Lmtv CTIS PCU Solenoid PN

[DeMilitarized]

Does anyone have the part number or an eBay listing for the 3 solenoids on the pneumatic control unit under the passenger side kickplate? Not talking about the pressure transducer.

 

[coachgeo]

under kick panel is the solenoid for the engine cooling fan and the solenoid for the "in between" rear axle locker if you have the 6x6.

Can you shoot a pic of the three your referencing?

 

[DeMilitarized]

under kick panel is the solenoid for the engine cooling fan and the solenoid for the "in between" rear axle locker if you have the 6x6.

Can you shoot a pic of the three your referencing?

The 5 gold colored cylinders are the solenoids that control the air valves in the pcu(should only be 3 but this pic is from a mtvr). The transducer is the black sensor looking connection on the front middle.

 

[coachgeo]

poof

 

[coachgeo]

View attachment 890885
The 5 gold colored cylinders are the solenoids that control the air valves in the pcu(should only be 3 but this pic is from a mtvr). The transducer is the black sensor looking connection on the front middle.

ahhhhhh...... so your referring the ones "under the cover of CITS's PCU manifold" found under the kick panel...... as mentioned in below thread

Diagnosing CTIS M1078

Yes, I have downloaded the Tech Manual and thank you for sharing that. My question and I haven't found it in the site is that pertaining to Software for Computer diagnostics of the system. Is it obtainable? And where might it be located? And has any person on this site done it and know it? I...

www.steelsoldiers.com

 

[DeMilitarized]

ahhhhhh...... so your refering the ones "inside the box" under the kick panel...... as mentioned in below thread

Diagnosing CTIS M1078

Yes, I have downloaded the Tech Manual and thank you for sharing that. My question and I haven't found it in the site is that pertaining to Software for Computer diagnostics of the system. Is it obtainable? And where might it be located? And has any person on this site done it and know it? I...

www.steelsoldiers.com

Yes but looking for the part number for the solenoids. I know they are bad but can’t find them for sale anywhere.

 

[coachgeo]

Yes but looking for the part number for the solenoids. I know they are bad but can’t find them for sale anywhere.

don't recall any discussion about them specifically either. hmmmm?

 

[coachgeo]

Did more research... there is discussion in here that as I understand it none of those 3 work if there is not enough pressure in the wet tank. Common issue it seems. Folk have to turn the valve on the air compressor up a little more so the tank can get to 120lb? That pressure is when the solenoid by the tank then opens up power for the PCU to be operational system.

Don't see anything about anyone replacing them or the PCU itself even. (Pressure Control Unit's 3 solenoids)

what is making search hard is most internet things won't search by 3 letters... so when we write with military / mechanics slang-abbreviations we cut our own ability to search

 

[DeMilitarized]

Did more research... there is discussion in here that as I understand it none of those 3 work if there is not enough pressure in the wet tank. Common issue it seems. Folk have to turn the valve on the air compressor up a little more so the tank can get to 120lb? which is where they solenoid by the tank then opens up power for the PCU to be operational system.

Don't see anything about anyone repalacing them or the PCU itself even.

I swapped my parts truck solenoids in and it works now and they are open loop on volt meter. Definitely bad solenoid.

 

[Ronmar]

All of them, thats weird. @superman may have an idea, but nothing I have seen shows the solenoids as a discrete component. There are at least two manifold block variants used on the LMTV that I have seen and they use different style pilot solenoid assemblies to manipulate a small amount of air to open and close the large volume core valves inside the PCU manifold. The coils themselvs may be a fairly standard 24v solenoid coil, you would just need to find one with the right bore length and diameter to fit over the mount tube…

 

[DeMilitarized]

All of them, thats weird. @superman may have an idea, but nothing I have seen shows the solenoids as a discrete component. There are at least two manifold block variants used on the LMTV that I have seen and they use different style pilot solenoid assemblies to manipulate a small amount of air to open and close the large volume core valves inside the PCU manifold. The coils themselvs may be a fairly standard 24v solenoid coil, you would just need to find one with the right bore length and diameter to fit over the mount tube…

I have seen people replace the coils but idk what they are.

