How long will Commercial Bio-Diesel keep fresh in my truck's fuel tank?
I just put in a 20% blend and was planning on running 2 tanks of IT, then going to 50% for 2 tanks, then right to B99.
I use about a tank (38 gallons) per month in my '99 F350 7.3 truck.
My friens says the BIO will go bad way before regular Diesel will inside the tank.
(I understand all the stuff about the BIO cleaning all the crap from the fuel system) I did this once before with 20% for 2 tanks but didn't continue because at that time the BIO was MORE than regular Diesel and I had to go way out of my way to get it-now the B99 is 40cents less than regular diesel here and I don't have to worry about any extra lubrication additive.
Comments, Thoughts?? Thanks!!

 

Welcome to the bio forum! Well made (ASTM) commercial bio should be fine for up to 6 months. The biggest threat to biodiesel is air. Keeping tanks as full as possible and keeping the bio to air interface as small as possible will allow it to last just fine with your warm temps.

I have 1lt jars of bio I made 6 years ago that are full to the cork with no air, on my lab shelves, and they are just a good as when I made them.

 

Thanks for the warm welcome!! I appreciate it!! I've been a member of the FTE for almost 15 years now, first active in the '73-'79 forum, then the '87-'96, then to the '99-'03 PSD forum-(I have a LATE '99 F350 XLT CC Dually 7.3 now) and am trying to learn more about Bio fuels........my truck has been meticulously maintained by the first owner and myself-has just 112k miles on it now, trying to fuel it cheaper and stop the hasstle of having to add an extra lubrication additive at the same time.
I am told by the fuel supplier (Glover Oil) in Melbourne, Florida that at current the Bio-Diesel is made from beef tallow from out west-they used to have soy bean stuff about 3 years ago......am I safe with a CLEAN fuel system to start with in going to Bio gradually and ending up with B99 on my 6th tank from now? do the 7.3s like 99% BIO?

 

5 years ago I did the same thing by gradually going up in concentration over the course of several tanks until I filled it with B100 within a couple months, and had no problems with any sort of filter plugging with built-up deposits. I had also checked the fuel filter twice to find nothing. So I presume I had a clean tank and fuel system to begin with. I am just over 150K miles with 30K of those miles on B70 and up. Just a couple months ago, I dropped my tank to do the hutch and harpoon mods, and was amazed at how spotless it was in there. Even the mixing screens were immaculate, with no junk on them whatsoever. So as far all as those warnings about filter plugging when running biodiesel, it all depends on the condition of you fuel system to start with.

I think 7.3 PSD's run outstandingly well on biodiesel. All of my Blackstone OA's come back great with no indication of any sort of oil dilution. My latest emissions test outperformed the test results of my 1995 Mercedes E300D in the opacity reading. My 7.3 got an 8% opacity, while the Mercedes got 15%. To me this means more complete combustion.

 

Great info guys!! Thanks very much!

 

fabmandelux is correct. The standard is ASTM 6751 and the property you refer to about "fuel going bad" is oxidative stability. The ASTM test method for oxstab is EN15751. Oxstab depends on many things including the process used to esterify the biodiesel as well as the raw material used to begin with (tallow, waste vegetable oil, poultry oil, or virgin plant oils. Simply speaking, it is a measure of haw fast it will become rancid like the bacon grease you leave in the skillet too long. Properly treated raw oil that is properly processed will give you no problems.

 

Got a tank of B99 yesterday, have driven 35 miles so far, all seems good so far....20cents cheaper than dino and no having to add extra lubrication additives!!