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Topic: Dash controls (Read 358 times) previous topic - next topic

Dash controls

So I got my ac cold and working. Thanks for all your help in this. Now I can't seem to get the controls to change from dash to floor.
I'm wondering if the vacuum thing in the step well has something to do with it. I'm not sure how this works or it even works. It is  leaking air.
The following photos the parts and does any on know what it controls and how it works.
Thanks again
James and Suzi
1999 U320  36, Cummins M11
Build 5544  Motorcade #17268
Ronan, Montana
2020 Jeep gladiator

Re: Dash controls

Reply #1 –
obsolete vacuum generator
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: Dash controls

Reply #2 –
Ok so it's an obsolete vacuum generator. Does any one know how it works and what it operates?
I would like to possibly fix it. I do notice that air is coming in from the large hose that comes into the step well and I'm assuming that the air goes through the generator and vacuum goes back through the small line to the dash?
James and Suzi
1999 U320  36, Cummins M11
Build 5544  Motorcade #17268
Ronan, Montana
2020 Jeep gladiator

Re: Dash controls

Reply #3 –
Quote from: Gold Nugget finder –
Ok so it's an obsolete vacuum generator. Does any one know how it works and what it operates?

How Dash Air Works - U320

Dash Air Stuck on Defrost/Vacuum Pump Replacement

Vacuum Generator finally quit
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: Dash controls

Reply #4 –
A couple years difference in our coaches, so I'm not sure the system was the same in '99...but mine was made by SGM - there was a sticker in the dash of mine.  They furnished me a diagram.  If yours is the same, here it is.  If not, and it is a SGM provided system, contact them - I bet they have the schematic for yours too.

https://sgmcoinc.com/
Keith
2003 U320 38' #6197

Re: Dash controls

Reply #5 –
Quote from: Gold Nugget finder –
I'm wondering if the vacuum thing in the step well has something to do with it.
Most likely yes, that is your vacuum source to control the dash/floor actuators in the dash area.

You can see the two actuators (driver and passenger) when you lift up the center console.  If you want to test them you can detach the line leading to one and give it the old straw suck, it will take very little vacuum to open them up.

Here are some details for the 2000 model

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If those actuators work, and you are getting 12V down to the black box in the step well (and you have pressure in your air tanks) , then that is most likely your problem.  My understanding is that when the system opens the solenoid, it expels air,  which causes a venture effect on that plastic check valve, which allows vacuum to build up in the coffee can canister.  Its told to turn on/off by that vacuum relay (in your picture 4)

The most common issues are:
1) The one way check valve as failed, replace it or clean it (in your picture it appears to be the yellow plastic part, in the picture I've attached its the blue one) You should be able to blow air through it in one direction only.
2) The coffee can vacuum reservoir has developed a leak(s), patch it with some JB Weld
3) The vacuum on/off sensor has failed and never tells the solenoid to open, replace it

On mine, the air hoses are quick connects, just push/pull the collar and slide the hose out, easier to work on this when its on the bench.
2000 / 36' / U320 / WTFE
WildEBeest / "Striving to put right what once went wrong"

Re: Dash controls

Reply #6 –
Quote from: Gold Nugget finder –
Ok so it's an obsolete vacuum generator. Does any one know how it works and what it operates?
I would like to possibly fix it. I do notice that air is coming in from the large hose that comes into the step well and I'm assuming that the air goes through the generator and vacuum goes back through the small line to the dash?
Did you read the text? I repaired mine with the information I provided. The large hose has air pressure from the coach when the ignition is turned on. It makes vacuum by venturi effect and goes to the reserve can which then goes to the dash controls. If the check valve fails you don't get vacuum. You can also buy 12 volt vacuum pumps listed in the links on the forum.
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: Dash controls

Reply #7 –
Thanks for all your help.
I've ordered the new system and plan on replacing the old stuff.
James and Suzi
1999 U320  36, Cummins M11
Build 5544  Motorcade #17268
Ronan, Montana
2020 Jeep gladiator