air compressor for inflating tires

moparmaga2 wrote:
The on board compressor on a diesel pusher WILL NOT work for more than 100 PSI easily. Most mid to heavy weight diesel pushers call for 120-125 PSI in the front tires. Being low on air 20-25 PSI is very significant, as most times the two front tires are at their maximum weight capacity with full air PSI in the tire.


We have many discussions on this site about how a toad brake system may net you two extra feet stopping distance on these big mid to heavyweight Diesels making you "safer" :R, but for any fellow diesel pusher owners, PLEASE put that 120-125 PSI in your front tires. If your Front Tire blows out due to being underinflated or overloaded at 70 MPH, you most likely screwed and there will probably be a REAL safety issue!

But the the on board compressor will if you know how to work it! Lots of RVers and over the road truck drivers use the engine's air compressor for airing up tires and even to operate air tools. But the engine has to be operating at higher RPM to gain the necessary air pressure. And we have tire air gauges to insure proper air pressure in tires.

wa8yxm wrote:
Some generic comments on air compressors
If your RV has air brakes and thus an on board compressor.. That's all you need, just get the proper hose and fittings.

Again, as has been stated on this thread, the on-board compressor will not work for the mid to heavy weight diesel pushers. For our purposes, we will define Mid Weight as GVWR 35,000 lbs + up to 60,000 lbs heavyweight.


The on board compressor on a diesel pusher WILL NOT work for more than 100 PSI easily. Most mid to heavy weight diesel pushers call for 120-125 PSI in the front tires. Being low on air 20-25 PSI is very significant, as most times the two front tires are at their maximum weight capacity with full air PSI in the tire.


We have many discussions on this site about how a toad brake system may net you two extra feet stopping distance on these big mid to heavyweight Diesels making you "safer" :R, but for any fellow diesel pusher owners, PLEASE put that 120-125 PSI in your front tires. If your Front Tire blows out due to being underinflated or overloaded at 70 MPH, you most likely screwed and there will probably be a REAL safety issue!

If a person has a coach with air brakes like I do, where do you connect to get the air supply. Does it feed off the reservoir or does it have a place to connect off the compressor itself? I wouldn't mind having a place to connect a quick disconnect with a hose attachment to use if a tire is low or even to use for an impact wrench if needed.

Some generic comments on air compressors
If your RV has air brakes and thus an on board compressor.. That's all you need, just get the proper hose and fittings.

If you drive a Gasser as I do.. Sears has a very nice 4 gallon 150 PSI pancake job that works well and has no problem with tires over 100 PSI

12 volt compressors are not really nice when it comes to a 22.5" wheel.. Not good at all. Since the MH has 120vac I use the sears device when I need it.

To answer wny pat's question, why do you need a compressor when you already have one on board. Because the on board compressors will typically turn off at 120 and back on around 100 psi. If you need more than a 100 psi in your tires, you have to bleed air to get the compressor to cycle back to 120. It can be a long and frustrating process to Air your tires. I require 120 in the front tires so I use two solutions. One a pancake compressor good for up to 150 when I am at home, and I use an air pressure doubler when on the road . The doubler is a small diaphragm pump that does run off the coach air and it doubles the air pressure. They are made by SMC for use in industrial pneumatic control. Mine fits in the palm of my hand. The only problem is they are not cheap. I suppose they go for 250 now.

Gents,
It's always nice to have "Options" when it comes to having compressed air in our coaches for various reasons. After having (7) different Jeep Wranglers over a 25 year period, and all of them having an engine driven air compressor, it's definitely a force of habit having a good supply of air while out and about.

Yes, those of us who have diesel pusher units have a full supply of air, and the source is of course, an engine driven air compressor. And, many have outputs for use as tire filling stations etc. But, sometimes starting the big beast up, possibly in prepping for an early morning departure, just to utilize the engine driven compressor to top off a tire, might not be looked on too favorable by fellow campers.

So, out comes the "auxiliary compressor". And that can be one of many different models and makes. I'm not a fan of any 12V unit due to the very low CFM output of all of them. Yes, some claim HIGH PSI but, that high psi is momentary at best. High PSI in a volume the size of a basket ball is not overly hard to achieve from one of those. But, trying to achieve high psi on some thing the size of 255 80 22.5 or the 300 80 22.5 is pretty hard to say the least.

Many, including myself use the Sears unit as an auxiliary compressor for such a task. It seems to put out a fair SCFM at a rate that's tolerable for most. As stated, there are multiple makes and models so, just make sure the volume and SCFM is acceptable so you're not there for hours on end, just to top off one tire.
Scott

joema62 wrote:
VIAIR VIAIR-40046 400P-RV VIAIR Portable I have identified this air compressor as a potential candidate for our integra rv. Have not found specification on its air capacity and pressure ability. Is there anyone that help

Why do you want a 12 volt air compressor when your engine has it own air compressor??? If fact your engine hads a air compressor that works so well that makes the Viair perform like a toy! I mean, we are talking about a Entegra Aspire, are we not??? It has a Cummins ISL turbocharged 450 HP engine 1,250 lb. ft. torque at 1,400 RPM and every one of them that I know of has a air compressor.

I have the VIAIR 400P portable compressor. I think max output is 150 psi. I routinely use it to air up my tires to about 115 psi. I've had it for over six years now with no problems at all. If you buy one, be sure to get the inline guage/hose that has the right pressure range for your needs. I think the standard guage is a 100 psi guage. I upgraded it to a VIAIR inline guage with a higher max pressure.

Yes on on-board compressors...In fact I just put one on my Pace Arrow.... after my first 5000 mi trip and being the kind of guy that does all my own work I decided that never again will go on the road without sufficient tools to repair minor + emergencies.
I installed a 125 PSI husky 8gal, 120 V in my basement. Would not fit height wise so I removed the motor, and built a bracket to mount it on the side and removed the wheels and handle.FITS SO NICE NOW.
Now I have 50' air hose, air tools, and piece of mind. WE always run our Onan underway because of air and freezer so I always have power anywhere /anytime.
I carry the containers to even change my oil if needed. Self contained...ME... you better believe it.Dont ever want to be towed for something minor that I can fix.

rv2go wrote:
Can you not use the on board air system to inflate your tires?

I have seen where some coaches have a quick disconnect usually by your generator area where they can attach a hose with a quick disconnect and inflate their tires if needed. Sure would like to see where that line connects to on the coach so that I could install one on mine.

Well, I was referring to a diesel that has air brakes and an air compressor already. Was wondering if you connect to the air reservoir or to the compressor itself.