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Question - assistance converting air park/emergency valves to single unit

Overdrive

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Converting Park/Trailer Manifold Valves to Single Haldex Unit

UPDATE: Mission Complete. Successful Park/Trailer manifold valve replacement. All the follow-on posts are mostly me and others trying to figure everything out. I have summarized the switch over in this first post so you don't have to troll the entire thread.

airline8.jpg

Swapped the stock 2 valve Parking/Emergency & Trailer Brake valves for the single combined Haldex valve.

Stock valves
manifold valves1.jpg manifold valves diagram3.jpg

I also replace all the air lines (3/8" OD DOT approved) to/from the new valve and added push on, quick disconnect fittings (DOT approved) on both the truck and valve. I used a PVC pipe cutter to cut the air lines. It cuts clean and does not deform the air line.

I had to rotate both the Park and Trailer knobs 90 degrees by knocking out the little pin with a punch. The valve comes setup for a horizontal orientation.

I found all the new fittings on Amazon but can also be found elsewhere. I purchased the new air line off of eBay.

Pics of new air lines and fittings under the instrument panel. I spent some time cleaning as much as possible and added a little sound deadener after I pulled the original lines.
airline6.jpg airline7.jpg airlines9.jpg

Original air lines

airline5.jpg

Fittings list (I replaced the truck side fittings as well).

FMTVs and variants may be different.
7 each 1/4" NPT to 3/8" OD Tube push on DOT approved fittings (5 on the Park/Trailer valve and two on the cab floor for Park & Trailer connections)
2 each 90 degree 3/8" NPT to 3/8" OD Tube push on DOT approved fittings (one for the supply fitting under the dash and one for the Exhaust fitting behind the heater) - NOTE: The stock Exhaust port fitting on my truck was just a 3/8" NPT to 1/4" compression fitting, not 90 degree but I noticed that the air line loops VERY close to the windshield wiper arm so I am switching to a 90 degree fitting there. I have seen pics of other LMTVs with a 90 on there so it must just be random or if repaired whatever was lying around.
1 each 3/8" OD Tube T fitting (to split the supply line from the truck for Res1 and Res2 ports on the new valve)
1 each 100' roll of 3/8" OD DOT nylon air line (green) (to replace all the air lines going to and from the Park/Trailer valve. this project doesn't need anywhere near 100' of hose I just bought it in bulk for future. Actual line used was about 20')
1 each 1/4" NPT pipe plug to cap the Aux supply port on the new valve

Port Identification From Truck to New Valve

Truck
EXHAUST - Release air from either valve (park/trailer)
TRACTOR DELIVERY - supplies air to the parking brake
TRAILER DELIVERY - supplies air to the trailer brakes
SOURCE - source of air from the truck (I added a T-fitting on this line to supply the Res1 and Res2 ports on the new valve)

Valve
EXHAUST - as it implies as you release the parking brake it dumps air out the fitting just behind the grill
TRACTOR DELIVERY - This is for the parking brake air
TRAILER DELIVERY - Supplies air for trailer brakes
RESERVOIR 1 - source of air from truck
RESERVOIR 2 - source of air from truck #2 - you must use both Res1 and Res2 to supply air to the new valve (thank you jtron79)
AUX SUPPLY - Capped


FYI: The Exhaust port behind the heater, in front of the radiator (you can see the fitting hole up behind the center of the grill in front of the heater's fresh air flap) vents two things ... The Park/Trailer valve when released and the brake pedal valve. This port is simply a fitting open to the environment not a one way valve.

I purchased green colored air line for this install just for fun and to quickly identify any air lines I replaced from stock. There are LOTS of different colors you can get if desired. Side benefit is that you can use a sharpie to id the lines easily on a light colored air line.

Use DOT certified air fittings to connect truck air lines to the valve. I headed down the path of finding a 3/8" OD compression fitting to 1/4" NPT fitting from Home Depot... ***DO NOT DO THIS***

Truck air systems are designed to "fail safe" so in the event a line comes loose, I doubt it, or you loose air pressure for some reason the park/emergency brakes automatically apply. They require air to release (if not caged).

Thank you to everyone who contributed to this successful conversion.

