M809-series (M818) Air Brake Retrofit

Steel Soldiers is supported by:

MyothersanM1

19K M1 Armor Crewman
Steel Soldiers Supporter
1,863
61
48
Location
Culver City, CA
With the axle caps on, king pins greased and brake dust/cover plates installed, the front tires went back on this morning. I properly torqued the lug nuts and axle cap nuts.
A word about the cover plates...bolt them onto the spider before you install them on the knuckle. The bottom most mounting bolt is impossible to install as the bottom of the knuckle does not lend to much clearance to work in there. The top plate went on fine and the bottom is held on with one bolt. The bottom plate feels secure but rattles a bit.

DSC_0006.jpgDSC_0008.jpgDSC_0007.jpg
 

MyothersanM1

19K M1 Armor Crewman
Steel Soldiers Supporter
1,863
61
48
Location
Culver City, CA
Yesterday, I finished the plumbing to the air dryer.

As I posted before, I used 1/2" braided steel teflon hosed, two 10AN 90º swivel fittings and two 10AN to 1/2" NPT adapters for the discharge line. I used a 1/2" NPT hex coupling attached to the nipple already on the air compressor to attach 10AN adapter and
90º . The line is clamped to the frame just below the air compressor, runs through the old master cylinder bracket, past the transfer case then just past the hand brake where it terminates at the air dryer. I clamped it to the inner frame behind and to the rear of the left fuel tank. The line attaches in the reverse at the air dryer with the same 10AN fittings.
DSC_0144.jpgDSC_0145.jpgDSC_0136.jpgDSC_0137.jpgDSC_0139.jpg

The supply tank line is 5/8" nylon reinforced tubing using 5/8" air brake X 1/2" NPT fitting at both ends. The line runs from the delivery port, up through the frame, to the inside of the spare tire rack then attaches to the supply tank which is located behind the cab (older photo, but the tank is still in the same mounted position).
DSC_0141.jpgSDC12234.jpg

The 1/4" nylon control line runs from the air governor, then joins the air tubing "bundle" following the same path as the discharge line. The control tubing is clamped to the same crossmember as the air dryer. The line connects with 1/4" push-to-connect X 1/8" NPT at the governor and
1/4" push-to-connect X 1/4" NPT at the air dryer.
DSC_0142.jpg

I started up the truck and let the air build. At compressor cut out, the air dryer let off a healthy blow down. All is good. I have not connected the electrical line for the heat element. I just need to run a wire form the run/start switch back to the dryer, but the weather is nice here and there is no real urgency to finish that part fast.

The last plumbing to be connected is the two delivery lines from the frame to the front air chambers. I ordered some spring guard for these lines. I will install the lines once they spring guard arrives.

Lastly, I greased the s-cam tubes and slack adjusters.


 
Last edited:

MyothersanM1

19K M1 Armor Crewman
Steel Soldiers Supporter
1,863
61
48
Location
Culver City, CA
I plan to finish up tomorrow and call the job "complete" making the truck full mission capable. I will install the hoses from the frame to the front air chambers. But, there will be some small additions beyond that. I do have on order some hose spring guard to add a little more protection in those vulnerable areas. I will install the spring guards once I get them.
Hose Spring Guard.jpg

I have obtained two NOS 3 gal. air tanks and two Velvac bracket kits (#501051) which will serve as additional storage for the primary and secondary air tanks. The tanks measure 7" X 19". I also have some of the cable pull type drain valves for each tank.
DSC_0001.jpgDSC_0002.jpg
 

MyothersanM1

19K M1 Armor Crewman
Steel Soldiers Supporter
1,863
61
48
Location
Culver City, CA
Well, I'm going to call this project complete. Last Saturday I installed the front brake chamber hoses, but without the full spring guard. I took it on drive down to a nearby self service car wash. These brakes on this truck are a dream compared to the old air-hydraulic. I have to get used to the lower hanging pedal as compared to original which sat higher.

Later in the week, around Tuesday/Wednesday, I put on the spring guard for the front brake hoses. I also installed the additional air tanks, plumbed them into their respective tanks and added a cable drain valve to each one. The forward tank is for the primary and the rear for secondary.

DSC_0148.jpgDSC_0147.jpgDSC_0151.jpgDSC_0150.jpgDSC_0149.jpg

In the near future I am going to add a tractor protection valve and trailer supply valve in addition to replumbing the trolley valve to service the rear gladhands. I want the tow lines to be up to spec. For now the major work is done and I can now enjoy my truck once again.
 

silverstate55

Big Dummy
Steel Soldiers Supporter
1,815
67
48
Location
Cedar City, UT
WOW, first-class work and glad to hear that it performs beyond your expectations! Great job, thanks so much for excellent photos & write-up!!
 

