Rebuilding a air assist unit

[m16ty]

Anybody ever torn into a Ait-O-Matic unit? Not the cylinder but the drag link.

I was all ready to do a hyd PS setup but while looking in a truck junk yard today I run upon a old bus that has a Air-O-Matic unit on it (this is the first time I've ever seen one of these on a civilian vehicle). I talked to the owner and he said he was just going to scrap the bus so I could have to Air-O-Matic for free.

I'm all set up to put it on the deuce but it looks kind of rough. I was wanting to tear it down to make sure it wasn't frozen up inside but I don't want to get into something I can't get back together.

 

[welldigger]

The torque valve isn't "supposed" to be rebuilt. However several members have done it. I believe m-35tom claimed to have rebuilt one. Might want to give him a shout.

Even if you try yourself and fail it was free. Whats it gonna hurt?

 

[m16ty]

Yea, there's a sticker on it that says "do not disassemble, return to factory for repairs" but I figure that if somebody built it, it could be repaired.

I know it was free but I don't want to tear it up if I can help it.

 

[ivbeenrokd]

Go for it, and take pictures!

 

[doghead]

Try a search for Maradyne.

I once spoke with someone from the factory and they said it is not rebuild-able. They use a machine, not a human(iirc).

I don't recall anyone on the site successfully reassembling one either. (I'd be glad to be corrected on that)

 

[Hainebd]

I would not disassemble. Install and if bad. Buy a new. I put these on heavy trucks decades ago. We disassembled an old one and there is just discs inside to move air. I believe it works on equal force to ram and the valve releases to turn. Been a while. Clean, replace o rings and install

 

[welldigger]

Try a search for Maradyne.

I once spoke with someone from the factory and they said it is not rebuild-able. They use a machine, not a human(iirc).

I don't recall anyone on the site successfully reassembling one either. (I'd be glad to be corrected on that)

Turbotim did. I thought I read another thread where m-35tom claimed to have done it but I can't remember.
http://www.steelsoldiers.com/showth...ing&highlight=having+trouble+with+my+steering

 

[m16ty]

I installed the torque valve today and ran it on shop air just to see if it would work. I'm getting good air out of the port in tension (left turn) but I'm not getting much air in compression (right turn). I think I'm going to go ahead and put it all together, add lots of air tool oil, and hope it's just a little sticky from sitting so long.

If I decide to tear into it I'll post in the link Welldigger provided to keep all the info in one place.

 

[m16ty]

Well I got the whole setup installed on the truck today. Everything works great. It's not as good as true PS but you can't beat it for a freebie.

Because the unit came off a old bus, I had to fab up a cylinder anchor point and change the drag link ends. I just cut up another drag link I had and fabed the ends onto the unit and used some 1/2" plate to make the cylinder anchor.

Now I've got a extra PS pump I don't need since I went with the air unit but I may hang onto it and put hyd PS on another of my trucks (I just need to find a free HF54 ).

 

[welldigger]

Glad to hear its working for you. One of these days I'll install my air o matic. One of these days when it isn't so cold.

 

[gimpyrobb]

 

[ivbeenrokd]

Sounds great. X2 on the pics.

 

[m16ty]

Didn't have the camera today but I'll take some and post up.

 

[m16ty]

Here's some pics.

I know, I've got a flat that I need to fix.

 

[ivbeenrokd]

I like that you've got the cylinder up higher out of the way. Why did you decide to mount it backwards?

 

[gimpyrobb]

He had to make the air cyl mounting plate as the air system came from an OTR truck, not a deuce.

 

[ivbeenrokd]

He had to make the air cyl mounting plate as the air system came from an OTR truck, not a deuce.

Right, but is there a logical reason to put it backwards or just a preference?

 

[gimpyrobb]

Six of one, half dozen of another.

 

[peashooter]

Right, but is there a logical reason to put it backwards or just a preference?

Left turns will be easier (more assist) with the setup like this, where as right turns would have more assist with it mounted the "normal" way. Probably not too terribly noticable, but about a 100 lbs more force with the cylinder "pushing", rather than "pulling"

 

[gimpyrobb]

How does pushing VS pulling give something more force? Doesn't the torque valve supply the same air pressure to the left and right air ports?