Have a class A Winnebago and I was just wondering what others have for a portable air compressor for your tires. I have found that the small 12 volt ones really struggle to get 84 PSI in a tire or take forever. Does anyone have a good solution for bringing your tires back up to the correct pressure?
You just hit the nail on the head with that one! ALL 12V compressors struggle to achieve higher pressures in larger tires, PERIOD! Some are only marginally better at it than others. I've had a bunch of small compressors over the years including the junk Viairs. I cooked one of those "higher end" versions while trying to achieve 95 psi in one of our coach tires.
About 99.999% of them will advertise "150 psi" etc. Well, yeah, you might be able to get 150 psi if you're filling something the size of a TENNIS BALL! Compressing air is a TOUGH job. Especially for small 12V or even small 120VAC ones. The larger the VOLUME, the longer it's going to take to reach a higher desired pressure. In the old days, there were some bicycle tires that needed 120 psi. You can reach 120 in something like those in fairly short order due to the small volume.
But, increase that volume to something the size of a motorhome tire and you're going to strain ANY compressor, especially a 12V model. And, in many, many cases, you're not only increasing the size of the volume but you're also increasing the pressure for them to carry much heavier coaches. So, those smaller compressors, be them 12VDC or 120VAC units, start out with 2 strikes against them in the first place.
For diesel owners, yes, you can use the engine driven compressors. But, depending how high you need to go or, how low the tire(s) is or are, even those will struggle some. But, just like smaller 12V or 120V units, they may start out filling a tire at what's called "cut out" pressure, they very soon drop in pressure because they're filling quite a bit of volume AND trying to reach a high pressure.
So, with all this garb being said, you simply seek out what you may think will work for you. I presently have an "All Top" brand dual piston 12V, 12.3 cfm compressor from Amazon that does a pretty fair job, at least on my Jeep tires. I've yet to test it on topping off our motorhome tires which are 95 psi in the rears and 90 in the fronts. We'll see how that goes sometime.
It has been suggested that many RV'ers carry and use a 120VAC "pancake" compressor. Well, maybe so, this RV'er doesn't. I carry the 12V one mentioned in our Jeep. For the coach, I carry a Harbor Freight "Fortress" model 120VAC. While certainly not the smallest 120VAC, it's without a doubt, the QUIETEST one made! It will top off our coaches tires and at a somewhat decent fill rate. But, you need 120VAC to run it so, take that into consideration and use what you need to supply it.
Amazing deals on this 2Gal Ultra Quiet Jobsite Air Compressor at Harbor Freight. Quality tools & low prices.
www.harborfreight.com
There are lots of 12V ones to choose from. There's also many 120VAC units to choose from. And lately, there's the cordless ones that are migrating into the market. I know very little about those. Your choice.
Scott
