, and then you go to the furthest rear axle and bleed both of its brakes... one at a time, of course! Then the middle axle, and finally the front axle.

It can take a while for air introduced at the master cylinder to reach the rear of the truck, so bear that in mind.

Now, the big question is why did your brakes go soft? From my experience (limited), and the testimonial of others, I believe that most deuces have a one way valve vent on the master cylinder cap. That vent allows air to leave the master cylinder, but does not allow air to come back in... and that is a big problem! When a deuce sits, the temperature of the air cycles hot and cold. When it is hot, air leaves the master cylinder. When it gets cold, the vacuum that results sucks air in through the weakest wheel cylinder. The wheel cylinder piston cups are designed to push, not pull. The seal has very little resistance to suction.... almost none.

You will need to determine why your system leaked, but most likely you will find, like many others, that once you bleed it, and use your deuce, it doesn't happen again.... until you let it sit for a long period.

-Chuck

 

[blackxj]

compressor is working, air gauge is building to full, truck has been sitting for a couple of years, fitting in master cylinder fill plug appears to be broken(can blow freely from either direction), filled with auto brake fluid(is that DOT 5?), haven't found any leaks, know how to bleed auto system,where is bleeding procedure on forum? Thanks, Guys

 

[rmgill]

Once you think you have them sorted out, drive slowly to an area where you can test the brakes. Stand on them HARD. Then slowly drive forwards or backwards where you have some slowing room, accellerate and then stop HARD. Do this a few times to REALLY test the system. See if all wheels are really locking up. I did this with a M818 that I fixed the brakes on (busted front line from a careless wrecker driver, I could see the clamp marks around the axle).

 

[roscoe]

compressor is working, air gauge is building to full, truck has been sitting for a couple of years, fitting in master cylinder fill plug appears to be broken(can blow freely from either direction), filled with auto brake fluid(is that DOT 5?), haven't found any leaks, know how to bleed auto system,where is bleeding procedure on forum? Thanks, Guys

What Stumps and others said. Probably not the correct brake fluid. Should say DOT 5. They don't mix. Keep us posted.

 

[Keith_J]

Sure sounds like the situation Chuck (stumps) illustrated. When all 12 (yes, a dozen) of the wheel cylinder cups retract a fraction of an inch, the displacement of the master cylinder isn't sufficient to force all 12 shoes to contact the drums.

I would recommend getting rid of the breather on the master cylinder cap as this could cause further problems. Replace with a breather line to the air cleaner or booster exhaust. But be VERY CAREFUL as pressurizing the master cylinder with air will cause brake drag.

 

[hndrsonj]

If you just went to Autozone and picked up the cheapest brake fluid, you need to stop and completely drain the brake system and start over. The can will say DOT 5 on it. Like what was said they should not be mixed. The manuals are in the resources section at the top. Look for the 1965 they are about the best ones. They are 4-5 pages into the list.

 

[stumps]

compressor is working, air gauge is building to full, truck has been sitting for a couple of years, fitting in master cylinder fill plug appears to be broken(can blow freely from either direction), filled with auto brake fluid(is that DOT 5?), haven't found any leaks, know how to bleed auto system,where is bleeding procedure on forum? Thanks, Guys

DOT5 is not common automotive brake fluid! It is silicone brake fluid, and is very expensive... unless you buy a gallon from some place like Spruce Mountain Surplus.

If you put DOT3 in your master cylinder, you are going to need to flush your system and either go back to DOT3, or go to DOT5 like the government did. There should be a yellow DOT5 warning label on the floor hatch to your master cylinder. DOT3 and DOT5 are not really all that compatible in the long term.

I would recommend sucking out the DOT3 with a rubber bulb, and if you haven't bled the system yet, remove the hydraulic tube from the master cylinder and flush the master cylinder out thoroughly with DOT5. Then bleed the air assist cylinder with a lot of DOT5, and you should have contained the problem...hopefully.

The Government switched over to DOT5 for two reasons, the first is it doesn't support rusting in infrequently used vehicles, and the second is it behaves better in the high temperatures that can live in truck brake drums under heavy braking.

-Chuck

 

[blackxj]

Does anyone know the number to the manual mentioned above? I'm really trying here........My eyes are crossing looking at manuals My slow connection is not helping either

 

[JAYHAWK 1962]

Hey blackxj. Do your self a favor and buy or make one of the pressure brake bleeders. There is a previous post on where to buy and how to make an adapter has pictures of items you need at home depot. If you only use it once it is the best 50$ i have spent in a long time. Had 3 trucks little to no brakes. Had all three bled and good to roll in 30 minutes total. Look for the dot 5 (purple stuff) on the surplus or e-bay market about 30 bucks a gallon. Hope all goes well.

 

[nk14zp]

I use dot3 in my truck.

 

[SCSG-G4]

If you put DOT-3 into the system, might as well purchase a gallon or two of DOT-5, because it may take that much to fully bleed the system of the DOT-3 stuff. And after you price it in the store, you will wish you had asked here long before your first brake fluid purchase.

 

[atankersdad]

I knew nothing about brakes a year ago. This is my brake bible. It is the repair manual on brakes, a must read... You can download this from the Resource section..

SMARPI-9-2320-209-14

 

[BKubu]

Don't forget to inspect every inch of brake lines for a leak.

 

[stumps]

Underneath the "STEEL SOLDIERS" title on every page, there is a list of places you can go: UserCP, Forum Rules, ...Resources...Quick Links, Logout.

Click on Resources. Select: Technical Manuals, and click on it too.

At the bottom of the page is a navigation arrow that says: "Next Page>>".
Click on it, then when the new page gets drawn, clidk on it again. At the top of the page you will see the manual.

You can also reach it here (I think):

http://old.steelsoldiers.com/index.php?module=pagesetter&type=file&func=get&tid=1&fid=file&pid=85

-Chuck

 

[blackxj]

I found it! Thanks Chuck! now, off to find thread on hm bleeder!