29 replies to this topic

[Medeiros]

An RV friend suggested that I purchase a portable air compressor that would allow me to get my motorhome from a remote location to where I could get a leaking tire repaired or replaced.

 

A local tire dealer told me that any compressor I purchased that supplied less than 250 psi would be inadequate and would not adequately fill the tires on my 40 ft. motorhome. Everything I see for sale, on the internet, rates out at 150 psi and will, supposedly, fill my tires to 30 psi in five minutes. As you all know, the tires on our motorhomes require 95 psi. If I were to purchase one of these compressors, would a longer running period get my tires inflated enough to get me down the road?

 

I am considering the purchase of a VIAIR 400PA-RC Automatic Air Compressor Kit. Any information and suggestions will be be greatly appreciated.

 

Clyde   

 

 

[desertdeals69]

On your 40 foot motorhome you have an air system which runs through a dryer and is about 135 lbs which works for tires.  I have been using my that way for 14 years.  Has plenty of air for a 3/4 inch air wrench and will fill tires just fine.

[Tireman9]

Not sure what your tire dealer is talking about. Almost all large shop air compressors top out at 150 to 175psi. Anything higher would be considered "Industrial".

Here are a couple of links to companies that supply air compressors to body shops and garages. If you look at the specs you will see 175 psi is the max with many at 150 or lower.  TIP   Northern.

 

Now back to your question. I think the reality is that you occasionally find that you need to top off your tires with just a few psi to reach your goal cold inflation. If you have a TPMS and a little experience you will know when you need to add 5 psi or so. You should be able to get air at high enough pressure at truck fuel stop if you have a Class A needing 95 to 120 psi cold.

 

Here is a post from my blog on how to get your tires topped off for free. 

[wigginsjsr]

My DP with air brakes has a connector for an air hose.  I use this to keep my tires up to pressure on the MH and the Dingy.  I have 110 psi in the front tires, and the connection supplies more than adequate pressure.  Are you sure you don't have a connector?

[kingfr]

Porter-Cable makes a 4 Gallon pancake compressor that tops out at 165 psi. About $185 at Amazon, free delivery if you are a Prime member. Weighs about 25 lbs and fits nicely in one of my underbelly compartments.

[desertdeals69]

If you have on board air why would you want to carry and additional piece of equiptment?

[kingfr]

There are several reasons.

 

The onboard air pump does not cycle until the pressure in the tank gets below about 90 lbs, therefore to get to 100 -110, you must stop filling and bleed the tank multiple times to approach 100 lbs. The compresser on my coach shuts off at 125 lbs, so this is a pita. The Porter Cable that I mentioned above cycles at 135 lbs, and shuts off at 165 lbs.

 

The recommended pressures for tires are cold pressures, if you crank and drive, you now have warm tires, or hot tires, depending upon how far away the closest truck stop is.

 

I prefer not to crank and idle my diesel if I am not going to drive somewhere, so I don't want to crank, fill and bleed, and then shut back down. Also, I like having the ability to use pneumatic brad nailers for small projects around the "house" without cranking the diesel. I don't work hammers very well. Of course, this means even more equipment in the MH!

[desertdeals69]

I check my tpms and I know what the pressure is after driving all day.  Mine in the winter after a 300 mile drive raise about 8 lbs so if I have a tire that is say 3 lbs lower I can add 3 lbs from the motorhome air system and of course it is up to full pressure.  I then check it in the morning when its cold to verify I have the correct pressure.

[kingfr]

That works, I don't have a TPMS on my coach.

[desertdeals69]

I use Tire Minder both on the coach and the toad.  Wouldn't  travel without the system.  You never know if a problem is in the making.

[jc21014]

We carry this compressor from Sears in our rig along with an extension cord.  Fire up the gennie and air away with no problems on our 22.5 tires. 

http://www.sears.com...15309000P?mv=rr

[desertdeals69]

We carry this compressor from Sears in our rig along with an extension cord.  Fire up the gennie and air away with no problems on our 22.5 tires. 

