Air Tank Conversion Kit
Article by Mark Trotta
Quite often, a portable air tank is more convenient than rolling out the air compressor hose from the garage and then rolling it back up. And it inflates tires a lot faster than those cheap 12-volt air compressors.
This portable air tank is nothing more than an old empty Freon tank fitted with an Air Tank Conversion Kit. I put it together 30 years ago and it's been ready for use ever since!
If a friend has a low or flat tire on the road, you can fill up the air tank, drive out to them, and add air to the deflated tire. Now the car can be safely driven back home or into town for repair.
From time to time, I need a few pounds of air in one my car's tires. Although I have a garage air compressor, it's often easier to bring the air tank to the tire. Instead of hooking up a 20 foot hose to another 20 foot hose to reach the car in the driveway, I simply fill up my air tank at the workbench, then carry it where needed. This is especially handy when your project car or truck is in the middle of a field!
Milton Air Tank Conversion Kit
The Milton S682 tank conversion kit is designed to convert old R12 Freon tanks to portable air tanks. It's easy to install and works very well. Wrap the threaded parts with Teflon tape while assembling for an air-tight seal.
Milton S-682 Product Specifications
- PSI Range: 0-160 PSI
- Filler Valve: 1/8" MNPT
- 1-1/2" Dial Gauge: 1/8" MNPT Back Mount;
- Single Head Air Chuck: 1/4" FNPT
- Air Hose: 1/4" MNPT
The Air Tank Conversion Kit includes a filler valve, round gauge, manifold assembly, air chuck, and four feet of air hose.
The Milton S682 kit is U.S. made, which is probably why mine has lasted so long.
Shop: Milton Tank Conversion Kit
Another good reason to convert an old Freon tank into an air tank is that you're saving metal from sitting in a landfill forever. Re-purposing metal is a worthwhile cause. Every little bit helps.
Does Not Fit All Air Tanks!
According to Amazon user feedback, the number one complaint against the Milton S682 kit is mis-application. It was designed to convert empty R-12 Freon tanks into portable air tanks, which it does very well. These are the old-style refillable jugs that have the black T-handle, and they're getting hard to find. They are not designed to work on newer, non-refillable Freon tanks (134a and 410a) that have one-way valves to prevent re-use.
Not For Propane Tank Conversion!
These kits are not for propane tank conversion, although I have seen people on the internet adapting them to work (not recommended).
The kit may work with an empty helium balloon tank, as they do have a threaded top.
As you can tell from it's outward appearance, I've had my converted air tank for quite a while now. Since it is over 30 years old, I no longer fill it up over 100 psi, and have never filled it up past 125 psi. Even at that level (the gauge goes up to 160 psi), a blow-out would not be catastrophic, but I'm sure the noise would scare the heck out of you!