MyothersanM1

19K M1 Armor Crewman
Steel Soldiers Supporter
1,863
61
48
Location
Culver City, CA
I found the correct dust shields that fit the particular spiders I used. I was going to annotate the p/n to the list I posted a while back, but it won't edit anymore.
So here it is...

Dust Shields, Pair
Meritor A13236Q2123

I have also obtained a PP7 trailer supply valve and a TP3 tractor protection valve. When I find some time, I'll get the towing connections up to spec and get those dust shields installed.
 

Tow4

Well-known member
Steel Soldiers Supporter
1,846
62
48
Location
Orlando, FL
I found the correct dust shields that fit the particular spiders I used. I was going to annotate the p/n to the list I posted a while back, but it won't edit anymore.
Once you finish with all the details and finalize the part numbers, post a new complete part list with any other info you need to put at the beginning of the thread and ask a mod to update your original part list post or put this info in the first post. That way the important info is in one place and it's easy to find it.

Thanks for posting this project, it's an upgrade I will be doing to my M929.
 

MyothersanM1

19K M1 Armor Crewman
Steel Soldiers Supporter
1,863
61
48
Location
Culver City, CA
On Monday this week, I was able to install all four sets of dust shields. The top shields are simple to put on as there is not much obstructing access. The bottoms are a little more difficult but manageable due to the torque rod seats and their mounting bolts. I used grade 5 3/8" x 3/4" bolts and lock washers using a liberal coating of anti-seize on each one. There are 24 bolts in all.
The shields definitely give the axle ends a more finished appearance.
DSC_0001.jpgDSC_0004.jpgDSC_0006.jpgDSC_0010.jpg
DSC_0002.jpgDSC_0009.jpgDSC_0005.jpg
 

MyothersanM1

19K M1 Armor Crewman
Steel Soldiers Supporter
1,863
61
48
Location
Culver City, CA
Well, I'm back for a little thread revival. I finally installed the PP7 trailer supply valve (Haldex equivalent), TP3 tractor protection valve and reincorporated the hand trailer brake control valve. The install included two double check valves (AKA shuttle valves) and all the associated tubing and fittings. I also added an air pressure switch to activate the stop lamps via the hand brake valve. I was not going to install this set up from the onset, but decided it will be safer in the event I am pulling a trailer and have an air line mishap.
DSC_0031.jpgDSC_0203.jpgDSC_0205.jpgDSC_0206.jpg

I first installed the supply valve which inter-connects, to both supply and control ports, with the parking brake valve on the dashboard and mounts just to the right of it. The delivery line then routes through the firewall utilizing a bulkhead fitting back to the "tractor emergency" port on the tractor protection valve.
DSC_0009.jpgDSC_0011.jpg

The hand brake valve was already in place so I just re-plumbed it all. The supply was pulled from the secondary circuit supply port on the treadle valve. The delivery was routed through the firewall with a bulkhead fitting, similar to the trailer supply valve plumbing, then routed back to the first double check (yellow) valve. This first double check valve, mounted to the crossmember to the right of the spring brake valve just behind the transfer case, routes the delivery of service pressure from either the hand brake valve (right hand fitting) or the secondary treadle valve circuit (left fitting). The center fitting and tubing is for delivery to the second double check valve attached to the tractor protection valve "tractor service" port.
DSC_0013.jpgDSC_0016.jpgDSC_0018.jpgDSC_0017.jpg



 

MyothersanM1

19K M1 Armor Crewman
Steel Soldiers Supporter
1,863
61
48
Location
Culver City, CA
This is a close up of the push-to-connect air brake fitting tee which delivers secondary service pressure to the spring brake valve control port and then on to the first double check valve.
DSC_0019.jpg

The tractor protection valve and second double check valve are mounted up in the left frame next to the air dryer. With a street tee fitting, the second double check valve and air pressure stop lamp switch were connected to the "tractor service" port. The second double check valve routes the delivery of service pressure from either the first double check valve (hand brake valve or the secondary treadle valve circuit) on the foreground fitting or the primary circuit from the treadle valve on the background fitting. The existing rear gladhand connections to the tractor protection valve are connected as follows: left/rear to "trailer service" port and right/rear to the "trailer emergency" port.
DSC_0015.jpgDSC_0014.jpg

All the tubing was dressed up and secured with clamps and zip-ties where needed. The last thing to do is complete the secondary stop lamp switch wiring and connect to the air dryer heater lead.
 
Last edited:

MyothersanM1

19K M1 Armor Crewman
Steel Soldiers Supporter
1,863
61
48
Location
Culver City, CA
I installed a new M915 style battery box http://www.steelsoldiers.com/showthread.php?148460-M915-Battery-Box-on-M809-series. In doing so, the two inboard right-side air tanks I installed to supplant the primary and secondary tanks had to be removed for proper fitment of the box. That's OK, I just bought a couple of the larger M939-series driver's side tanks to replace the smaller ones.

