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Topic: Adding air through the auxiliary outlet (Read 670 times) previous topic - next topic

Adding air through the auxiliary outlet

Hi all
I think I read that you can add air to your air bags through the auxiliary air line by the  fuel and propane tanks to alleviate the requirement to start the engine. Not knowing the system that well I do have questions
1 does this system have a one way valve that only allows air out on all our coaches or is there a protection valve that will not allow air input?
2  my air tanks for the brakes leak down to 40-50lbs after a couple of days resulting in my step coming down (it requires about 70lbs to keep it up) By inputting air through the auxiliary line does that add air to the brake tanks as well?
Peter    Alberta Canada
'98 U320 40'  Build 5359 M11 450 HP, Aqua hot, Blu Ox

Re: Adding air through the auxiliary outlet

Reply #1 –
Look for a post by Roger to add outside air through the drier. What you ask will work on your year coach but you might be introducing moisture the the tanks.
1999 40 ft. U-320 wtfe build 5563 Chuck & Lynda's "Rollin' Inn"  2030 watts solar
prev. mh's 71 GMC 5 yrs. 73 Pace Setter 1 yr. 78 Vogue 5 yrs 81 FTX 40ft all electric 18 yrs. 1996 Monaco Signature 3 yrs.
2014 Grand Cherokee Overland
Dream as if you will live forever. Live as if you will die today.  James Dean

Re: Adding air through the auxiliary outlet

Reply #2 –
Trying to figure out question 2,if the brake air is leaking down that means the coach is not moving and the engine not running,in
that setup the step is supposed to be down,it's been on other posts but none of these coaches are designed to hold air indefinitely,they all will leak down at different rates,instead of looking to add aux air work on the leaks and get them slowed down.
96 U270 BUILD 4810
85 380SL
Drummonds TN.

Re: Adding air through the auxiliary outlet

Reply #3 –
If you want to add air into your coach the best is to tee into the air line before the air
drier. I have done that so I don't have to start my engine when I need air when working
on the coach.
Peter and Frieda Morin
1999 36ft. U320 Foretravel
Build # 5436
1998 Suzuki Sidekick Sport

Re: Adding air through the auxiliary outlet

Reply #4 –

Two male air fittings bolted together with a shut off valve in between them. I keep it in the LP drawer with the tire gauge.My shop air line uses a different fitting then the coach. So the two bolted together are one of each.

Then add air through the female air chuck in the LP compartment. I have a drier on the compressor output in the shop. If your worried about moisture, add another one of these on the inlet piece you bolted together.
Chris


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Chris and Tammy White  CDA Idaho
Previous owners 1997 U295 36' 3126 Cat 300 HP Build # 4998
Former Foretravel tech & RVIA certified tech
Former owner Custom Satellite home/RV satellites 
Former owner Vans LTD  van conversions
Unemployed, panhandler, drag racer NHRA #6348

Re: Adding air through the auxiliary outlet

Reply #5 –
Different years have different systems. My '99 will air the front and rear air tanks through the auxiliary hose fitting. I know the '01's are different and only work the leveling system don't know about the 2000's
1999 40 ft. U-320 wtfe build 5563 Chuck & Lynda's "Rollin' Inn"  2030 watts solar
prev. mh's 71 GMC 5 yrs. 73 Pace Setter 1 yr. 78 Vogue 5 yrs 81 FTX 40ft all electric 18 yrs. 1996 Monaco Signature 3 yrs.
2014 Grand Cherokee Overland
Dream as if you will live forever. Live as if you will die today.  James Dean

Re: Adding air through the auxiliary outlet

Reply #6 –
The simple way to answer both questions:  TRY IT. 

Make up a male-male adapter.  Let the dash air pressure gauges get down to your "normal" 40-50 psi.  Connect air compressor hose to your tire filler hose.  Turn on compressor - see what happens.  Your dash air pressure gauges will either go up, or they won't.  Question answered.

Regardless of the answer, you would be better off taking the suggestion to "T" into the line between engine air compressor and air dryer.

1993 U280 SE 40' WTBI, Build: 4359
C8.3 300hp, 6-Speed, Exhaust Brake
960 watts on the roof (6 x 160)
Sorento (or BOLT) on a Kar Kaddy SS
"Nature abhors a vacuum"

Re: Adding air through the auxiliary outlet

Reply #7 –
 "However, apparently your air step has been modified from factory, as they were designed to stay down with the key off. "

Possible someone has done the Barry Beam step mod?
Might look for a toggle switch in the bay adjacent to the door, worth a look anyway.

Frank & Connie Williams
1999 U320 '36
Build: 5466
MC: 18335

Re: Adding air through the auxiliary outlet

Reply #8 –
They may have changed the way the Aux Air connection works when slides were introduced.  Mine gets air from the HWH compressor and adds air to the leveling system.  It does not add air to the service or wet tanks or to the HWH tank or bladder sealing system.  Find your air system diagram and follow the flow. Pay attention to check valves. 