OD
 

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Overdrive

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LMTV Dash Manifold Valve Conversion (Park/Trailer)- (In Progress)

Converting from dual A0 truck Park/Trailer valves to the integrated single valve.

Which Ports Go Where?

1. Port identification on the stock two Park/Trailer brake valves.
manifold valves diagram3.jpg

2. Port identification on the new integrated valve (6 total)

s-l1600.jpg mvegq2XYF-jdesuXfx3RM5A.jpg
Ports
EXHAUST - as it implies as you release the parking brake it dumps air out the fitting just behind the grillTRAILER DELIVERY - This for the trailer brake air
TRACTOR DELIVERY - This is for the parking brake air
RESERVOIR 1 - source of air from truck
RESERVOIR 2 - source of air from truck #2 - you must use both Res1 and Res2 to supply air to the new valve
AUX SUPPLY - Capped

new valve port layout.jpg

How do you connect the truck air lines to the new valve?
The new valve is all female threads so how do you go from the female fittings on the plastic air lines from the truck to the new valve. The threads on the new valve are 1/4" NPT. The lines from the truck are 3/8" Compression fittings Haldex has a warning on how to tighten fittings to this valve since it is composite (seems like plastic) and states to NOT use Teflon tape.

Use DOT certified air fittings to connect truck air lines to the valve. I headed down the path of finding a 3/8" OD compression fitting to 1/4" NPT fitting from Home Depot... ***DO NOT DO THIS***

airlines4dontdo.jpg
EXAMPLE: Pic of stock compression fitting on the left and a Home Depot fitting on the right. DON'T DO THIS!!! I rigged up this line in the pic just to show my research in what fitting to use. There was no plan to actually use the hose in the picture it is just to describe different fittings. Fittings can be found at local heavy truck stores, NAPA, or online (I ordered my fittings from Granger (thank you to those that filled me in on the details).

Fitting I chose (on order) from Grainger: 3/8" OD push on fitting to 1/4" NPT fitting.
https://www.grainger.com/product/PAR...nnector-11K656

I also found some on Amazon for cheaper

http://www.amazon.com/Weatherhead-1...rue&ref_=ox_sc_act_title_1&smid=ATVPDKIKX0DER

Other stuff

1. Truck air lines. There are only 4 air lines on the truck going to/from the valves.

EXHAUST - Release air from either valve (park/trailer)
TRACTOR DELIVERY - supplies air for the parking brake
TRAILER DELIVERY - supplies air for trailer brakes
RESERVOIR X - source of air from the truck


Thanks!

OD
 

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Oxyacetylene

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I'm interested in this. I bought one of the one piece valves a while back while they were cheap. I was waiting until my dash valve(s) started leaking before making the swap. As for the benefit, for me the benefits would be that 1. the one piece valve is rebuildable, 2. The one piece valve will hopefully be easy to mount and will sit right in the dash as my valves are currently askew due to the lines pulling them sideways, 3. the one piece valve was cheaper than buying just one of the separate valves.
 

scottmandu

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I'm interested in this. I bought one of the one piece valves a while back while they were cheap. I was waiting until my dash valve(s) started leaking before making the swap. As for the benefit, for me the benefits would be that 1. the one piece valve is rebuildable, 2. The one piece valve will hopefully be easy to mount and will sit right in the dash as my valves are currently askew due to the lines pulling them sideways, 3. the one piece valve was cheaper than buying just one of the separate valves.
I've found the trailer and park valves with aluminium bodies are about $28 each new.
 

Overdrive

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I don't have a choice. Based on the setup I am going with (secret project right now) there is not enough room to mount the two separate valves. But simplification of assembly/setup with a lot less valves seems like a win. I also agree if it aint broke don't fix it but I have to move to the newer valve so here we are.

OD
 

Overdrive

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Updated original post with diagram and pics of the stock valves and air line routing. I think I have this handled. Waiting for new valve to show up.

I paid $16 for the new valve type.
 
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jjb

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That cont. port looks like the interconnect port. I think that is what restricts the trailer supply valve from working if the park brake is not released. I would assume that is internal to the single valve and not required.

interconnect 2.jpginterconnect.jpg
 

Overdrive

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That cont. port looks like the interconnect port. I think that is what restricts the trailer supply valve from working if the park brake is not released. I would assume that is internal to the single valve and not required.
Thanks jjb I will add that to my primary post. That would make sense based on how the two valves are connected.
 

