Funky Tire Pressure Guage

[Peregrine]

Just received my super duper super slick Smitty Build Heavy Duty air compressor kit. We be styling now.

This included an air gage. When I tested it against my current dial air gage it was reading 10lbs lower. A couples of pounds is normal between gages.

While I am not going to lose any sleep over this, going to build a 4-tire@once hose setup, I am curious if anyone else has encountered this?

Thanks

 

[Brewbud]

I have had tire pressure gauges that were off by as much as 5 psi but never 10. The gauges that are mounted to the air compressors usually only read correctly when the pump is off and let to set a few seconds. My vehicles all run different tire pressures front and rear so I built a 2 tire inflator system that works very well. I may change it up to have the same length hoses on each side.

 

[bgenlvtex]

Air gauges, particularly spring bar air guages are notoriously inaccurate, 10 pound variation in 2 or 3 guages would not be surprising at all.

 

[Alanymarce]

Hmm - gauges are either made to a standard (it depends on the country what it is - here it's ICONTEC NTC 2263, which specifies a maximum error of 5%) or to whatever the gauge manufacturer thinks will be sufficiently accurate for customers to accept.

Now, a lot of gauges are sold cheaply which fall into the second category and are not as accurate as the specification requires (i.e., they do not meet the standard).

If you get a good gauge from a certified manufacturer it'll be accurate within 1 psig. The ones you find at gas/petrol stations are supposed to be calibrated routinely (they are, obviously, measuring something with safety implications), lots of them are pretty accurate, some of them are not properly maintained and less so.

We carry a good gauge as well as the one on our compressor, and routinely check tyre pressures with it when we inflate/deflate, whether at a gas/petrol station or with our compressor. The frequency with which we've found a significant difference at gas/petrol stations is probably one in 50, and our compressor has so far been consistent with the "confirmation gauge".

If I had a gauge which was accurate to only +/- 10 psi I'd destroy it.

 

[Red_Leaf_Overland]

I had an issue with the smittybilt gauge and it wasn't even consistent in its range. I swapped it out for an ARB gauge and still carry a pen style analog gauge in my kit to double check. Unfortunately smittybilt uses some oddball proprietary air fitting so I had to cut it off and attach a regular m style fitting. I did build a 4 tire inflation system to go with an air tank for my TJ but I don't have any pictures of it at the moment, but it's basically 1/4" air plastic air line with brass fittings and a manifold off the tank. Nothing pretty and sometimes I use it with my CO2 tank in the TJ and it works fine. Naughty pretty much everything from McMaster Carr.

 

[MidOH]

Pop the plug out of the gauge to vent it, and see if it helps.

Good gauges ain't cheap:

Motion Pro Professional Tire Pressure Gauge 2 1/2" 0-60 Psi - Motion Pro

Motion Pro - High quality cables, tools and controls for motorcycles, ATVs, snowmobiles and personal watercraft.

www.motionpro.com

 

[Boostpowered]

Do it enough and you'll learn to eyeball it instead of needing a gauge. You can also use a ruler and go by how many inches of sidewall there is.

 

[ptgarcia]

I've been using a good quality, brass construction, made is USA Milton S-920 pencil gauge to verify my Accu-Gage and Intercomp dial gauges and recommend them. They're less than $10 and very good.

 

[LostInThought]

Not as compact as a pencil gauge, but I've had really good luck with this one. It's accurate to 1 PSI, but EXTREMELY consistent**, and about half the price of similar gauges.

Longacre 52-52003 Tire Pressure Gauge, 2-1/2 Inch, 0-60 PSI

** If I check a tire's pressure several times in succession, I'll get the *same* reading to as near as I can read the gauge. My intuition is that it is better that all 4 tires are consistently off the pressure I intended by the same amount, than it would be for them to be at different pressures. Any disagreement?