My First Deuce. Brake issue.

[swindad2]

Just bought my first deuce, a 1969 m35a2, so I have a lot of learning to do. The only complaint is that my brakes are REALLY soft. To the point that last time I drove it, I wasn't sure it would stop. Did notice that as I braked harder, just before coming to a stop, the truck would throttle up a little under hard brake pressure. I have good air pressure and don't hear any air leaks. Where should I look first? The air pack? Previous owner just purchased the kit and included it in the sale. Thanks ahead of time for any input.

 

[goldneagle]

I think you answered your own question. Hint: Something included with the purchase.

 

[welldigger]

If you have a soft pedal then air is being introduced into the brake fluid. If the previous owner included an air pak rebuild kit then as goldeneagle said that's a good place to start. While your at it pull the rubber boot back on the master cylinder and all 6 wheel cylinders. If there is fluid behind the boot then that part needs to be rebuilt/replaced.

 

[Heavysteven]

Inspect your brakes system. Then I would adjust the brake pads and power bleed the system.

 

[shenkmen]

Just bought my first deuce, a 1969 m35a2, so I have a lot of learning to do. The only complaint is that my brakes are REALLY soft. To the point that last time I drove it, I wasn't sure it would stop. Did notice that as I braked harder, just before coming to a stop, the truck would throttle up a little under hard brake pressure. I have good air pressure and don't hear any air leaks. Where should I look first? The air pack? Previous owner just purchased the kit and included it in the sale. Thanks ahead of time for any input.

Read the TM's and inspect every part of your brake system. Your deuce has a single circuit brake system which means one leak will cause the entire system to fail. The TM's have a troubleshooting section. Follow that. Learn the brake system from the TM's then inspect yours.

 

[wbdisco]

Larry,

The brakes have always been as you described them. Even when i bought the truck i took all the brake drums off and inspected all the shoes and cylinders. I also adjusted some of the shoes themselves. I had never been able to lock the tires while stopping, but always could come to a stop while giving myself plenty of room for the cars ahead of me. Also the airpack rebuild purchase was for a gasket leak, I could not find anywhere that sold the gasket by itself.

 

[porkysplace]

Larry,

The brakes have always been as you described them. Even when i bought the truck i took all the brake drums off and inspected all the shoes and cylinders. I also adjusted some of the shoes themselves. I had never been able to lock the tires while stopping, but always could come to a stop while giving myself plenty of room for the cars ahead of me. Also the airpack rebuild purchase was for a gasket leak, I could not find anywhere that sold the gasket by itself.

There definately a issue with the brakes that needs to be addressed . Air in the system , rubber brake lines swelling , by passing in the master cylinder and a lot of other possibilities but as it is the truck is not safe for the road.

 

[swindad2]

Should there be any kind of air sounds with the air pack. Like the sounds modern air brake trucks make, or is the air pack system silent on these. I hear no sounds when pressing the pedal. I read another thread somewhere on this forum about a sound pressing the brake with the engine off.

 

[welldigger]

When you release the brakes you should hear air releasing. When I bought my truck the air pak was locked up and it hissed continuously when I pushed the pedal. Installed a brand new air pak and I can lock up all six and leave one heck of a skid mark. Your symptoms sound like the seals around the shaft of the air pak are bad allowing air into the brake fluid. If I had to put money on it id say the air pak needs a rebuild or replacement depending on how bad the corrosion is on the air side.