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Topic: Airing Up Tires With Onboard Compressor (Read 924 times) previous topic - next topic

Airing Up Tires With Onboard Compressor

Would someone please provide the procedure for using the onboard compressor to put air in the tires. Thanks.
Larry
Larry and Terry
Ex 2004 U270 36'

Re: Airing Up Tires With Onboard Compressor

Reply #2 –
Start engine.

When air dryer purges, indicating full PSI has been reached, air tires.

If tire pressure is close to full system pressure, as pressure drops in the tank, you can speed the process by having a second person tap the service brake until the governor reaches "cut-in" pressure and the compressor comes back online until "cut-out" pressure is reached.

Brett
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020

Re: Airing Up Tires With Onboard Compressor

Reply #3 –
Brett,
Thank You. Is it possible to air up the tires with the 12 volt auxiliary compressor?
Larry
Larry and Terry
Ex 2004 U270 36'

Re: Airing Up Tires With Onboard Compressor

Reply #4 –
I would say no. It would take forever to air tires with it and would probably not have enough pressure
previous 1984 35 ft ORED 250 HP 3208 Cat       
previous 1998 40 ft U295 CAI 325 hp Cummins
previous 2003 40 Ft u320 build #6140 450 Cummins M11.                                                         
1999 Mazda Miata
Ron, Nancy, Tipper the cat, Max The dog
1997 U 270 36 ft build number 5174 8.3 Cummins

Re: Airing Up Tires With Onboard Compressor

Reply #5 –
Another issue with the 12 VDC compressor is that they have a "much less effective" air dryer than the engine-driven compressor.  And you don't want to add water/moisture to your tires.
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020

Re: Airing Up Tires With Onboard Compressor

Reply #6 –
Never tried it, but in Mexico I watched a guy in a Country Coach with a completely flat front tire clip on the hose end to the valve stem, start the engine and let it idle. He sat down and before his XX was finished the tire was full.
1994 U280, Build 4490
Deming, NM.

Re: Airing Up Tires With Onboard Compressor

Reply #7 –
Quote from: wolfe10 –
Another issue with the 12 VDC compressor is that they have a "much less effective" air dryer than the engine-driven compressor.  And you don't want to add water/moisture to your tires.

Dry air.  Much better.  Less rusting of the cord belts inside the tire.  Used to see failed and worn MH tires and normally rust showed in the inside.  Thin rubber over the steel cords.  Moisture goes through it over long enough time at 100 psi I guess.

Clip on sure would be easier than pushing I did the other day.

Bob
"Riding and rejoicing"
Bob
1997 U320 40' Mid entry, build 5132,  wtbi ce27, 4th owner
2007 Solara convertible
2 prodeco tech outlaw ss electric bikes

1095 watts solar
08 Ls 460 and a sc430
2000 Ford F-250 superduty 4x4

Re: Airing Up Tires With Onboard Compressor

Reply #8 –
I have a small air compressor with tank that provides 135 max psi located in the basement below the coach aux. comp.  I installed this compressor to operate the Zip Dee awning after I had the control box and arms rebuilt.  They, Zip Dee, set their air control min @ 110 psi and we were having problems with the aux. comp. achieving that pressure and operating the awning.  Jimmy @ Zip Dee told me to do it and I did.  Before the new small compressor I would use the engine method to fill the tires.  My current method is pretty quick and can do it by my self.  My air quick disconnect for the main coach compressor is located next to our propane tank.  I drain the aux. aux. compressor tanks regularly to limit moisture.  I should probably install something to catch the air b4 it goes into the tires.
Scott & Carol Seibert
2001 42' double slide U320 - Sold
Previous - 2002 36' U320

Re: Airing Up Tires With Onboard Compressor

Reply #9 –
Brett Wolfe said:

"Another issue with the 12 VDC compressor is that they have a "much less effective" air dryer than the engine-driven compressor.  And you don't want to add water/moisture to your tires."

So if this compressor should not be used to air tires, does it have another purpose? If not, why not just disable it or even remove it? Just trying to get educated - thx.
Royce & Denise, MC #17410
'01 U320 4220 ISM450 Build #5895 SOLD
Toad: '10 Honda CR-V

Travel makes one modest. You see what a tiny place you occupy in the world. - Gustave Flaubert

Re: Airing Up Tires With Onboard Compressor

Reply #10 –
Royce,

12 V compressor is used to maintain level in airbags with HWH system. Not a good idea to disable it.
Don Hay
'92 Grandvilla, U-280
The Hayfever Express
Build #4055
'97 GEO Tracker
Life is like licking honey off a thorn.

Re: Airing Up Tires With Onboard Compressor

Reply #11 –
Besides keeping the HWH leveling, as Don says, it's also used to

maintain the slide bladder inflation and provide vacuum for deflating bladders for slide extend/retract

maintain the interior step cover (aka "porch")

maintain the exterior air step, if so outfitted

can be used (with "air tank" combiner switch) to start bringing main tanks up to pressure before departure (courtesy to other campers so they don't have to listen to the main engine idling as long).  I think in this mode it feeds the wet tank, but I'm not positive.