 

http://www.sears.com...15309000P?mv=rr

We carry this compressor from Sears in our rig along with an extension cord.  Fire up the gennie and air away with no problems on our 22.5 tires. 

http://www.sears.com...15309000P?mv=rr

Why don't you just plug it in with the inverter on?

[jc21014]

Why don't you just plug it in with the inverter on?

That is a possibility, just never thought about doing it that way.

[desertdeals69]

Another way of doing it would be to start your engine and when the air is built up then air your tires as necessary then leave on your journey.  You need to air it up before you drive anyway.

There are several reasons.

 

The onboard air pump does not cycle until the pressure in the tank gets below about 90 lbs, therefore to get to 100 -110, you must stop filling and bleed the tank multiple times to approach 100 lbs. The compresser on my coach shuts off at 125 lbs, so this is a pita. The Porter Cable that I mentioned above cycles at 135 lbs, and shuts off at 165 lbs.

 

The recommended pressures for tires are cold pressures, if you crank and drive, you now have warm tires, or hot tires, depending upon how far away the closest truck stop is.

 

I prefer not to crank and idle my diesel if I am not going to drive somewhere, so I don't want to crank, fill and bleed, and then shut back down. Also, I like having the ability to use pneumatic brad nailers for small projects around the "house" without cranking the diesel. I don't work hammers very well. Of course, this means even more equipment in the MH!

[kingfr]

Another way of doing it would be to start your engine and when the air is built up then air your tires as necessary then leave on your journey.  You need to air it up before you drive anyway.

You don't understand my post. The engine is running. The pressure in the tank is 125PSI, the tire pressure is 100PSI. The tank pressure drops as the tires are filled. The Pressure in the tank equalizes withe the tire at 102PSI, but the compressor does not kick in until the tank pressure is 90PSI, therefore I must bleed the tank pressure down to 90PSI before the compressor will kick back in to raise the pressure back to a number high enough to force more air into the tire to get to 110PSI. Sure I can do that, but it makes airing up a PITA. The separate compressor is easier and more straightforward, in my opinion , If you like doing it your way, bless your heart and go for it, I like my way better and that's what makes the world go around!

[Tireman9]

You might watch this Video

[kingfr]

That video re-enforces my point above, except that I didn't mention taking air out of the tire!

 

I like having a separate compressor that has the capability to handle big tires, and it can power nail guns, inflate bike tires, floats and balls, etc.

[desertdeals69]

That video re-enforces my point above, except that I didn't mention taking air out of the tire!

 

I like having a separate compressor that has the capability to handle big tires, and it can power nail guns, inflate bike tires, floats and balls, etc.

Now I understand where you coming from.  When I have to add air, its only 1-3 pounds and thats roughly every 4-6 months.  I have plenty of reserve air in the tank for that.  If you tire is down 10 lbs you must have a leak if its overnight or if it is a longer period of time thats too much to be losing.

[BillO]

I understand where the OP is coming from.  My old coach has an air system that tops out at 110 psi -- exactly what I need for my tires.  Trying to bring a tire up to 110 psi with a source of the same pressure is a real pain. 

 

I found an inexpensive compressor at Home Depot that goes to 135 psi.  It's their house brand -- "Husky" -- and probably made in China.  However, at the time it was only $100 and serves the purpose for intermittent use.  Like most small compressors it does not have an air drier on it, but NAPA had some inexpensive in-line driers designed for painters that can handle the pressure.  That gives me a decent dry air source for topping the tires at CGs with little effort.

 

This particular model is a bit bulky so it takes up more bay space than I'd like and it does require that I bleed some air from the small tank to trigger the compressor start before filling the tires because the low pressure trigger is a little too low.  Even with those drawbacks the price/benefit work for me.

[kingfr]

Now I understand where you coming from.  When I have to add air, its only 1-3 pounds and thats roughly every 4-6 months.  I have plenty of reserve air in the tank for that.  If you tire is down 10 lbs you must have a leak if its overnight or if it is a longer period of time thats too much to be losing.

Actually, when they were down below 100 lbs, it was because I hadn't added air in almost a year. I kept putting it off because of laziness, not wanting to add air in a truckstop because of warm/hot tires and the fact that using the engine compressor is a pita.