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12 Volt Compressor

My 12 volt compressor in the storage bay just kept running, but didn't sound right. Took it out and pulled it apart and found the small piston "ring" had came apart.  It is a Thomas 405adc38/12.  They have a rebuild kit for about $200.  This is the second Thomas compressor that has gone bad on me.  Was wondering if anyone had any experience with other brands ?

I was looking at the Viair 350C. It is a 100% Duty Cycle compressor that looks like it would fit nicely.  Seems to put out plenty of volume, and the whole unit costs the same as a rebuild kit for the Thomas.

Any suggestions ?
Mark & Bev
2001 U295 36' Slide
Cummins ISC 8.3 350HP
Build #5802
Jeep Wrangler Toad

Re: 12 Volt Compressor

Reply #1 –
Don (Don & Tys) replaced his Thomas with a ARB compressor.  I believe he has been pretty happy with it.  He may see this thread and chime in.  Link below to his install thread.

HWH lung transplant (or aux compressor upgrade)
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: 12 Volt Compressor

Reply #2 –
This is the one used from 2002 on.  1/3 HP this price is typical. I found a new one for about $900.
THOMAS 1/3 hp HP Piston Air Compressor, 12V DC, -/100 Max. PSI Cont./Int. -...

Rebuild kit worked fine on my smaller compressor, it cost about $100, $200 now.

Lots of choices,  I think you get what you pay for here.  The Viair compressors don't last. Hdff has one that seems to have failed.

If you can use a 120v version they are much cheaper.  It is worth considering.
Roger Engdahl and Susan Green
2001 U320 3610 #5879 (Home2) - 2014 Jeep Cherokee or 2018 F150
Hastings, MN

Re: 12 Volt Compressor

Reply #3 –
It still works like a champ... I am able to use it to raise the whole coach high enough to get my 12" frame blocks in. It has been rock solid, been used a lot, and I would buy it again. ^.^d
Don.
Quote from: Chuck & Jeannie –
Don (Don & Tys) replaced his Thomas with a ARB compressor.  I believe he has been pretty happy with it.  He may see this thread and chime in.  Link below to his install thread.

HWH lung transplant (or aux compressor upgrade)
The selected media item is not currently available.
Don & Tys
1999 U270 3602 WTFE #5402
Xtreme Stage 1 w/Headlight, Step Conversion, etc.
2009 Honda Fit Sport with Navi
Freedom is NOT "just another word for nothing left to lose"... with apologies to Kris Kristofferson

Re: 12 Volt Compressor

Reply #4 –

I think this is what Don used,  Looks like a good alternative to either of the Thomas compressors.
Amazon.com: ARB CKMTA12 '12V' On-Board Twin High Performance Air Compressor:...
Amazon seller's price is about what everyone sells them for.  Nice to get a wiring harness if you need it.

68 amp max load.

As an Amazon Associate Foretravel Owners' Forum earns from qualifying purchases.
Roger Engdahl and Susan Green
2001 U320 3610 #5879 (Home2) - 2014 Jeep Cherokee or 2018 F150
Hastings, MN

Re: 12 Volt Compressor

Reply #5 –

That is the one! I bought it from an Off Road Warehouse for near that price and I just saw the ARB dual compressor on display at another 4X4 store yesterday. I think that the 68AMP load Roger quotes is the locked rotor specification. I have seen it typically draw between 40 and 50AMPS while running. The LRA must be over to quickly to register on my Magnum ARC50 remote...
Don

Quote from: Roger & Susan in Home2 –
I think this is what Don used,  Looks like a good alternative to either of the Thomas compressors.
Amazon.com: ARB CKMTA12 '12V' On-Board Twin High Performance Air Compressor:...
Amazon seller's price is about what everyone sells them for.  Nice to get a wiring harness if you need it.

68 amp max load.
As an Amazon Associate Foretravel Owners' Forum earns from qualifying purchases.
The selected media item is not currently available.
Don & Tys
1999 U270 3602 WTFE #5402
Xtreme Stage 1 w/Headlight, Step Conversion, etc.
2009 Honda Fit Sport with Navi
Freedom is NOT "just another word for nothing left to lose"... with apologies to Kris Kristofferson

Re: 12 Volt Compressor

Reply #6 –
Don, did you have to upgrade the existing wiring for the ARB ?
Mark & Bev
2001 U295 36' Slide
Cummins ISC 8.3 350HP
Build #5802
Jeep Wrangler Toad

Re: 12 Volt Compressor

Reply #7 –
LRA event usually 200-300 microseconds
Tim Fiedler    2025 LTV Unity MBL on Order
2000 Chevy Tracker 2 Door Convertible 4WD Now lifted 4.5"
1985 Citroen 2CV6 Charleston
Murphy Rebel on wheels with 175HP Titan
Cessna P337
1980 48' Westport MY (!/4 Share)

Re: 12 Volt Compressor

Reply #8 –
Is the item pictured the old style pressure switch for the compress ? And can it be replaced with a new style like Shown below from Amazon?
Mark & Bev
2001 U295 36' Slide
Cummins ISC 8.3 350HP
Build #5802
Jeep Wrangler Toad

Re: 12 Volt Compressor

Reply #10 –

Mark, Maybe.  This is the one that I used.
Square D by Schneider Electric 9013FHG2J27 Air-Compressor Pressure Switch,...
There are others out the that will work.

The compressor comes on when the Essex relay is actuated.  That might be by a switch, by the HWH computer or the pressure switch.

Different years are wired differently.

As an Amazon Associate Foretravel Owners' Forum earns from qualifying purchases.
Roger Engdahl and Susan Green
2001 U320 3610 #5879 (Home2) - 2014 Jeep Cherokee or 2018 F150
Hastings, MN

Re: 12 Volt Compressor

Reply #11 –
Thank you Roger, I was looking at that one too, just was curious if the other smaller style would work.  Just trying to clean up the wiring in the area.  The PO had quite the nest of cut and spliced wires in there. 
Mark & Bev
2001 U295 36' Slide
Cummins ISC 8.3 350HP
Build #5802
Jeep Wrangler Toad

Re: 12 Volt Compressor

Reply #12 –
Mark, I used the shelf brackets in my 2001 for my bigger compressor and the Essex relay. It is all mounted on a 1" baltic birch board.  Pretty easy to do the setup on the bench, install and make final connections.

I moved everything else to a panel assembled on the bench and then bolted to steel framing on the bay wall. I added a dryer and a second filter, an air pressure gauge and a solenoid to add air to the wet tank like the 2003 coaches.  Wiring at the driver's side panel adds a compressor on/off and if it is on the wet tank solenoid valve.

All of the parts on the back wall of the bay makes service easy.

The ARB compressor would work this way.
Roger Engdahl and Susan Green
2001 U320 3610 #5879 (Home2) - 2014 Jeep Cherokee or 2018 F150
Hastings, MN