Good idea to add fresh diesel to tank already about half full of five year old fuel???

[myrtlemaye]

We have a 300 gallon diesel tank that is still 1/3 to 1/2 full of five year old fuel. It has had stabilizer added to it a couple of times. Is it an OK idea to have the tank topped off with fresh fuel and more stabilizer or would it be a much better idea to try to pump the old fuel into a couple of metal 55 gallon drums and then completely fill the tank with fresh fuel. Opinions and experience would be much appreciated.

 

[Green Co.]

If it's had stabilizer added periodically, the only concern I would have would be algae in the tank. Old way of checking, not sure if it holds true with todays #2 fuel, if the fuel in the tank is still clear and green-ish colored, it's ok. But if the fuel is cloudy or brown-ish colored, you could have an algae problem.

Algae grows in the moisture accumulated in a partially filled tank. When the fuel is used, the algae can plug filters, always a good idea to have a good supply of fuel filters. There are additives for algae contamination, but I am unfamiliar with them, which ones work, etc.

 

[myrtlemaye]

Thank you Green Co. I think we will go ahead and fill the tank. We have kept stabilizer in it and have no problems with the fuel in the tractor. We will stabilize again when the new fuel is in. By filters do you mean the filter on the tank that filters the fuel as it is being dispensed?

Thanks again

 

[Green Co.]

MM, both the tank filter and the fuel filter on the tractor. The tractor filter being the most important in keeping contaminants from the injectors. But a good filter on the tank is just added insurance. I have one on mine (an orange see-thru from Tractor Supply) that works well. When it begins to get dirty, the fuel flow slows down.

Good Luck

 

[TheGatherer]

I use PRI-D in my stored diesel, it is at least 5 yo and no problems... I also have some gasoline that is more than 6 yo and with the PRI-G it runs the car fine, in my generator I mix 50-50 then no problem.

There's an additive sold at Wally World that will take care of algae 'Power Service' product name Diesel Klean the white bottle is what you want...

I use a good filter on my pump and change vehicle filter often to keep the injectors clean...