73m819

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I would NOT do the single valve no matter the space limitations BECAUSE with ANYTHING going wrong with the single valve, the truck is dead, with the two valve setup, the truck can keep going if one valve dies with creative plumbing.
 

jtron79

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to connect the air lines to valve. use DOT connectors. threaded on one end and push the tubing into the other. they are cheaper locally if you have a hose supplier or big rig parts store. hose barbs are not approved and your safety is at stake.

https://www.grainger.com/product/PARKER-Male-Connector-11K651?s_pp=false&picUrl=//static.grainger.com/rp/s/is/image/Grainger/11K651_AS01?$smthumb$

I almost picked up one of these but the single i needed to replace was cheaper.

Great job on the pics.

Jason
 

Oxyacetylene

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I've found the trailer and park valves with aluminium bodies are about $28 each new.
Right, but I got one of the combo units for $25 shipped :), and they are rebuildable. My trailer valve was leaking a little, but it stopped, so I haven't bothered worrying with it yet.
 

Oxyacetylene

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I would NOT do the single valve no matter the space limitations BECAUSE with ANYTHING going wrong with the single valve, the truck is dead, with the two valve setup, the truck can keep going if one valve dies with creative plumbing.
The single combo valve is really like two separate valves in one big valve body. I think the only shared air connection between the two parts of the valve is the one interconnect that ties the trailer and park valves that jjb mentions. You could still do some creative plumbing except for that one part maybe? Also with the new style, you can take the pull knobs off, remove the top plate, and service the valve. The A1 trucks use a one piece setup like this.
 

Overdrive

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to connect the air lines to valve. use DOT connectors. threaded on one end and push the tubing into the other. they are cheaper locally if you have a hose supplier or big rig parts store. hose barbs are not approved and your safety is at stake.

https://www.grainger.com/product/PARKER-Male-Connector-11K651?s_pp=false&picUrl=//static.grainger.com/rp/s/is/image/Grainger/11K651_AS01?$smthumb$

I almost picked up one of these but the single i needed to replace was cheaper.

Great job on the pics.

Jason
I can't find a "DOT connectors" anywhere online. When I search on "truck air line fittings" I get a lot of hits and all the connectors and adapters are brass NPT fittings. The stock lines off the truck are plastic/nylon and have the little compression ring and female cap still on them to connect to a 3/8" male NPT fitting. Seems like all I need is a male to male fitting from the valve to the air line.

I see the Grainger fitting you posted it looks like it is for a bare nylon air line that you just push in like a PEX plumbing fitting. That would be the cleanest install I think but I am planning on just going with male/male fittings.
 

Suprman

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I have seen the push in fittings used on commercial vehicles before. I said the same thing "how can that be reliable" but it is they are used all over.
 

Overdrive

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ok I get it. The "DOT Fittings" are related to the push on style, as I said in my previous post, similar to the PEX stuff in plumbing. Assuming the DOT is required for safety when dealing with the nylon air hoses and the little compression fittings. But anything else seems to be strait brass NPT type connections you can buy just about anywhere.

I am not going to use those compression fittings. Just going to get brass 1/4" male NPT to 3/8" male NPT fittings to connect the truck lines to the valve. The truck air lines still have the fittings and female cap compression plugs on them so just reusing that.

So the push and compression type fittings, they are different, have a DOT approval standard number of they have been OK'd to use on truck air brake stuff... ok.

Hmmm, well I might try this push on type then. I didn't want to mess with the truck lines but this would be a pretty clean install with just push type fittings into the valve.

https://www.grainger.com/product/PARKER-Male-Connector-11K656

Thanks
OD
 
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jtron79

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Ok i see. Reducer bushings from 3/8 to 1/4 would work. The fittings on there are the same as i linked. You push or pull on the collar and the line pulls out to change them. I would be concerned about adding more leak points by using the reducers but they would be safe.

Dot just certifies them for type and pressure. They sell the same fitting non dot. Same for the hose. If its for air brakes better to err on the safe side.
 
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