MY Airpack Rebuild with Photos!

[DeucesWild11]

Crap! Thanks for the info.. I'll get me some of that O ring lube.. if I can't find it is there anything else that will do?

 

[dozer1]

I was taught that it is best just to use whichever brake fluid you are going to use esp for seals that hold brake fluid in. Now if there is some o-rings in an area that only seals air and not brake fluid, the forementioned o-ring lube or air tool oil should do the trick.

 

[DeucesWild11]

Ok, I calmed down a little now.. that WD40 scared me for a minute.. I googled it and found this scientific study on chemicals and oils and what effect they have on O rings.. Based on the study looks like the O ring doused in WD40 was OK no sign of any change. Not saying it's the best thing but at least I feel better that it didn't show it swelling or shrinking.. Attached pic shows the findings of the study.. but here is the link.. it's pretty interesting.. What ever you do Don't use Carb Cleaner or Gasoline on O rings!

Chain O-ring WD-40 exposure effects study and results - ADVrider

 

[ARYankee]

I'm sorry if I freaked you out but that is what I was always told as well. Don't use WD40 on O rings or anything that was oil based. I was told that it wasn't good.

 

[DeucesWild11]

No problem, I just wanted to make sure the o rings weren't going to break down on me.. I am sure there will always be debate on what oil to use where..

 

[reloader64]

Thanks for the write-up. I need to rebuild mine and honestly, I've been stalling. It doesn't look all that difficult. Also, thanks for the part numbers on the cylinder hones. I'll try to get my air-pack off the truck this afternoon. I already have the rebuild kit.

Scott

 

[DeucesWild11]

Good luck Scott, it's not that bad if you take your time and be patient about it. If you are fairly mechanically inclined it should be no problem. There are no real tricky spots just your standard springs and bolts. Just be careful not to scratch up the piston rod when taking the piston off the top. There should be a screwdriver slot at the top which would help you keep it from turning as you take the nut off the top. If that doesn't work use a vise with soft jaws or put two pieces of wood in between so that you don't scratch up the piston rod.

If you run into any issues PM me with your # and I'll try to help.

The only somewhat tricky seals were these (pics) getting them off and then back on.. With the first pic it was a little hard getting the old seals off and over the larger part on both ends but they do stretch enough, just lube up the new ones a little.

 

[seabeeut]

Thanks looking at the same job coming up
still undecided about rebuilding or just buy new to get the truck on the road
then play with the old one?

 

[dezert ratt]

time for a 5ton airpack rebuild. Just checked my brake fluid, it was empty. Looked under the truck and saw brake fluid residue on the airpack vent.

 

[DeucesWild11]

An Airpack vent cool! Guess they thought about the 5 ton a little.. Mine spit at me through the slobber tube as I was right in front of it! Guess I got lucky..Ha.

 

[roady]

Excellent post and write up. Thanks for the details and I will certainly bookmark this one......

 

[DeucesWild11]

So now that the Airpack is rebuilt I wanted to drive it around today. I still had trouble getting up hills. The truck just slows down. It started to smell like brakes... crap.. turned around and went back home, only out about 3 miles round trip. Walked around the truck to check for hot hubs. The back two were warm and the front were cold... I assume I need to break down the rear hubs and rebuild the wheel cylinders.. That's my thought.. any suggestions?

 

[cattlerepairman]

So now that the Airpack is rebuilt I wanted to drive it around today. I still had trouble getting up hills. The truck just slows down. It started to smell like brakes... crap.. turned around and went back home, only out about 3 miles round trip. Walked around the truck to check for hot hubs. The back two were warm and the front were cold... I assume I need to break down the rear hubs and rebuild the wheel cylinders.. That's my thought.. any suggestions?

Before I tear everything apart, I'd first check that the brakes are indeed adjusted correctly. It is very easy to get them too tight. If the adjustment is correct and they still run too warm, then I'd start lifting those drums off....

 

[DeucesWild11]

Before I tear everything apart, I'd first check that the brakes are indeed adjusted correctly. It is very easy to get them too tight. If the adjustment is correct and they still run too warm, then I'd start lifting those drums off....

Thanks for your insight.. Hmm how do I adjust or check for adjustment without taking off the drums? If there is an easy way to adjust I'm all for it.. she does stop on a dime now..

Thanks!

 

[cattlerepairman]

Thanks for your insight.. Hmm how do I adjust or check for adjustment without taking off the drums? If there is an easy way to adjust I'm all for it.. she does stop on a dime now..

Thanks!

TM9-2320-209-20-3-2 pages 13-61 to 13-73

There is an inspection cover on each brake drum that allows you to insert a gauge. Pulling the axle shafts makes it easier, unless you can lift all four rears off the ground and place them on axle stands.

 

[DeucesWild11]

That's great I was hoping for a TM reference.. Thanks!!

 

[dezert ratt]

Just talked to eriks military surplus. $165 for a 5 ton airpack rebuild kit. That is cheaper than a $500 airpack. Now im heading to napa auto, to pick up a couple cylinder hones. Even though I have a 5 ton, this thread is still very resourcefull. :thumbup:

 

[DeucesWild11]

cattlerepairman, thanks for the tip, I adjusted the rears today.. they were definitely dragging.. ALLOT!! I did the quick adjustment on the top two bolts. Now that I know it was just an adjustment issue I will fine-tune with with the bottom bolts as in the TM.

Thanks again! I was able to get her back up on the road and enjoyed driving around town.. Only put about 100Miles on her since I got her back in Nov.. I was waiting till the brakes were 100%. I can't drive the Deuce without smiling!!

 

[dezert ratt]

just picked up 2 quarts of dot 5 at the local napa. $33 a quart! holy cow!

 

[jets1959]

Nice Job and Great pics