936a2 air valve question

[shootist]

I've been through the TM schematics pertaining to the air system
and unless I'm blind I can't find what this valve is called in order to
replace it. It mounts behind cab on the A2 crane truck or wrecker if you prefer
its venting air constantly from my secondary tank
oddly enough when messing with the service air connection in rear
i noticed it stopped leaking, but started again an hour later
also if I hit the brake release in cab (under steering ) that will vent and the valve I'm asking about will stop venting
I thought it had something to do with the pto lever

 

[M35A2-AZ]

That is the PTO Control Linkage valve.
When you engage the PTO on the transfer case it locks the brakes.

 

[shootist]

Thanks for the name
having a heck of a time searching for one.
i have to see if I can locate the NSN or general part #
for one

 

[M35A2-AZ]

I looked and I can not find it in the parts TM also. I found the pto linkage parts, but no valve.

 

[shootist]

Same here. Makes no sense.
so... The leak is through the vent cap....
I'm wondering for the sake of just doing it...if I put a 1/4 pipe plug in place of the vent to stop the leak
what would happen...obviously the leak would stop but would it create another situation

 

[Suprman]

Gotta be a special tm section for the wrecker since some of the workings are different.

 

[shootist]

Yeah, went through that to Will.
air schematic is same
if not to cold tonight after work I may try to pull it off
to see if there's any O rings inside.

 

[Suprman]

Luckily I havent had to fix anything odd on my wrecker yet. Probably because I dont do any real work with it though.

 

[shootist]

Ok, so after fighting to remove that leaking valve for close to 2.5 hours after removing I took it apart
and there's a little brass sleeve that rotates with the actuator lever that was a little worn, and on the actuator arm bushing there was also a broken O ring I located a new valve and installed ..no more leaks
im gonna try to locate another O ring , rebuild it then put it to pressure and see if it holds if so I'll keep as a spare.
thanks for the info