5 ton issues

[Rolling Thunder]

a. Motor starts, runs and soon as i put it in a forward gear it dies, hard stop. when i first got it the brakes locked up and i caged them today but still does the same thing with one added oddity now, reverse doesnt want to work or work when it wants.............help.

 

[armytruck63]

Which 5-ton? If it is the M939 series, maybe the lock up torque converter is staying locked and causing the engine to stall.

 

[MtnSnow]

As for the brakes....Are you waiting for the system to build at least 60 psi in both the primary & secondary air systems? Is the truck building air?

 

[Rolling Thunder]

Sorry should have put that in first post. .MY Division of Harsco M923A2 5-Ton Cargo Truck w/ a 14-Foot Dropside Cargo Body. Yes sir on the brakes she builds up great solid and fast, on both tanks primary and secondary. When im on the pedal it builds up to close to 120 psi and then the safety valve will release, so i know this portion is working properly. Now is the pressure getting all the way back to the rear brakes that i dont know.

a. If i caged the brakes it should be able to roll free correct? How would i test to see if the correct air pressure required is getting to the back brakes?

b. If its tourque converter how do i discover it is the converter any trouble shooting suggestions?

Thanks in advance for your guys help. I love this truck and want to get it working great.

 

[porkysplace]

Sorry should have put that in first post. .MY Division of Harsco M923A2 5-Ton Cargo Truck w/ a 14-Foot Dropside Cargo Body. Yes sir on the brakes she builds up great solid and fast, on both tanks primary and secondary. When im on the pedal it builds up to close to 120 psi and then the safety valve will release, so i know this portion is working properly. Now is the pressure getting all the way back to the rear brakes that i dont know.

a. If i caged the brakes it should be able to roll free correct? How would i test to see if the correct air pressure required is getting to the back brakes?

b. If its torque converter how do i discover it is the converter any trouble shooting suggestions?

Thanks in advance for your guys help. I love this truck and want to get it working great.

The TM's have trouble shooting sections .
[h=3]TM's for the 939 series trucks[/h]
This one includes wiring diagrams also M939_P2P.zip