How in the world do i service my air pack??

[Floridianson]

Take offs were not in the best shape?

 

[stancanpara]

Take offs came from one of my other deuces... swapped them out and the other truck doesn't have any problems (with the old one or the one out of my main Deuce)...

 

[stancanpara]

They are both the 'old style' but like I said, the other truck has no problems...

 

[stancanpara]

I have the bed off it right now to do a transfer case swap and now I'm thinking it might be a good idea to replace some/all of the brake lines??? They look fine with no rust problem on the outside, but they are another area to eliminate while access is easy...

 

[M35A2-AZ]

Floridianson and rlwm211, thanks guys will give that a try!!

 

[rlwm211]

check ypur brake pedal free play

This is as close a thread that I can find on my problem which is actually opposite of this problem. I pump the brakes up and sometimes they are fine, but over time the brake pressure seems to build and build until the brakes pretty much lock up... I bleed a brake and it is fine again for a while but it will inevitably build up again... I have completely flushed the system and replaced with new silicone, I have replaced the master cylinder and air pack (with take offs) and it persists... I'm clueless.... Is there some kind of check valve some where in the system? I can't seem to find any literature reflecting this in the TMs... Perhaps I'm just blind and missing it somewhere.....?

This would indicate that although the brakes work properly, the master is not releasing the residual pressure in the system. Here is a check to do.

With the truck off, and no pressure in the air system, open the door on the floor and remove the cap on the master. With your hand, press the brake pedal until it gets really firm. Release it slowly and watch for an upstream of brake fluid in the master just ahead of the main port to the piston. If your pedlal linkage does not have freeplay the piston does not retract far enough to allow the fluid to return to the resevoir and keeps the brake pressure on, even though you have your foot off the pedal. There is a tiny vent hole directly ahead of the main feed port and you should be able to see flow back into the resevoir. As I said, do this slowly as it can shoot up in the air if there is significant pressure in the lines. No sense wasting DOT5.

The TM covers the correct freeplay but to save you time, essentiall there should be 1/16 to 1/8" of movement of the plunger before it contacts the piston in the master cylinder. This allows for explansion by the aluminum in the master and keeps proper freeplay when the truck is hot.

Post your results of this test and hopefully one of the members can help...

RL

 

[BimmerPower]

I prefer to lube mine on the inlet of the air going in.

A little oil goes a LOOONNNGGGG WWWWAAAYYY so
use it sparingly.

Better to lube it a couple of times a year than to flood the air pack with too much.

I have revuilt air packs where I poured the oil out as there was too much inside.

One, maybe two squirts of a pump oil can is enough.

Hope this is helpful.

RL​

Where is this inlet line??

 

[rlwm211]

If you follow the route of each air line from the driver's side of the airpack, at the middle, you will find the following.

One goes from the aircontrol valve at nearly the middle of the airpack to the back of the airpack and connects there. This is called the J Tube. If you can find this, all the rest of the airlines connect on the same casting and area.

One will come off the front of the same air control valve in the air pack and head up towards the front of the truck, possibly tying into the vent for the master cylinder. This is the air pack exhaust.

One will come off and head towards the back, but go all the way to the glad hand air connection on the driver's rear of the truck. This is the Service brake air line. You would use this to connect to a trailer if you are towing one.

Lastly, there is an airline that runs off the side of the airpack and goes directly to the air tanks that set up in the frame behind the airpack and this is the line you want to pull off at the air pack (the tank end is almost impossible to reach with the cargo body on) and shoot some oil in there. By injecting oil here, you lubricate the entire airpack. As I mentioned previously, use a very small amount of oil. About as much as you would use to lubricate an airtool. Shoot the oil into the air line and allow the flow of air to pull the lubricant through the air pack as oppoised to shooting it directly into the airpack.

To make it somewhat easier to access the side of the airpack where these lines connect, remove the mounting bolts and skid plate on the bottom and the air pack will swing far enough away from the frame while hanging on the rear bracket to allow you to access the airlines.

Note, the airlines are roughly half inch in diameter, and the brake lines are half that size. All the hydraulic lines connect either to the passenger side, or the end of the airpack towards the front. These lines need not be touched in this process.

I hope this makes this less confusing.

There is a pretty good diagram in the mid level TMs that discuss removing and replacing the airpack and although you are not actually doing this, seeing how things connect in a drawing would most likely be of great help.

I hope this is helpful.

RL

 

[BimmerPower]

RL, thanks for the informative post. I hope to do this tomorrow and see if my brake problems are solved!