I added this to my coach, very effective and helpful if you are chasing air leaks.
External Compressor Connection to Add Air to Wet Tank and Service Tanks
Roger Engdahl and Susan Green
2001 U320 3610 #5879 (Home2) - 2014 Jeep Cherokee or 2018 F150
Hastings, MN

Re: Adding air through the auxiliary outlet

Reply #9 –
Pyolet
I modified the wiring as per a different post so the step was in the closed position anytime the door was closed. Iit was an easy mod  I kinda like it up when the door is closed and the engine is off. When it opens down with the air tank drop it actually is disappointing!  I know..a little daft..
Peter    Alberta Canada
'98 U320 40'  Build 5359 M11 450 HP, Aqua hot, Blu Ox

Re: Adding air through the auxiliary outlet

Reply #10 –
Quote from: craneman –
Different years have different systems. My '99 will air the front and rear air tanks through the auxiliary hose fitting. I know the '01's are different and only work the leveling system don't know about the 2000's

Chuck
Our 1997, fills all the tanks.
Chris
Chris and Tammy White  CDA Idaho
Previous owners 1997 U295 36' 3126 Cat 300 HP Build # 4998
Former Foretravel tech & RVIA certified tech
Former owner Custom Satellite home/RV satellites 
Former owner Vans LTD  van conversions
Unemployed, panhandler, drag racer NHRA #6348

Re: Adding air through the auxiliary outlet

Reply #11 –
Quote from: Chuck & Jeannie –
The simple way to answer both questions:  TRY IT. 

Make up a male-male adapter.  Let the dash air pressure gauges get down to your "normal" 40-50 psi.  Connect air compressor hose to your tire filler hose.  Turn on compressor - see what happens.  Your dash air pressure gauges will either go up, or they won't.  Question answered.

Regardless of the answer, you would be better off taking the suggestion to "T" into the line between engine air compressor and air dryer.

Did that and filled both tanks with the tire filler outlet. Protection valves work on my coach also. Don't know if there is a check valve somewhere not functioning or this is the way my coach was plumbed.
1999 40 ft. U-320 wtfe build 5563 Chuck & Lynda's "Rollin' Inn"  2030 watts solar
prev. mh's 71 GMC 5 yrs. 73 Pace Setter 1 yr. 78 Vogue 5 yrs 81 FTX 40ft all electric 18 yrs. 1996 Monaco Signature 3 yrs.
2014 Grand Cherokee Overland
Dream as if you will live forever. Live as if you will die today.  James Dean

Re: Adding air through the auxiliary outlet

Reply #12 –
Quote from: craneman –
Don't know if there is a check valve somewhere not functioning or this is the way my coach was plumbed.
You don't have the air system schematic for your coach?

1993 U280 SE 40' WTBI, Build: 4359
C8.3 300hp, 6-Speed, Exhaust Brake
960 watts on the roof (6 x 160)
Sorento (or BOLT) on a Kar Kaddy SS
"Nature abhors a vacuum"

Re: Adding air through the auxiliary outlet

Reply #13 –
I did have just not in my binder and don't have time to search where I might have moved it to. Not an issue at this time and I know it will show up. Bad habit of bringing things in the house to study them.
1999 40 ft. U-320 wtfe build 5563 Chuck & Lynda's "Rollin' Inn"  2030 watts solar
prev. mh's 71 GMC 5 yrs. 73 Pace Setter 1 yr. 78 Vogue 5 yrs 81 FTX 40ft all electric 18 yrs. 1996 Monaco Signature 3 yrs.
2014 Grand Cherokee Overland
Dream as if you will live forever. Live as if you will die today.  James Dean

Re: Adding air through the auxiliary outlet

Reply #14 –
Here is one for your computer
Peter and Frieda Morin
1999 36ft. U320 Foretravel
Build # 5436
1998 Suzuki Sidekick Sport

Re: Adding air through the auxiliary outlet

Reply #15 –
Quote from: oldguy –
Here is one for your computer
Thanks Peter,

 It shows the 3/8 air line going straight into the wet tank no check valve. Mine is factory plumbed that way.
1999 40 ft. U-320 wtfe build 5563 Chuck & Lynda's "Rollin' Inn"  2030 watts solar
prev. mh's 71 GMC 5 yrs. 73 Pace Setter 1 yr. 78 Vogue 5 yrs 81 FTX 40ft all electric 18 yrs. 1996 Monaco Signature 3 yrs.
2014 Grand Cherokee Overland
Dream as if you will live forever. Live as if you will die today.  James Dean

Re: Adding air through the auxiliary outlet

Reply #16 –
Quote from: craneman –
It shows the 3/8 air line going straight into the wet tank no check valve.
Same exact setup on our '93 model, so must have been pretty standard all through the 90's models.

I have my 120V air compressor permanently mounted in the big central storage bay, connected with a "T" into that air filler hose line.  I also have a water/oil filter canister on the compressor output line, so I am not putting "wet" air into my system.  Very handy being able to pressurize the coach air system anytime I want, without needing to start the big engine.

1993 U280 SE 40' WTBI, Build: 4359
C8.3 300hp, 6-Speed, Exhaust Brake
960 watts on the roof (6 x 160)
Sorento (or BOLT) on a Kar Kaddy SS
"Nature abhors a vacuum"

Re: Adding air through the auxiliary outlet

Reply #17 –
It is not a good idea to add air to the system without making sure it is dry.  This aux air port was for adding air to tires (coming out) and in an emergency a tow truck could connect air (going in) for ride height control while towing.

However yours works water in the air system is not good. 
Roger Engdahl and Susan Green
2001 U320 3610 #5879 (Home2) - 2014 Jeep Cherokee or 2018 F150
Hastings, MN