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Topic: HWH air leveling (Read 666 times) previous topic - next topic

HWH air leveling

The right side of my coach is sitting low. My tank air pressure gauge reads 60 lbs. I want to level by pumping up the right side rather than let air out the left side. The problem is........with the "raise" button held in on the control panel, the 60psi Bendix relief valve attached to the cruise control panel vents off the air thus disallowing the airbags to inflate

So the question is, how can you raise the low side using the 12V compressor if the tank pressure is 60 lbs? Or raise it all around to work on it? Is something broke?

Apparently the relief valve is for the Bendix Cruise Control so I assume that perhaps the valve is kaput?
1994 U280, Build 4490
Deming, NM.

Re: HWH air leveling

Reply #1 –
Quote from: Twig –
The problem is........with the "raise" button held in on the control panel, the 60psi Bendix relief valve attached to the cruise control panel vents off the air thus disallowing the airbags to inflate

What "relief valve" attached to what "cruise control panel"?  Are you talking about the cruise control stalk on the steering column?
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: HWH air leveling

Reply #2 –
That's your cruise control controller. The actual cruise control is on the firewall in the engine compartment. There is a 60 psi relief valve attached to it which limits the air pressure of the cruise control at 60 psi, not 110 that is in the tanks. This is where the air bleeds out when I activate the "raise" function of the HWH touch pad. Providing you have a Bendix cruise control.
1994 U280, Build 4490
Deming, NM.

Re: HWH air leveling

Reply #3 –
OK - I understand now.  Below is a copy of my "marked up" Bendix cruise control & air throttle diagram from a previous thread.

Bendix Air Cruise Control

Where (exactly) is the air being exhausted on the Bendix panel?
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: HWH air leveling

Reply #4 –
In your diagram it is listed as RV-1 reducing valve, 60 psi, which is in fact a Bendix 282811. This is not a cruise control issue as it works fine. But when "raise" is pushed on the HWH control pad instead of the airbags raising the height it bleeds air out of this valve. Just wondering if the valve is bad or there is another issue.
1994 U280, Build 4490
Deming, NM.

Re: HWH air leveling

Reply #5 –
Looks to me like it must be a bad (or stuck) exhaust valve inside the RV-1 reducing valve.

The input to this valve (line #6) comes directly off the line going from 12V compressor to "rear" tank.  My air system schematic shows it tied into the line between a 1-way check valve and the "protection valve" at the tank inlet.  In other words, whatever pressure is in the rear tank should be on the "upstream" side of the RV-1 reducing valve, and the "downstream" side should be regulated down to 60psi.

This valve appears pretty simple, and they are proud of them, judging by the online prices.  You could try taking it apart, clean it up, reassemble and try it again to see if it works better.  Cut-away drawing at link below:

http://www.bendixvrc.com/itemDisplay.asp?documentID=2732
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: HWH air leveling

Reply #6 –
  277144 corresponds with 80psi out.  277544 is 110psi out.
The correct 282811 for 60psi out is $44.50 from Midwest Bus Parts.
Valves : Midwest Bus Parts, We Do More Than Bus Parts
The bottom of their home page reads:
We are so glad that we can say with utter honesty that in all our dealings we have been
pure and sincere, quietly depending on the Lord for His help and not on our own skills
-2 Corinthians 1:12, TLB

RV-1 and RV-3 Service Data seem to be the same:
http://www.bendixvrc.com/itemDisplay.asp?documentID=4444
Mogan David
1999 U295 36'

Re: HWH air leveling

Reply #7 –
I have one ordered. Will post the results. Very confusing to me since the psi for raising the level height MUST be way more than 60.
1994 U280, Build 4490
Deming, NM.

Re: HWH air leveling

Reply #8 –
Quote from: Twig –
I have one ordered. Will post the results. Very confusing to me since the psi for raising the level height MUST be way more than 60.
WHY?  it takes a while.
Mogan David
1999 U295 36'

Re: HWH air leveling

Reply #9 –
Quote from: Twig –
I have one ordered. Will post the results. Very confusing to me since the psi for raising the level height MUST be way more than 60.
My coach doesn't go to the travel height until I have 70 psi or more.

Roland
1993 U280 4341
2010 Jeep Liberty
The Pied Pipers

Re: HWH air leveling

Reply #10 –
Ok. The solution. I replaced the pressure relief valve on the Bendix cruise control. Now my aux compressor works as it should. SO, now that I am a somewhat HWH air leveling authority, I can say for some reason the air bags fill up through this valve. With the old valve I could hear air coming out whenever the aux compressor was on but now there is no air and the bags fill.

If you have a problem with the bags not filling with the 12V compressor look here first. Has nothing to do with engine compressor.
1994 U280, Build 4490
Deming, NM.