Old Fuel

[jimtaylorville]

Our 2009 Camelot has been sitting for 3 years in an unheated garage. In those 3 years, Engine run 20 minutes,  generator used 2 plus days during power outage at our house.  When parked,  tank was 100% full. We are now ready to use coach again.  Concerned about our oud diesel plugging filters,  shutting down Engine in worst possible place.  We do have 3 sets of fuel filters for eng, genny, and Aqua-Hot,  tools in the coach.  Should we drain fuel or go with the old diesel?  Thanks 

[joefromperry]

• Well, hopefully when you parked the coach you added Biobor (or similar). Probably a good idea to change fuel filters, but I would not drain the fuel unless it's bad with algae. After changing filters, checking battery levels, etc., start it up and evaluate. If it's pretty cold, you might need anti-gel, if it wasn't added. Good luck.

[Jetjockey]

 May depend on the where you last fueled. Most diesel at the pump is not a premium fuel. Some is just base number 2 with no additives at all. All diesel starts as base product and then the seller chooses what additives if any are put in.True premium fuels cost more and are priced to reflect that. To get the best premium fuels we have to search or have a jobber who delivers it to us. on the farm all our fuels are premium. premium fuels can have higher btu content and used to offset some of the cost when fuel was cheaper.I do not worry much about these sitting in storage. I have machines that have set from year to year or longer and never experienced storage problems. I know of local farmers who always by the cheapest fuel  they can find and continually have  injector and injector pump issues.

Over the road I assume none are premium and put stanadyne or something similar in when filling up. Not all additives are the same
. You could look in the tank to see if any algae was visible. It can float on top and look like moss. You could pull a sample and have it checked by a lab. There are those who do so who also do oil analysis. Good luck

Edited February 4 by Jetjockey
Spelling

[FishAR]

When I bought my Camelot it had been sitting for probably 8 years. Luckily for me it was full of fuel.

I stared into the tank with a flashlight, I drew some fuel out and looked at it. I decided to just go with it and changed the fuel filters. I had no fuel related problems.

I had a lift pump problem but it was a loose electrical connection, not fuel related. I ran the fuel out on our first trip to Florida in it 3 winters ago.

[jacwjames]

I would suggest taking it for a drive prior to your trip at least 100 miles to confirm everything is OK.  During the drive the fuel be stirred up in the tank, I'd go ahead and change the primary filter, when you pull the old filter dump the contents in a bucket and look for any signs of algae or contamination.  If you don't see any you might be OK.

Others have suggested additives for algae.  When I first bought our coach I had no records and don't know how long it been parked in Florida, it was a repo.  I did change fuel filters when I got home and carried spares.  The first year we had it we took a trip to AK, almost 15K miles.  When I got home I did a service including fuel filters.  The primary filter was almost choked off with algae, I wasn't having any problems but eventually I would have. 

So since then I've used BioBor on a regular basis.  When I park my rig I fill up the tank and use a combination of BioBor and Startron enzyme treatment,  Never had another problem.  In 2015 we took a long trip and I parked the rig and started working on building a new house.  STUPID me decided to do as much of the work myself so as a result the rig was parked with occasional moving for +4 years, although I did live in it at the new house site for +2 years moving as needed.  In 2019 I decided to start using fuel out of the tank for my tractor and ultimately pulled ~75 gallons out, I never saw any algae.  I went to fuel up at some point and pumped 85 gallons, again no problems. 

Since then my OEM lift pump started to leak, I ultimately decided to install a FASS transfer pump which as two filters on it.  It runs continuously and is polishing the fuel while driving.  I've changed the filters twice and only found small amounts of "stuff" but no signs of algae. 

[Ivylog]

In the 70s (and currently) I used off road (not premium) diesel that was 10 years old… it doesn’t go bad.

[Paul J A]

I would drain 4 quarts of oil out of the engine oil pan, and replace with;

 https://www.lucasoil.com/product/heavy-duty-oil-stabilizer/

Eliminates dry starts. 

[throgmartin]

I would fire it up and let it run till it reaches normal temp. Once it is warm, kick it up to high idle for a few minutes. If it doesn't stall then I would take it on a joy ride of about 20 miles or so. Change the primary fuel filter after you have driven it. I would not change it before hand as after you drive it the fuel will be stirred up and the filter will catch a lot of the sediment. No sense in changing the fuel filter prior to driving it as long as it runs OK in the driveway. Save yourself a filter and change it after you drive it.

In regards to algae - You will know if you have any as the engine will run like crap or stall or worse yet not start at all. Never store a coach without treating the fuel with a big healthy dose of Biobar.

[dl_racing427]

With the tank being full, you likely won't have any issues with water in the fuel.
If treated with a biocide and kept dry, diesel will last pretty much indefinitely.  It doesn't have the light aromatics that evaporate off like gasoline does.
I keep several hundred gallons of diesel at home for standby generator use.
I treat the vented tanks once a year, and what I have in sealed barrels I don't really do anything to.  No moisture means no algae can grow.

In your case, I'd add another dose of Biobor, take it for a drive to stir up any contaminants, and check your primary filter afterwards to see if it contains any significant sediment or algae.
Swap in a set of new filters and make sure you have a spare set, and you should be good to go.