Brake question M989 Trailer

[WPNS421]

I recently got a m989 trailer and am having trouble comprehending the brakes on the trailer. I hook up my brakes to the truck M35 and hit the pedal once or twice but the brakes are locked. On the front of the trailer there is a push lever and once you play with this the brakes unlock and the function normally. How or what does that push knob do???? I tried looking in the specs sec tion but it will not let me in. Could someone who knows tell me the hookup procedure. Thanks.

 

[frodobaggins]

You turn on the valves on both sides of the truck ?

 

[WPNS421]

Yes both valves on the truck were turned on and I also check to make sure I did not have the hoses on backwards. It's the little knob on the front that is throwing me for a loop. It says on the plate "Push to release brakes"?????

 

[jasonjc]

Its like a parking brake, I belive.

 

[Nonotagain]

I don't know if the USG will allow you in but in case they do, try this link.

https://www.logsa.army.mil/etms/ind...fb79777d9-54A82AC7-E5D8-BB34-BD9B2D47246FE3C3

If you get in, enter into the pub title section "M989" and life will get better.

If you still have problems accessing, PM me your e-mail addy and I'll send you the two manuals that I have.

 

[jaxsof]

It is a straight "air brake" trailer. That is most likely a parking brake -releases air from the spring chamber applying the parking brake (straight air brakes usually have at least one axle that will apply the brakes in the absence of air, preventing a roll-away)


Nice Trailer!

 

[Jersey4x4]

How about the front glad hand vent. I believe it is the starboard front glad hand, it should have a vent in the cap to allow air back out and if clogged it will cause the brakes to stick. It wont let the air out of the trailer brakes if the vent is clogged.