97 M1078 -- Spare Tire Boom Stuck Extended Out From Truck

[Littlejacy]

Hey all! Clearly new to this forum and group. My spare tire boom is stuck extended out from the truck at roughly 45 degrees or so, hence, I cannot drive it. My cab tilt does still work however. Whenever I try to either raise or lower completely the boom, the Air/Hydraulic unit may give one or two audible clicks, then stop. It sounds as though it is physically bound up, or air locked. I mention air locked due to the fact that I had failed to note that the reservoir was empty and finally filled it in an effort to maybe get the boom working to no avail. I am going to rebuild the A/H unit soon as it is pissing out waaay too much fluid through the vent. Yet I do not understand what is seemingly physically holding that strut from allowing the boom to move at all. I truly believe that I've isolated the issue to the spare tire operation/function of the unit itself, seeing as the cab raise function and air bag systems are cooperating with me at this juncture.
How do I rectify this?
No spare is dangling off of the boom currently, I removed it with my front loader fortunately, to alleviate stress on the system (I thought), and to be safer.
Operation of the hand pump yields no benefit to the spare tire boom....in fact, pump feels like it is binding up after two or three pumps.
Can this spare tire system be air-locked somehow?
Any input is appreciated as I am new to this LMTV machine and I LOVE IT TERRIBLY and am looking forward to gaining more knowledge!
Please help me, and point me in the right direction!

 

[Andyrv6av8r]

Check is probably stuck in the cylinder from sitting and can't be repaired. Check out this thread.

Spare Tire Cylinder

Please see attached photos of adapted cylinder to my LMTV 1078 A1. Original cylinder locked up and would not extend no matter what I did to it. Went to Tractor Supply and got a County Line Brand, 2 inch bore with 16 inch throw, Tie-rod style cylinder. Had to grind some material off the...

www.steelsoldiers.com

 

[Littlejacy]

My man! Yet another reason I am so blessed to be with this group!
In the coming 2 weeks, I'll not only be rebuilding the air/hydraulic unit but going to Tractor Supply it appears. Thing is, this damn boom was working before when I didn't have a tire on/in it. Meaning it worked for demonstration purposes I suppose. Ha, it never fails though: the minute I actually tried to lift and mount the new wheel/tire combo up there...well, here I am crying the blues to all of you!
Thank you for steering me in a great direction!!

 

[Ronmar]

Alternately try to raise and lower the crane, either with the hand pump or the AOP. Select raise, pump till solid, select lower pump till solid repeate again and again. Mine stuck once and repeated cycling freed up the safety in the cylinder and allowed it to start working. Good luck!

 

[Third From Texas]

Alternately try to raise and lower the crane, either with the hand pump or the AOP. Select raise, pump till solid, select lower pump till solid repeate again and again. Mine stuck once and repeated cycling freed up the safety in the cylinder and allowed it to start working. Good luck!

This ^^^^^^

 

[Coffey1]

That's what happens they work perfectly then all of a sudden they stop and it always seems to be the tire ram!
Mine stuck and never worked again had to replace it.

I've come to the opinion that it needs to be exercised every so often to prevent lockup moisture in fluid trusts check valve's and they stick

 

[Suprman]

I have seen them air bound and you have to crack a line and bleed a bit.