Small DC compressor to stay aired up?

[Jim Blackwood]

The Range Rover compressor is a good unit and can put out a bit over 150psi if it needs to but it doesn't put out anywhere near enough volume for a bus. For a pair of 4" or 4-1/2" airbags, yeah it'll do great if you keep the pressure under 100psi and OK but really kinda slow at 150.

The kinda volume you're talking about though you'd have to have a 100% duty cycle and it's just not built for that.

Keep in mind, you could have a fitting or seal go and dump all your air. Then you're pumping up from zero and it'll take awhile. Best to get the biggest compressor you can, that you can fit into the available space and then run it on AC. Compressors take a lot of juice, that's why the BTUs of A/C units are limited. If you need to run the generator to air up you might as well start the bus engine to do it.

Your choice whether to go with a small compressor rated for constant duty or a bigger one with a lower duty cycle. The newer 3400rpm ones are pretty compact for the air volume, generally louder but don't have to run as long. A converted A/C compressor is quiet but may need an oil trap/separator to return oil to the canister. Very compact though and possibly free. Usually a little oil in the air is not a bad thing, but you might need to add a dipstick. The bigger the better though.

The key to a quiet compressor though is in the intake. That's where all the noise is created. If you can baffle and deaden that without restricting inflow then you can pretty well silence any compressor.

Jim

[hcvdg]

Good input. I liked the Viair compressor as a ?turn key? solution. I also liked the suggestion of using a 12V fridge compressor (quiet).

The coach I?m considering has a 135 psi Porter-Cable compressor already installed (I don?t know the operating pressure of the tank).

One thought is to use a Viair compressor, or a 12V fridge compressor, to feed the bus air tank. Another thought would be to take advantage of the high pressure capability of a fridge compressor to store air at higher pressure in another tank.

If either the Viair or the fridge compressor were not up to the task of keeping the bus aired up, I would look to reduce the leaks.

Attached is a photo of a Range Rover air tank specs showing 250 psi, and 3 gal. in case anyone is looking for a tank (eBay, or a junk yard).

[bigred]

Thomas makes the little 12v DC compressor that CC used on their coaches .We were talking about this issue on here a while back and someone had one of these for sale for a hundred bucks.Good deal when you consider a new one is three hundred plus .Maybe he will come forward if he still has it. They are called "wobble shaft"compressor.Rated at 100 pounds but best I have ever got out of mine is 85psi

[dtcerrato]

We run an ancient Craftsman that won't quit. 1 hp 110vac 6.9 cfm @ 90 psi. Alum. oiled piston compressor. It safely took us from Atlanta GA to Indianapolis IN as auxilliary air when our engine compressor drive failed. Airs up the bus in 5 min. & sits next to the tool box for the air tools. Used it for a lifetime for gun nailing when we retired we took the wheels off & stuck it in the bottom compartment, tank & all. We love it.

[oltrunt]

Can't argue with an ancient Craftsman--good goods.  As far as present day pumps go I'd pay the extra for a Tomas continuous duty pump.  They are bullet proof.  I've run through a couple of the Viair continuous duty pumps which got so hot they melted their plastic lines before they quit.  Jack

[Jim Blackwood]

If you want a compressor that will last, you can't do much better than the old cast iron Champion 2 stage but you will need at least 5hp to run it. Used to be able to buy those from gov't surplus. It'll give you 150psi all day every day for decades to come and run any hand tool you have. Still made and sold too last time I looked.

Jim

[Bob & Tracey]

I have a 150psi Viair 12v compressor rated 100% duty cycle, 100psi pressure cut off switch. It takes about 45min to air up our 4104 from 0psi, is has no problem keeping up with our small leaks. We are fulltimers and have aired up the bus several times a week for almost 5 years with no problem.

Compressor is similar to this one;

https://www.ebay.com/itm/Viair-400C-Silver-Heavyweight-Air-Compressor-for-Trains-Horns-Air-Suspension/222076365904?epid=1629432093&hash=item33b4c86c50%3Ag%3AOp4AAOSwLqFV8z-a&_sacat=0&_nkw=viair+12v+air+suspension+compressor&_from=R40&rt=nc&LH_TitleDesc=0%7C0

Bob

[scanzel]

I found Viair junk, I had a 24v heavy duty that ran an additional 5 gal air tank to keep my air lock door operating, unit failed just after warranty ran out took apart and piston ring whore out not compressing air. Viair wanted me to ship and pay $45 to check plus parts and shipping back. It is sitting on shelf went with a Craftsman oil ac compressor. Oil less gets to hot causing piston ring failures.