Portable tire inflator recommendation?

Viair used to be Made in USA, but followed the bandwagon to Asia one their reputation was established.

The MV 50 is inferior in QC and design, but is not hard at all to improve with some spit and polish.

The MV-50 is also sold as the MF-1050 and can be had on Amazon for 53$

https://www.amazon.com/Master-Flow-MF-1050-MasterFlow-Compressor/dp/B000L9AD2U/ref=sr_1_14?s=automotive&ie=UTF8&qid=1487880623&sr=1-14&keywords=viair+300p

At a minimum I would recommend retorquing the head bolts and taking a razor blade to air filter inlet holes, making sure they are wide open.

Viair is as good as there is for a 12 volt portable and has a price tag to match. The Masterflow MV-50 gets a lot of good reviews but is a cheap(er) clone of Viair. This person took one apart to see the differences in construction. Of importance when looking at these besides max. psi is CFM and duty cycle. Note that a 100% duty means a lower CFM (at least with Viair) to reduce chances of the compressor overheating.

I bought a used Viair 300P which does 2.30 cfm @ 150 psi (with 33% duty cycle), their highest CFM of all their models. I modified it by installing a Viair pressure switch inside the end cover that is on @ 90 psi and off @ 120 psi. I installed a standard female quick connect fitting instead of the normal open-ended male fitting, a pressure gauge and a male trolling plug on the cord. Bought a 25' length of super-flexible poly air hose and added a thumb pressure relief valve. Mounted the trolling receptacle on the junction box in the A-frame (a new PVC water-tite box I installed). This compressor works great and is plenty fast for even the 80 psi truck tires even when I tested by letting about 1/2 the air out.

Viair makes excellent compressors but oddly, their tire inflator gauge is cheap junk. I returned the new one I bought. Don't waste your money on one. I was unable to find a good one without spending around $200-300 and just use a standard tire chuck & digital gauge. The pistol grip gun that Viair uses (lower left photo) is the same quality as $10 ones like at Harbor Freight and elsewhere. I also did not like the cheap recoil hose that came with the Viair gun and it went back with the inflator gun.

Here's a vote for CO2 tank.. I use it all the time to inflate by airbags, truck tires and 5er pin AirRide bags to 100 psi..

I also use it at home to power air tools, etc.. best part is, it's completely silent and quick.

www.powertank.com

DougE wrote:
I really like the Craftsman Cordless Inflator. You just clip it onto the valve stem and pull the trigger. No wires to hook up. I've had any number of brands of plug-in compressors and this really simplifies the process. (The whole C3 group of tools is really a great investment!)

That's pretty slick - really like the simplicity! :B

For those using a 12 vdc tire inflator I'd suggest replacing any cigarette lighter plug with a standard 7-pin Bargman so you can just plug the inflator into your truck. I've in fact converted all my exterior 12 vdc devices to Bargman connectors, both male & female, so I can power anything from any 12 vdc power source of either sex. :B

I really like the Craftsman Cordless Inflator. You just clip it onto the valve stem and pull the trigger. No wires to hook up. I've had any number of brands of plug-in compressors and this really simplifies the process. (The whole C3 group of tools is really a great investment!)

BurbMan wrote:
This is a nice little unit that works well for topping off tires to maintain correct pressures. Priced right too, click pic for link.



If you plan to "air down" to 10 psi for off-roading, you'll need something a little more substantial like the Viair 400P that has both enough CFM and PSI to inflate all of your tires back to road pressure. This is what I use when I come off of the beach.

We have the same Harbor Freight compressor. IT'S been great.

Note that these portable on demand compressors all have passive air chucks. if not hooked to a tire they still bleed air out the tire chuck so as to not build pressure, as there is no tank to hold it.

I thoroughly despised the screw on chuck which came with my masterflow Mv-50, and replacing that was the reason I did all the modifications I did to it.

The screw on Chuck still had a quick air release which required being a precise angle with no torque applied, so it basically had to be screwed on, held in place during inflation, then unscrewed quickly, and anytime I was threading or unthreading it it was bleeding pressure.

My masterflow mv-50 now has a 1/4 NPT receptacle in head, a better coiled airhose, and a passive locking tire chuck with lever. I drilled a small hole thought the portion which depresses the valve so it cannot build pressure in the line.

Other modifications to this compressor were removing the horrid crimps inside the endcap to relay, adding strain relief on the cord, a 80MM comnputer fan to blow over the head, Adding 45 amp anderson powerpoles to the 14awg power cord, and putting grease in the big air pockets between cylinder and finned head for the better transfer of heat from the cylinder.

Also the air filter which came with it, had a bunch of plastic mold flashing on the inlet holes that severly restricted flow, easily remedied with a razor blade.

It can pull 16 to 19 amps depending on the voltage it receives. I was considering replacing the 14awg with thicker, but Time to fill is not really an issue, so higher voltage and a faster spinning motor is not really required in my use.

I've not actually measured the voltage drop at the relay in the endcap when running, but I have run it directly off of my adjustable voltage power supply whose range is 13.12 to 19.23. It sounds kind of sick at 13.12v input voltage and much faster and smoother at 15.5v.

You need a "CLIP ON" air chuck, not a "SCREW ON" chuck.
Clip on

This is a nice little unit that works well for topping off tires to maintain correct pressures. Priced right too, click pic for link.



If you plan to "air down" to 10 psi for off-roading, you'll need something a little more substantial like the Viair 400P that has both enough CFM and PSI to inflate all of your tires back to road pressure. This is what I use when I come off of the beach.

Viar 88P works for me. Viar RV400 is nice but overkill for my needs. Make sure if you get a 12V pump that it hooks direct to your battery.