brake problems

[soutimpro]

New to the site and was hoping someone could help me. Just bought a m-49 fuel truck to use at the job and i dont have any brakes. The guy i bought it from told me they didn't work. Tried bleeding them from the screw on the air cylinder(not sure what you call it) but i just keep getting air in the fluid. Not sure how to troubleshoot from here.

 

[73m819]

Does it have fluid in the m/c, if not, fill then pressurize and find the LEAK that you need to FIX.

 

[porkysplace]

Have you downloaded these ? TM's for the Deuce
GTA-9-1-1851-8.pdf this will teach you what parts are called
TM9-2320-209-10-1.pdf should be read before operating your truck
TM9-1827c Ord. Maint. Wagner Lockheed Brakes Manual for repair and maintenance of Hydraulic brake systems illustrated
TB-9-2300-426-20Hydraulic and Air Hydraulic Brakes preventive maintenance Includes important information!


TB43-0002-87 BFS Brake fluid replacement procedure

 

[soutimpro]

we filled the m/c with dot 5 before we got started. whats the best way to pressurize the m/c?

 

[doghead]

You need to bleed the air pack, then the wheelcylinders.

If you are getting air at the air pack, you may have a bad Master Cylinder.

Pull the boot on the push rod and see if it is wet or leaking as you pump it.

You need to be sure the two little holes at the bottom of the master cylinder are not pluged with rust.

Pressure bleeding works well. Search power bleeder.

You need to be sure what brake fluid you have, as you cannot mix them. The military uses dot5.

 

[soutimpro]

i used dot 5 fluid but when i was going through the truck i found a container of dot 3 fluid that had been opened so i'm assuming someone has put that in the system

 

[doghead]

Well, let me ask you this, what is your goal with this truck?

Do you need it to be safe and reliable?

If it were mine in this situation, I would flush all lines and do a complete brake system overhaul(rebuild or replace everything(except the steel lines). Maybe even the steel lines if any look rusted.

 

[soutimpro]

the truck will be used on a logging job to fuel equipment. it will never be used for on road purposes but i still need some brakes on the truck especially when i load/unload from the lowboy

 

[doghead]

ell, you can start with a good bleeding and see what you get. Watch for "gelled" brake fluid(indicating a mix). Mixed fluids tend to destroy the rubber in the system.

You can remove the vent on the master cylinder and screw a pipe nipple into that hole to pressure bleed the system with a home made power bleeder. You can make one from a garden/lawn sprayer.

We have a thread on the site explaining how to make one.

I would bleed until clean purple fluid comes out of each bleeder.

 

[doghead]

Here is the thread for the power bleeder.

http://www.steelsoldiers.com/showth...er-Bleeder-R4x4-Style&highlight=power+bleeder