 

[BimmerPower]

I wish someone had a database of you tube videos with basic maintenance of these trucks. Makes me want to start something like this (kind of like the powerstokehelp on youtube). Makes things so much easier when you can see is first hand!

 

[Floridianson]

I still say remove tool box is easer. The TM's did say three good squrts but I don't know how big there squrt is. Don't forget you are trying to get the felt to absorb some of that oil so it lubes the wall of the air pack. A little to much will do nothing to hurt.

 

[plym49]

If you follow the route of each air line from the driver's side of the airpack, at the middle, you will find the following.

One goes from the aircontrol valve at nearly the middle of the airpack to the back of the airpack and connects there. This is called the J Tube. If you can find this, all the rest of the airlines connect on the same casting and area.

One will come off the front of the same air control valve in the air pack and head up towards the front of the truck, possibly tying into the vent for the master cylinder. This is the air pack exhaust.

One will come off and head towards the back, but go all the way to the glad hand air connection on the driver's rear of the truck. This is the Service brake air line. You would use this to connect to a trailer if you are towing one.

Lastly, there is an airline that runs off the side of the airpack and goes directly to the air tanks that set up in the frame behind the airpack and this is the line you want to pull off at the air pack (the tank end is almost impossible to reach with the cargo body on) and shoot some oil in there. By injecting oil here, you lubricate the entire airpack. As I mentioned previously, use a very small amount of oil. About as much as you would use to lubricate an airtool. Shoot the oil into the air line and allow the flow of air to pull the lubricant through the air pack as oppoised to shooting it directly into the airpack.

To make it somewhat easier to access the side of the airpack where these lines connect, remove the mounting bolts and skid plate on the bottom and the air pack will swing far enough away from the frame while hanging on the rear bracket to allow you to access the airlines.

Note, the airlines are roughly half inch in diameter, and the brake lines are half that size. All the hydraulic lines connect either to the passenger side, or the end of the airpack towards the front. These lines need not be touched in this process.

I hope this makes this less confusing.

There is a pretty good diagram in the mid level TMs that discuss removing and replacing the airpack and although you are not actually doing this, seeing how things connect in a drawing would most likely be of great help.

I hope this is helpful.

RL

I took some photos of the air pack in my Deuce for reference.

If I am not mistaken, this is an old style air pack:



To confirm the your description of the air line connections:



where:

'A' is the J tube.

'B' is the line to the glad hand at the rear.

'C' is the line to the front (vent/exhaust).

'D' is the line to the air tank that you open to introduce some air tool oil.

'E' is a switch - to what? One connector is not original, and the wire is clipped.

 

[052]

Thanks for the photos and line indentification. That helps alot.

 

[plym49]

Thanks for the photos and line indentification. That helps alot.

I was actually hoping for someone to confirm that I interpreted rlwm211's written description correctly. I *think* I have it right, but would like to check.

 

[plym49]

I still say remove tool box is easer. The TM's did say three good squrts but I don't know how big there squrt is. Don't forget you are trying to get the felt to absorb some of that oil so it lubes the wall of the air pack. A little to much will do nothing to hurt.

I plan to remove the tool box as it also gives me the chance to more easily deal with some rust inside the tool box. Does the TB come out without removing the fender or anything else?

 

[Ford Mechanic]

I took some photos of the air pack in my Deuce for reference.

If I am not mistaken, this is an old style air pack:

View attachment 278625

To confirm the your description of the air line connections:

View attachment 278624

where:

'A' is the J tube.

'B' is the line to the glad hand at the rear.

'C' is the line to the front (vent/exhaust).

'D' is the line to the air tank that you open to introduce some air tool oil.

'E' is a switch - to what? One connector is not original, and the wire is clipped.

I was going to oil my airpack today during lunch and was comparing your of the lines with mine, and where they match up to. Mine is a short style airpack and B in your pic goes to the air tanks on my truck. Ran out of time later I'll track down the rest. But has anyone else seen this?

 

[Ford Mechanic]

Bear with me apparently the enter key has stopped working with this site only?? A is J pipe .....B is routed to air tanks..... C is routed to the glad hand.....D is the vent, headed to the slobber tube...... Truck stops fine, no issues, just trying to do some PM that I'm sure hasn't been done in a long time

 

[welldigger]

My truck has the short air pak also. There is no oil port and I don't like the idea on removing the j-pipe. 2 reasons for this....#1 the threaded bushing that holds it in place is very, very tight. I don't know what they use to torque that thing but I bent my wrench attempting to remove it. Bushing didn't budge. #2 the other end only has a small o-ring to seal it with. I do my best not to disturb o-ring seals.

So to lubricate I remove the main air supply line then squirt oil in and then replace air line.