 

[Instinct]

I know this is an older thread, but there is in fact a parts breakdown of the PCU to include the solenoids in the M915-17 family TMs. It's pretty much the same CTIS as the FMTVs.

 

[GeneralDisorder]

I know this is an older thread, but there is in fact a parts breakdown of the PCU to include the solenoids in the M915-17 family TMs. It's pretty much the same CTIS as the FMTVs.

That is correct. The military had component level breakdowns for the later 900 series but decided to service the PCU as a complete assembly on the FMTV as it was too involved to have troops rebuilding them.

Same situation with the air compressor, third members, transmissions, and lots of other things. If it's a major assembly that has to be removed for service they have civilian contractors rebuild them at Depot (-30) level.

 

[aw113sgte]

I

I have seen people replace the coils but idk what they are.

I think there was a parts break down in the MTVR manuals, they likely have the same solenoid.

 

[aw113sgte]

I

I think there was a parts break down in the MTVR manuals, they likely have the same solenoid.

Nevermind....it shows the 5 solenoids as a "harness".
Shouldn't be too hard to figure out, you have the ID, OD, height, voltage, I bet digikey will have some options.

 

[Ronmar]

Nevermind....it shows the 5 solenoids as a "harness".
Shouldn't be too hard to figure out, you have the ID, OD, height, voltage, I bet digikey will have some options.

For the coil and wattage.

i have seen 2 different solenoid valve types used on our PCU modules. I am not sure wether they use the same coil assemblies... The solenoids portion consists of small pilot valves used to manipulate air to cycle the larger bore valve core/spool valves…

 

[aw113sgte]

Can you post up the OD, ID, height, coil resistance? Can probably cross reference something.

 

[SkybreakerOverland]

Wondering if anyone ever got the part numbers for the solenoids. I have a dead control solenoid in my PCU on an m1088

 

[Ronmar]

have you confirmed it is indeed a bad solenoid coil? the PCU connector on mine is jammed up against the structure, and if yours is also, you could be experiencing a wiring issues for the control solenoid circuit at the PCU or somewhere else in the dash, and not necessarily a bad coil.

beyond that it should be a fairly generic 24VDC relay/solenoid/actuator coil. i would look for a part on the coils themselves and order from that...

From what I have seen there are at least 2 different 3 valve PCU styles(I have overhauled two types so far), and their difference is that they use slightly different type/style solenoid valves. The solenoid valves are modular(coil, tube core and needle valve) and can be disassembled. The coils look similar but I am not sure if they are interchangeable(i suspect they probably are). Their needle valve controls pilot airflow to move the larger sliding valve spools in the main valve body. A problem with the control spool not sliding properly in its bore might also present as a bad solenoid.

This would not be my first case of chasing bad dash wiring between CTIS controller and PCU, and certainly not my first experience with a fouled PCU spool valve

 

[SkybreakerOverland]

have you confirmed it is indeed a bad solenoid coil? the PCU connector on mine is jammed up against the structure, and if yours is also, you could be experiencing a wiring issues for the control solenoid circuit at the PCU or somewhere else in the dash, and not necessarily a bad coil.

beyond that it should be a fairly generic 24VDC relay/solenoid/actuator coil. i would look for a part on the coils themselves and order from that...

From what I have seen there are at least 2 different 3 valve PCU styles(I have overhauled two types so far), and their difference is that they use slightly different type/style solenoid valves. The solenoid valves are modular(coil, tube core and needle valve) and can be disassembled. The coils look similar but I am not sure if they are interchangeable(i suspect they probably are). Their needle valve controls pilot airflow to move the larger sliding valve spools in the main valve body. A problem with the control spool not sliding properly in its bore might also present as a bad solenoid.

This would not be my first case of chasing bad dash wiring between CTIS controller and PCU, and certainly not my first experience with a fouled PCU spool valve

I did confirm. Pulled the PCU out and applied ground and 24v power to the pins.

A - ground
F & E - 24v, 2 solenoids clicked

B - ground
D - 24v, no click.

Diagnosis, dead control solenoid