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Author Topic: Parked for several months at a time  (Read 343 times)


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Parked for several months at a time
« on: October 12, 2018, 07:21:47 AM »
Good Morning,

We are camp hosts and spend our winter months in a warm area hosting. This year our motor home (Cummins 5.9 ISL) will be parked at a site for 3 to 4 months. I have filled the fuel tank but was wondering about any fuel additives when parked this long. How about DEF should it be filled to complete full? Any additives for it? We exercise the genset every 11 days - auto gen start. We have our tires covered and a wax was done several days ago. Have I missed anything?

Marshall and Marcie - Full Timers
2013 Coachmen Pathfinder Touring Edition
360 HP Cummins ISB
2016 Colorado Z71 Toad
Shin Tzu Navigators Louis and Abby

Gary RV_Wizard

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Re: Parked for several months at a time
« Reply #1 on: October 12, 2018, 10:04:29 AM »
Keeping the tanks full reduces moisture from condensation, so is a Good Thing.

In a warm humid climate I might add a biocide to the diesel fuel just to be sure no algae grows, but that is just extra insurance. Diesel algae is not typically a problem during the winter months anyway. A diesel biocide product would be something like Biobor JF or Killem.

I know of no treatment needed or available for DEF.  It isn't fuel and never gets inside your engine. It has a shelf life of about 2 years, so it should be fine unless it was already old when you bought it.
Gary Brinck
Summers: Black Mountain, NC
Home: Ocala National Forest, FL


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Re: Parked for several months at a time
« Reply #2 on: October 12, 2018, 10:35:14 AM »
 Your Cummins is also an ISB (if it's 5.9 liter) not ISL.>>>Dan
Vary rare American Tradition 38TT/330 turbo Cummins
Last year Jeep liberty 4 down
72 VW Baja 4 down
Cedar City, Utah
USAF vet. 59-63
FMCA F312919
The difference between intelligence & stupidity is: intelligence has it's limits
      Albert Einstein.


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Re: Parked for several months at a time
« Reply #3 on: October 12, 2018, 11:41:50 AM »
Will your motorhome be plugged in at that site? Even at 3-4 months it would be a good idea to plug in for the sake of the batteries.



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Re: Parked for several months at a time
« Reply #4 on: October 12, 2018, 01:22:36 PM »
  Add some Biobor-JF to prevent algae. https://www.amazon.com/gp/product/B0014434DG/ref=oh_aui_detailpage_o00_s00?ie=UTF8&psc=1

  Also if it's going to get really cold anti-gel wouldn't hurt.

  If your MH doesn't charge the starter battery when plugged in a charger/maintainer would be good.