One was mounted to the outboard frame between the battery box and the cab. The tank brackets bolt to the frame through the battery box saddles. It supplants the primary circuit. The plumbing only needed to be shortened up by clipping the tubing.

M915 Battery Box-Right Fuel Tank Install (18).jpgM915 Battery Box-Right Fuel Tank Install (17).jpgDSC_0064.jpgDSC_0068.jpg


The other was mounted inboard with one bracket on the backside of the front fuel tank saddle and the other bracket bolted to the backside of the battery box. This tank is part of the secondary circuit. As far as the plumbing on this one, I ran a new length of tubing and added a loom clamp on the back of the battery box.
IMG_0095.jpgIMG_0094.jpg
 
Last edited:

MyothersanM1

19K M1 Armor Crewman
Steel Soldiers Supporter
1,863
61
48
Location
Culver City, CA
I have decided to simplify the spring brake control system. I get to eliminate three valves when all is said and done. I was going to use this arrangement early on, but the parts (SR-7 valve) were more expensive at the time. So, I found and purchased an SR-7 Spring Brake Modulating Valve with a one way check valve for a decent price which replaces the R-14 Relay and SR-1 Spring Brake Valve.
IMG_0316.jpg

View attachment sr7_spring_brk_modulating_valve.pdf

I also obtained a Haldex (p/n 3064940) equivalent to the MV-3 Dash Control Module which combines the function of both the PP-1 Parking Control Valve and the PP-7 Trailer Control Valve into a neat package. It also replaces a double check valve which is mounted between the primary and secondary air tanks. This valve will add a new run of 3/8" tubing from its tractor port to the park control port on the SR-7 valve. However, it does also eliminate some other runs of tubing once the SR-1 valve is removed.
IMG_0317.jpgIMG_0318.jpg

View attachment mv3_dash_control_module.pdf

On the SR-7 valve the balance port is located on the side of the valve that would be mounted closest to the frame crossmember. In order to mount it with a fitting installed, I would have to provide some stand-off from the crossmember for clearance. The mounting studs are also closer together the on the R-14 relay. I made up a flat bracket from 1/4" scrap that would extend the valve out away from the crossmember and also make up for the closer stud spacing.
IMG_0323.jpgIMG_0324.jpgIMG_0325.jpg

In order to mount the Dash valve, I fabricated a mounting plate from 2" x 3/16" steel plate. The finished length is 8". The valve must hang from beneath the dashboard as the is no room to incorporate it anywhere else. It will be located just below where the existing valves are located to the left and below the steering wheel.
IMG_0314.jpgIMG_0321.jpgIMG_0322.jpg
 
Last edited:

MyothersanM1

19K M1 Armor Crewman
Steel Soldiers Supporter
1,863
61
48
Location
Culver City, CA
I preassemble all fittings to the SR-7 valve and installed a length of tubing on the balance port which will connect up to the existing balance fitting on the R-12 relay. The first thing I did on the truck was pull a new length of 3/8" tubing that would connect the push-pull spring brake valve in the cab to the SR-7 valve. The tubing runs from the driver's side air tanks, along the frame and back to where the relay and modulator valve are located on the crossmember.

I removed the R-14 valve allowing the the R-12 to hang free. No connections on the R-12 change.
Here is the before shot...
SDC12614.jpg

I bolted uo the SR-7 valve using the fabbed mounting plate using to the lower bolt holes on the crossmember bracket. This mounting position will give clearance for the spring brake hoses. The R-12 can be bolted back in on its own to the top holes. The red 1/2" tubing is from the secondary reservoir to the valve supply port. The balance loop connects the same as with the R-14 valve; no change there. The control port on the SR-7 connects to the secondary service line that also feeds the front axle brakes. The park control port which is the top most port is connected directly to the dash control valve with the new tubing line I discussed in the last post. The hoses to the spring brakes connect back the same way to the SR-7 as they did on the R-14.
Here are the finished after shots...
IMG_0332.jpgIMG_0347.jpg

Moving forward, I removed the SR-1 spring brake valve. The line from the reservoir was removed and that port on the reservoir will feed the primary tank I installed on the right side of the truck.
Here's a before shot...
DSC_0018.jpg

The yellow double check valve controls air flow to the trailer from either the secondary (front axle) circuit or the handbrake. All the tubing connections I needed were all there once removed them from the SR-1. Using a push-to-connect tee fitting, I ran a jumper tube to the check valve from the secondary circuit tubing. From what I teed is tubing that runs back to the new SR-7 control port. The last pic shows the emptiness left behind after the SR-1 removal.
IMG_0335.jpgIMG_0334.jpgIMG_0333.jpg

 
Last edited:

MyothersanM1

19K M1 Armor Crewman
Steel Soldiers Supporter
1,863
61
48
Location
Culver City, CA
All tubing and fittings connected to the front ports of both the primary and secondary driver's side tanks were removed. This also included the double check valve as the new dash control module has an integral double check that performs the same function.
Here are the before VVV pics...
DSC_0005.jpgDSC_0007.jpg

The new plumbing is much simpler and neater. The 1/2" red tubing is the secondary (spring brake) supply for the SR-7 valve, the black 5/8" tubing is the primary (service brake) supply to the R-14 relay valve and the 3/8" tubing is for the tractor spring brake control leading from the dash module to the SR-7 park control port. The 3/8" tubing passes through the floor board by way of a bulkhead fitting previously installed with the original plumbing.
IMG_0326.jpgIMG_0327.jpg

I pulled primary and secondary supply air from the ports on the treadle valve to feed the the new dash module. The tractor supply line can be seen underneath all the other lines. It leads down to the bulkhead fitting I mentioned earlier in the floor board. The trailer supply line which I installed previously (see post #70) did not change.
IMG_0340.jpgIMG_0341.jpg

The PP-1 and PP-7 were removed. The fabbed bracket plate for the new dash module mostly covers up the 7/8" holes where the original two valves were installed. Prior to connecting up all the air lines, I marked and drilled out three mounting holes for the the bracket plate. The module bolts up the bracket using 1/4"-20 x 1" through the cast in threaded mounting ears. The bracket bolted to the dash with three 5/16"-24 x 1" bolts and nuts. Space is tight underneath the dash so I mounted the bracket to the dash first, then connected the primary, secondary and trailer lines to their respective fittings, then bolted the module to the bracket. Once the module was in place, I connected the tractor supply line from underneath the module through a 90º fitting. An important note: the AUX port on the module must be plugged or air will escape there. The dash module looks to hang low. I was a little concerned about this early on. However, it does not interfere in any way with my left leg.
IMG_0344.jpgIMG_0345.jpg
 

pevrs114

Member
163
1
18
Location
Crewe, VA
Excellent work. Very clean. What's the rough cost of the parts so far?

do you think you'll add a complete parts list at the top later on?
 

MyothersanM1

19K M1 Armor Crewman
Steel Soldiers Supporter
1,863
61
48
Location
Culver City, CA
Thanks for your compliments. I'm going to put the cost around $6K. It was the brake kit plus shipping that drove up the cost. However, it took the guess work out of finding the right parts. I'm hoping my monetary sacrifice and the posting of part numbers will help others keep their costs down if they choose to do this mod. All the parts can be bought off the shelf with the exception of some of the front wedge brake parts. I have given up thinking I will ever recoup these costs of upgrading my truck. Although, I have peace of that the brake system is much more reliable, easier to maintain and, above all, safer.

There is a partial parts list near the beginning of the thread. I have also tried to post part numbers as I have gone along. The problem is early posts are locked out to editing after three months. I tried to get a mod to help me, but they never responded back to me. I wish the posts didn't lock out especially to the thread OP.
 
Last edited:

Trango

Member
723
0
16
Location
Boulder, CO
Very nice work.

By the way, I was able to make S-cam brakes work on the front of the 5 ton by slightly clocking the spindle bolt pattern on the spiders, along with some other light mods. It took me a solid week of work to fit everything up (and countless times of deadlifting the hub/drum combo onto the spindle for test fitting!), but it now stops like a dream.
 

MyothersanM1

19K M1 Armor Crewman
Steel Soldiers Supporter
1,863
61
48
Location
Culver City, CA
Very nice work.

By the way, I was able to make S-cam brakes work on the front of the 5 ton by slightly clocking the spindle bolt pattern on the spiders, along with some other light mods. It took me a solid week of work to fit everything up (and countless times of deadlifting the hub/drum combo onto the spindle for test fitting!), but it now stops like a dream.

Do you have any pics or a thread showing your modifications?
 

silverstate55

Big Dummy
Steel Soldiers Supporter
1,815
67
48
Location
Cedar City, UT
Very nice work.

By the way, I was able to make S-cam brakes work on the front of the 5 ton by slightly clocking the spindle bolt pattern on the spiders, along with some other light mods. It took me a solid week of work to fit everything up (and countless times of deadlifting the hub/drum combo onto the spindle for test fitting!), but it now stops like a dream.
VERY GLAD to see you are still on here!

I'd also like to see pics if you have them....
 
Top
AdBlock Detected

We get it, advertisements are annoying!

Sure, ad-blocking software does a great job at blocking ads, but it also blocks useful features of our website like our supporting vendors. Their ads help keep Steel Soldiers going. Please consider disabling your ad blockers for the site. Thanks!

I've Disabled AdBlock
No Thanks