Learn every day, but especially from the experiences of others. It's cheaper!  - John C. Bogle

2000 U320 36' non-slide / WildEBeest Rescue
2003 U320

Re: Airing Up Tires With Onboard Compressor

Reply #12 –
I think I get it now. There are two compressors - the engine-driven compressor and a completely separate 12 volt compressor. If the 12 volt compressor supplies air to the air bags and all the other stuff that Michelle mentioned, what does the engine-driven one provide air pressure for?
Royce & Denise, MC #17410
'01 U320 4220 ISM450 Build #5895 SOLD
Toad: '10 Honda CR-V

Travel makes one modest. You see what a tiny place you occupy in the world. - Gustave Flaubert

Re: Airing Up Tires With Onboard Compressor

Reply #13 –
Our '91 has a 120V on board aux compressor but this requires either starting the genny or shore power to use it. I added a 12V compressor. I use the 12V quite often to air up the suspension enough to pull out of the garage so I don't fill it with diesel fumes, to top off the tires, and as mentioned, to minimize annoying other campers when pulling out at 6 am. I designed the 12V compressor with a small 2 gal tank to collect moisture before going to the coach air system. Compressor CFM
Peter and Tammy Fleming
1991 U300 GV 40 - Sold, owned for 4 years
Downsized to Roadtrek Popular 210 class B

Re: Airing Up Tires With Onboard Compressor

Reply #14 –
Bama-Fan.
How about your brakes?
No RV! Have hung up the keys.
In the past: 2016 Winnebago Era, 1994 Foretravel U240, 1995 Foretravel U240 (wide body), 1999 Foretravel 320, 36 Foot, 2003 Foretravel U320 38 foot,

Re: Airing Up Tires With Onboard Compressor

Reply #15 –
Some of use the Power Tank, I have a 15 cuft model, still on the 1st fill after a few years.  Do not use much, but it is quicker to add air than any air hose I have ever used, truck stop or my 5 hp 185 psi in our shop.  Carry it around like a set of golf clubs, lil smaller/shorter package.

Re: Airing Up Tires With Onboard Compressor

Reply #16 –
Quote from: BamaFan –
I think I get it now. There are two compressors - the engine-driven compressor and a completely separate 12 volt compressor. If the 12 volt compressor supplies air to the air bags and all the other stuff that Michelle mentioned, what does the engine-driven one provide air pressure for?
On our 1997 coach, the 12VDC compressor only supplies air to the air bags when the coach is parked in "Level" mode and the engine is off. It is only useful for relatively small adjustments. All other compressed air is supplied from the "big" compressor on the "big" engine. The air from the "big" compressor goes through an air dryer. That dry air is used to operate brakes, air suspension while moving (or parked if pressure is sufficient), step well cover, outside step, and air horns.

Later model coaches use a bigger, better 12VDC compressor to do the stuff that Michelle listed.
J D Stevens
1997 U295 CAI 36' Build #5085
2002 Subaru Outback
Motorcade 16869
Bellville, TX

Re: Airing Up Tires With Onboard Compressor

Reply #17 –
Royce:  Without the big engine compressor, your air brakes are non-existent. 
Don Hay
'92 Grandvilla, U-280
The Hayfever Express
Build #4055
'97 GEO Tracker
Life is like licking honey off a thorn.

Re: Airing Up Tires With Onboard Compressor

Reply #18 –
Quote from: Carol & Scott –
I have a small air compressor with tank that provides 135 max psi located in the basement below the coach aux. comp.  I installed this compressor to operate the Zip Dee awning after I had the control box and arms rebuilt.  They, Zip Dee, set their air control min @ 110 psi and we were having problems with the aux. comp. achieving that pressure and operating the awning.  Jimmy @ Zip Dee told me to do it and I did.  Before the new small compressor I would use the engine method to fill the tires.  My current method is pretty quick and can do it by my self.  My air quick disconnect for the main coach compressor is located next to our propane tank.  I drain the aux. aux. compressor tanks regularly to limit moisture.  I should probably install something to catch the air b4 it goes into the tires.
Scott - I'm a bit late asking about your note above due to recovery from recent knee replacement surgery.  I too have a Zip Dee Auto-Awn and was suggested by Jimmy at Zip Dee to install a separate compressor for the awning.  Since you have gone ahead and installed Jimmy's suggestion I would like to know how you went about it and where the connections were made. I too use a 135# pancake compressor to occasionally inflate my tires and thought to use it to supply air for my Auto-Awn.  Could you possibly reply with your solution and possibly add some pictures?  Thanx!
Ron Sedgley
Former 2002 U320 - Custom 38' Owner
            (2007 to 2021)    Build No. 6001