Need help with 923A2 air issue - Low output

[Valleyordnance]

Hi Guys,

Did a search here and didn't find much to help me.

My 923A2 was running perfect, Took it to Tuscan for a pickup at DM and the air pressure dropped below 60, Put it in park and rev'd the engine and it would not build air, it didn't drop but wouldn't go up, hung right at about 60 PSI. Took the truck out on a back road and once I got up to 40 MPH it would make air up to about 85 PSI. I managed to limp back to PHX with the truck, but was nervous as ****!

I replaced the governor, after doing some research here on SS. Did not help.

Any suggestions/comments?

Thanks for the help in advance

Chris R

 

[Suprman]

Check and see if the expello valve bottom of air dryer is leaking if so insert finger push up. Your compressor unloader valve could be sticking also sometimes you can take it apart and clean it.

 

[fuzzytoaster]

Check for any air leaks with the truck off and airing up the system with an air compressor. Check the air dryer to see if the bottom flap is sealing correctly. Generally a poke or prod with a skinny instrument will reseat it. Those are the easy/common steps.

 

[Coffey1]

Also check compressor head gasket for leak.
Andy's truck did same thing then it really let go.
Sitting could build air then driving it came up some then gasket let go

 

[Valleyordnance]

No noticeable air leaks if I pressurize the truck with a glad hand. Without diving into the TM's is the unloader valve a PITA? I assume it's part of the compressor top end correct?

Another Military truck guy I know told me to put a bunch of air tool oil into the Emergency side and pressurize the truck - said that should lube and stuck valves. Is this good advice? Don't want to cause more damage!

Thanks for the responses guys!

Chris

 

[dawico]

I am guessing an unloader issue. It is on top of the compressor. There are a few threads about it.

Take the inlet line off (coming from the governor) and put a few drops of transmission fluid in there to lube it.

 

[Coffey1]

No the unloader is some what simple.
Air gun oil should not hurt anything I've put it in mine.
And that gasket you won't know about without spraying it with something or it totally lets go.

 

[dawico]

Soapy water does wonders for finding leaks.

 

[OilfieldRoughneck]

Mine did this for two days, then I drove on a washboard gravel road and everything is back to normal. Dunno