CTIS deflates single tire when M923A2 shut off

[Alexsha]

So today I replaced 2 of the 3 solenoids in my CTIS and magically the system came to life. After letting it run for a while then shutting the truck off, the front axle quick release was blowing air and airing down the driver side tire. It ended up at about 20 psi or so, at which point the quick release stopped blowing air. I've been going through the Dana/Spicer troubleshooting guide and the -23 TMs to make a checklist of what to look into, but Im hoping someone else has encountered this and would share their findings.

I've tightened the CTIS fittings and there seem to be no major leaks. I need to get out the soap and water to do a more thorough check though.

Things to check:
Quick release fittings and seals
Dirt/gunk in quick release that might have left it open
CTIS wheel filter
CTIS wheel valve fittings and seals

tl;dr: what is the most likely culprit of a single wheel deflating out via the CTIS?

 

[MtnSnow]

All I can think of is the CTIS valve at the wheel has something amiss with the seat & seal (they are very prone to rust when the air drier has not been maintained)

Take a look at this thread as it shows what I mentioned
http://www.steelsoldiers.com/showthread.php?124896-The-things-I-learned-while-rebuilding-my-CTIS

 

[Suprman]

If air is blowing out quick release valves with the truck off chances are you have a bad wheel valve. Easy fix. They corrode inside and the flapper won't seal right. Sometimes you can take it apart and clean it up. Take off the hose going to the hub. No air should be coming out. You can take a plastic bag and rubber band scrunch the bag over the valve and rubber band it. If air is leaking out the bag will expand.

 

[Alexsha]

Cool. I'll get it broken down asap and see what's in there.

 

[Alexsha]

Well I took the wheel valve apart. It was nasty in there. I cleaned out the gunk and put it all back together. No change. I did notice that it basically deflates whenever the CTIS is not inflating. So the ctis is cycli g on and off a lot. When I shut the truck down I was able to remove the little cap screw on the valve and use a thin rod to push the valve shut. Would it be worth it to get a rebuild kit (new diaphragm, bolts, etc.) or am I looking at a whole new valve?

 

[Suprman]

I would find a new valve. There are 2 types they are not interchangeable due to mounting hardware.

 

[Alexsha]

Is this a front axle / rear axle difference? All mine seem the same. Its getting dark though and I didn't check model #s.

 

[Suprman]

Placement does not matter they are different. You can look and tell the 2 styles apart. One is older. Most A2 trucks have the older style I have seen a few with the newer style. The new style is the same as the ones on the LMTV trucks.

 

[Alexsha]

I think I'll try a $17 rebuild kit before buying a $100 valve. Must be made of gold.

 

[Suprman]

100 bucks they are getting expensive.

 

[Those Military Guys]

hey alexsha check you pm's

 

[charlesrg]

I wish this thread was closed with a confirmation that the valve replacement resolved or not. Having the same problem here.

 

[Suprman]

Take the line off the hub going to the valve scrunch a bag over it and rubber band down over the hose. If the bag expands then air is leaking back thru the valve.