Which Air Hose for OBA

[Token]

I recently hard mounted my dual piston QuickAir in the back of the truck.. I chopped off the fittings and lines that came on it off in favor of putting a 10ft lead hose on that routed around a few things and extend out the back of the truck.. I hadn't thougth much about it, but got bulk airline from Home Depot.. First time I ran it to air up tires it ran about 10 minutes before blowing the line off the bard fitting on the compressor.. I put it back on, tightened things down and kept an eye on it.. Before long the hose had heated up and was bubbled up near the fitting to about 2 inches. The line was rated for about 200psi, but just wasn't up to the heat the compressor makes..

Never found any airline that said it could deal with high temps.. I soon stumbled across some 1/4" hydralic hose with NPT fittings.. Not as long as I wanted, but it'll hold up to 3000psi.. It's a VERY tight fit on the 1/4 barb, so the inside of the line had to be reamed a bit to get it on, but once on, even without a clamp there is NO WAY the air compressor is going to blow the line off..

Be warned though.. The Hydralic line is steel braided (internally) and transfers a LOT of heat.. At 4ft the fittings get hot enough to leave 1st degree burns if you grab ahold of it without a towel or glove..

 

[Robert Bills]

For the OBA system on my Jeep (Thomas 12v 1/3hp compressor), I used Goodyear air hose from Harbor Freight ($14) with factory fittings on each end. I cut the hose to length and added barbed fittings at the cut ends.

Inexpensive, has worked flawlessly for 10 years without heat issues or connection leaks, and the hoses are still supple.

However, if you use an A/C compressor as an air source, you will need something more heat resistant than standard air line, at least for the first several feet of your pressurized line.

 

[poriggity]

If you use any sort of air compressor (IE a York or Sanden engine driven unit), it's always a good idea to run a check valve, and a coalescing (oil seperating) filter. Just something else to think about.
Scott

 

[DirtRoads]

Well here's a somewhat related unrelated question. After you get your air lines from the tank and route them to their destination, say rear bumper, under the hood, front bumper, or even inside the gas filler door what how are you securing that connector?

Is there such a thing as a two piece connector that could be slid through a drilled hole and then tightened together? I have been looking at setting up an OBA system this winter but this is the part where I am pretty stumped.

-Drew

 

[Patman]

You can get bulkhead fittings for pushlock and compression.

Very nice setup, slip through a drilled hole, nut tightens around the outer body, pushlock on inside, male pipe on outside for quick disconnect fitting.

 

[sasfrontier]

Check out these guys. www.poweraire.comI bought all of my polyethylene line and push lock fittings for my oba from them and haven't had any problems in 2 years.

 

[Mike_rupp]

I while ago, my brother setup his OBA system. I recommended that he use nylon 11 tubing from McMaster. I tried to find it on there, but they must not sell it anymore. Nylon 66 is used for various under the hood applications because of its high heat properties and chemical resistance. Some automotive companies are using it for intake manifolds.

The nylon 11 material might be a slightly better material for the OBA tubing application because nylon 11 is slightly more flexible than 66 so it might help in routing the tube, but nylon 66 would still be a fine choice.