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Topic: Diesel fuel life ? (Read 682 times) previous topic - next topic

Diesel fuel life ?

I always add a conditioner and cetane booster when adding fuel. My FT has diesel in it from last summer. It sit's in an insulated shop all winter with monthly starts and short drives to operating temp. of 180. Should I siphon it out or will it be okay as I only will take a few trips this summer. It's 1/2 full and where I'm going that will be enough
Thanks
1996 U295-36, Cummins 300hp, 8.3. Build number 4864. Vin number 1F97D536XTNO54271. Purchased October 31, 2019.

Re: Diesel fuel life ?

Reply #1 –
Our U300 has diesel in it from a lot longer than that. Also have a 300SD that rarely gets driven. Our 500 gallon tractor diesel tank has 30 year old diesel in it that the tractor and generator love. Think it will last forever. Some of the sweet crude oil is good enough to go into huge diesel engines and has been in the ground for millions of years. The additives in diesel today won't last that long and the diesel may go out of emission specs but the engines will start and run fine.

Pierce
Pierce and Gaylie Stewart
'93 U300/36 WTBI
Detroit 6V-92TA Jake
1140 watts on the roof
SBFD (ret)

Re: Diesel fuel life ?

Reply #2 –
Heavy equipment when not in use is parked for years and when needed again batteries
are put back in them and the usually start right up. so just use it. The best way to park is
to have the fuel tank filled right up.
Peter and Frieda Morin
1999 36ft. U320 Foretravel
Build # 5436
1998 Suzuki Sidekick Sport

Re: Diesel fuel life ?

Reply #3 –
Add a biocide now and good to go when needed.
Dan - Full timing since 2009
2003 U320 40' Tag 2 slide

Re: Diesel fuel life ?

Reply #4 –
I have an old tractor (1959) waiting on restoration. 🙄
It has 20 year old diesel in it and I crank it occasionally. Starts and runs fine.
Good filters and a additives to reduce algae.

Run it !!
 
Justin & Cathy Byrd
1995 U280 "Old Faithful"
36' Build #4673
C8.3 Cummins
Allison MD3060R 6 speed - retarder
Powertech 10KW  4cyl Kubota

Re: Diesel fuel life ?

Reply #5 –
The answer on diesel fuel longevity is IT DEPENDS.

In your case, smell it.  if it smells like diesel, it is probably OK.  The second "test" is after driving the first time, check the primary fuel filter for evidence of algae.

Now, the "best practices" for diesel storage:

Minimum biodiesel percent you can find.
Add a BIOCIDE such as Biobar JF.  Then fill tank (to minimize condensation) and both drive and run generator long enough to get treated fuel circulated.

If storing less than 2 months in summer or 3 months in winter, just filling the tank is sufficient. Algae only grows at a water/diesel interface.  No water, no algae.
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020

Re: Diesel fuel life ?

Reply #6 –
WE have no humidity here, so algae is not an issue thank goodness.
Thanks
1996 U295-36, Cummins 300hp, 8.3. Build number 4864. Vin number 1F97D536XTNO54271. Purchased October 31, 2019.

Re: Diesel fuel life ?

Reply #7 –
Quote from: dans96u295ft –
WE have no humidity here, so algae is not an issue thank goodness.
Thanks

Really?  So temperature never gets down to the DEW POINT?

Areas with very wide temperature fluctuations, even dry areas, are prone to condensation issues. If you have, say 50 gallons of air in the tank, as temperatures rise during the day, that air expands and escapes the tank.  Then as temperatures decline, it is sucked back into the tank.  The more extreme the temperature fluctuation, the more "new" air is introduced to the tank. No aware of any area where the temperature does not drop occasionally to the dew point where condensation occurs.
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020

Re: Diesel fuel life ?

Reply #8 –
There are instructions on the back of the Biobor JF bottle on how to "shock" the tank. I'd do that, then go fill up the rest of the tank. I'd  make sure I have a few extra sets of fuel filters with me on my first trip too.
1987 Grand Villa ORED
2001 U320 4010

Not all that wander are lost... but I often am.

Re: Diesel fuel life ?

Reply #9 –
Quote from: wolfe10 –
Really?  So temperature never gets down to the DEW POINT?
Quite correct as you can dig a shallow depressing in desert sand, stretch a piece of plastic over it with a small rock in the middle and a container under the plastic and collect water after a day.

Here is the weather in Death Valley as I type this post. It's 80 degrees with the humidity at 21% and the dew point at 37 degrees. Not likely to get down to the dew point today but in a different season, it will.

That's why I never fuel aircraft or motorhome in above ground fuel tanks unless there is no option. As fuel is used from the tank, it's replaced by air. Air with some or a lot of humidity. When the temperature drops to the dew point in the tank, condensation forms and runs down the wall of the tank collecting at the bottom. Warm weather and water in the tank make a perfect environment for algae growth. In warm weather, pour a drink with ice cubes in a glass and watch the condensation form on the outside of the glass. It didn't come through the glass.

Pierce
Pierce and Gaylie Stewart
'93 U300/36 WTBI
Detroit 6V-92TA Jake
1140 watts on the roof
SBFD (ret)

Re: Diesel fuel life ?

Reply #10 –
Never even seen algae additive here, even at truck stops. Don't have the issue, sorry
1996 U295-36, Cummins 300hp, 8.3. Build number 4864. Vin number 1F97D536XTNO54271. Purchased October 31, 2019.

Re: Diesel fuel life ?

Reply #11 –
Not much humidity in Colorado as a general rule, regularly see it in single figures, most times when the dew point meets the temperature it's snowing. For me the best thing for the winter is cetane boost and fill the fuel tank before I park. Sunday I'll fire up the coach and move to the flat part of the driveway and start preparing to head out. When I park for the winter that part of the driveway allows the coach to sit slightly lower towards the drivers side rear.
88 Grand Villa 36' ORED 3208 (throwaway)Cat.
 Build # 3150
Happiness is the maximum agreement of reality and desire.

Re: Diesel fuel life ?

Reply #12 –
Quote from: dans96u295ft –
Never even seen algae additive here, even at truck stops. Don't have the issue, sorry

Makes perfect sense.  Trucks do not STORE diesel.

Boats and motorhomes DO.
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020

Re: Diesel fuel life ?

Reply #13 –
Quote from: dans96u295ft –
Never even seen algae additive here, even at truck stops. Don't have the issue, sorry
But when you take a trip of any length, you fuel at a station with no real idea of the quality. Probably good but the U.S. does not have strict standards or regular inspections at service stations. That's why I have to laugh at the owners who throw $$$ at the fuel polishers to get a nice clean tank. Just like washing your car before heading down the highway in spring time. Just a different kind of bug.

That's why I put a gallon of anti-bug next to the diesel fuel tank. Diesel fuel also changes from season to season so summer diesel may have a different formulation compared to winter diesel. A Cetane boost additive may help starting in winter. Straight USLD Ultra Low Sulfur Diesel (ULSD): the Good, the Bad, and the Rusty does not have the lubricity of the old sulfur diesel and with the high pressure common rail fuel systems installed today, increased wear in the injection system as well as the engine itself is a risk. Biodiesel will help with the lubricity but having an additive that addresses the algae, Cetane and lubricity is never a bad idea.

Pierce
Pierce and Gaylie Stewart
'93 U300/36 WTBI
Detroit 6V-92TA Jake
1140 watts on the roof
SBFD (ret)
 

Re: Diesel fuel life ?

Reply #14 –
Above is true especially if you have the Bosch mechanical injection system.
96 U270 BUILD 4810
85 380SL
Drummonds TN.