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Topic: Desiccant air dryer in line with the 12 v air compressor (Read 842 times) previous topic - next topic

Desiccant air dryer in line with the 12 v air compressor

Wise Ones,
I searched for this topic and read all the posts I could find.  I went to check on the desiccant in our 2001 U320.  There is no deiccant bowl after the first filter and water collector with the purge solenoid at the bottom.  I looked at the pictures posted by Michelle.  The first bowl is there.  I took it ll apart and it look clean.  The second bowl is simply not there.

I also looked at the wiring diagram for the aux compressor.  It shows a dash switch to to turn on the compressor, open a soloniod valve and precharge the air system before starting the engine (or to use air to fill a tire for example).  No so in my 2001. 

Is this something that came after the 2001 models?  I ordered the desiccant bowl and desiccant and am going to add that in after the first filter.  Seems like a good idea to dry the air.  What do I need to add to enable the precharge functionality?

Your guidance is always appreciated.

Roger

Roger Engdahl and Susan Green
2001 U320 3610 #5879 (Home2) - 2014 Jeep Cherokee or 2018 F150
Hastings, MN

Re: Desiccant air dryer in line with the 12 v air compressor

Reply #1 –
Recall my build number next to yours.  Was at a park in NM and there was a desire to use the auxiliary switch, not to avoid bothering neighbors with engine compressor, but to address another problem.  Happened a FT expert came by, looked for the switch you were seeking....I do not have one either, so you not alone.  I understand it came either after 2001 or just not on all 2001s.

I checked on adding another moisture control, such as desiccant, to the condense and exhaust bowl and was advised by technician it not needed.  I am not advocating that, but couple of expert types tried to dissuade me to spending money to add the desiccant.  They won!

Hope this helps,

Mike
Mike
2001 U320 4010 Build 5878 (Gus)
Wrangle Unlimited Toad
Nacogdoches

Re: Desiccant air dryer in line with the 12 v air compressor

Reply #2 –
I think if the aux pump pre-charge function is added then it would be important to push dry air into the main air tanks and plumbing.  The desiccant bowl and spare desiccant was about $75.  Other than an older person crawling into the basement (imagine that for a moment) it shouldn't be too hard too add.

I need to figure out what solenoid valve to add where and the wiring to a switch.

Roger
Roger Engdahl and Susan Green
2001 U320 3610 #5879 (Home2) - 2014 Jeep Cherokee or 2018 F150
Hastings, MN

Re: Desiccant air dryer in line with the 12 v air compressor

Reply #3 –
My aux did in fact have to try to fill the main tanks due to failed check valves.  The result was that that small compressor was trying to replace the large engine compressor in filling the tanks.  In turn it ran a very long time, got so hot I unplugged it before even got all the tanks up to 60 psi.

In may be that is permissible, I do not know but I had been adorned, do not overdo running it, burning out that small compressor is expensive.  Even so, some coaches are designed, as by evidence of the switch, to be used for such service.  Maybe my aux would have handled it, maybe not and that was why I do not have the option on mine?

Just giving some food for thought, not a final answer or guidance.  Hope others pick up on this thread, give us input.

Mike

Mike
2001 U320 4010 Build 5878 (Gus)
Wrangle Unlimited Toad
Nacogdoches

Re: Desiccant air dryer in line with the 12 v air compressor

Reply #4 –
Found an air leak in solenoid #2. Which opens when the foretravel dash switch is on. Found it labeled as solenoid #2, but can not find the part number on any of the schematics or diagrams. Does anyone know the part number? Have attached pictures.
Ellen
2005 U320  4030 PBTS
2017 GMC Acadia
MC # 16978

Re: Desiccant air dryer in line with the 12 v air compressor

Reply #5 –
Quote from: ems3135 –
Found an air leak in solenoid #2. Which opens when the foretravel dash switch is on. Found it labeled as solenoid #2, but can not find the part number on any of the schematics or diagrams. Does anyone know the part number? Have attached pictures.
Looks like an RAP91893
The selected media item is not currently available.Barry BEAM #16014
2003 U320 40' AGDS
Beamalarm, Foretravel technical help and specifications
"Whatever the mind can conceive and believe, it can achieve"

Re: Desiccant air dryer in line with the 12 v air compressor

Reply #6 –
Thanks  very much! You are very helpful! ^.^d
Ellen
2005 U320  4030 PBTS
2017 GMC Acadia
MC # 16978
 

Re: Desiccant air dryer in line with the 12 v air compressor

Reply #7 –
You all realize, don't you, that Barry is not a real live human person.  Just like Apple iPhones have SIRI, we have BARRY, an artificial intelligence computer program that resides in the cloud.

Just kidding, I met the real Barry, nice guy, and he looks just like his photo, hat and all.  His intelligence is not AI.
Tom Lang K6PG (originally  KC6UEC)
and Diane Lang
2003 38 U295 build 6209
2016 Jeep Grand Cherokee Summit Ecodiesel
still have tow-ready 2006 Acura MDX 
Temple City, California
Motorcade 16681 California Chapter President
SKP 16663 member of SKP Park of the Sierra, Coarsegold California
FMCA F071251
Retired electrical and electronic engineer