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Topic: airing up bags without starting the engine (Read 777 times) previous topic - next topic

airing up bags without starting the engine

Can I just turn the HWH on, on the dash and level up. It's plugged into power. I don't want to start the diesel in the winter for short time frames without driving it to full temperature. My mechanic used Locktite 545 sealant on the new airbags and ride height valves and so far I've had 3 leaks in three different areas. He needs to take a plumbing course.
1996 U295-36, Cummins 300hp, 8.3. Build number 4864. Vin number 1F97D536XTNO54271. Purchased October 31, 2019.

Re: airing up bags without starting the engine

Reply #1 –
I have to turn on the ignition to power the HWH panel but do not need to start the coach.  You will need your 12V compressor to supply air.

Rich
Rich and Peggy Bowman
2002 U270 3610 WTFS, build #5939--"Freedom"
2022 Jeep Grand Cherokee Summit 4xe
SMI AirForceOne brake system
PakCanoe 15

Re: airing up bags without starting the engine

Reply #2 –
No problem, that's what the 12-volt air compressor is designed to do after your tank air is exhausted. Press the air button on HWH pad one time then level manually or press it twice and it will automatically level.  Shouldn't be any need to turn your ignition on.
Doug W.
96 36' U270 CSGI #4946
04 Toyota Tacoma 4x4
PNW

Re: airing up bags without starting the engine

Reply #3 –
Think he just needs to test for leaks when he finishes a job like that,why would you not test for leaks,if your tightening brass to brass
you don't even need any sealant as the brass is soft enough to seal itself.
96 U270 BUILD 4810
85 380SL
Drummonds TN.

Re: airing up bags without starting the engine

Reply #4 –
If your HWH pad is off you need to turn on the ignition to press the AIR button once for manual leveling ot twice for automatic leveling.  Once the HWH panel is on you can turn off the igntion.

With no slide you (should) have no slide air tank so the air from the small compressor goes to the leveling manifolds and then to the air bags.  The need about 90 psi to do anything so your small compressor needs to be working well and developing the needed pressure.

If you have an external compressor you can connect it to the aux air connection (mine is in the LP compartment) using a male to male adapter.  This air will go to the leveling manifolds and then to the air bags and with the HWH panel enabled allow you to level or raise the coach.  You don't want to introduce moisture into the system so use an inline water separator as well.

Double check your air system schematics. This works if the check valves are working correctly and the air system hasn't been modified from original.
Roger Engdahl and Susan Green
2001 U320 3610 #5879 (Home2) - 2014 Jeep Cherokee or 2018 F150
Hastings, MN

Re: airing up bags without starting the engine

Reply #5 –
If you want to air up the wet tank and the service tanks and thus the leveling system without running the coach's engine then add an external air connection just ahead of the coach air dryer.  It will work just like the engine air compressor does and use the air dryer to provide dry air.  It is quite handy when chasing air leaks or if you just want to air up the coach.

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: airing up bags without starting the engine

Reply #6 –
I put an air tool fitting on my wet tank drain. If I need to fill it with air I just hook my garage air compressor right up to the coupler and open the drain valve super slow, not all the way open. A slow fill is better.
92 Grand Villa
Silver 6v92
 side isle.
build# 3973

Re: airing up bags without starting the engine

Reply #7 –
Ok. Great info. I'll try the 12 volt method. Be the 3rd visit back to my shop since they installed the bags and ride valves. Really disappointed with his work on the air sealant part.
Thanks again
1996 U295-36, Cummins 300hp, 8.3. Build number 4864. Vin number 1F97D536XTNO54271. Purchased October 31, 2019.

Re: airing up bags without starting the engine

Reply #8 –
I went to level my coach in storage, as per the suggestions in this post by just turning on the ignition. I noticed that the brake air pressures were at zero. I turned on the ignition, pushed the HWH once, (the red light came on) and heard the air compressor come on. After pushing the level button again for dumping/auto level I did not notice anything happening.
After several minutes I ended up turning off the ignition and HWW, and then started the engine. After the air pressure came up I started the HWH process again. This time it worked perfectly.
Suggestions as to why it would NOT work with JUST the ignition on, and the engine not started???
Peter
Peter    Alberta Canada
'98 U320 40'  Build 5359 M11 450 HP, Aqua hot, Blu Ox
 

Re: airing up bags without starting the engine

Reply #9 –
The HWH system will not do much until you get the system up to 90 psi or more.  If air has leaked out of the leveling system it can take some time.  The HWH system and the small compressor are isolated from the service tanks by check valves.  The HWH compressor will not put air into the service tanks (unless you check valves are toast) but air from the service tanks will add air to the leveling system.

If your coach is winterized and nothing is running not being perfectly level is not a problem.
Roger Engdahl and Susan Green
2001 U320 3610 #5879 (Home2) - 2014 Jeep Cherokee or 2018 F150
Hastings, MN