I just removed ~145 gal. of fuel out of the 165 gal. auxiliary fuel tank I am removing to free up bay space. Below is a photo I took of fresh diesel on the left and the old diesel on the right. The old stuff didn't have anything growing in it, but it looks terrible and smells a little rancid. When I bought the bus it had been sitting for 10yrs. The previous owner said that he always transferred fuel from the auxiliary tank into the main tank and would only fill the auxiliary. That meant the oldest fuel was always in the main tank. The bus ran from L.A. to Monterey, CA on the old stuff without any problem. Due to the transfer pump not working, the auxiliary tank's fuel didn't get used on the trip to VA. I have decided not to waste the fuel and I have been running it 50/50 with fresh diesel without any problems to date. I am carrying extra filters and am keeping an eye on the fuel pressure gauge. I did an unscientific test; I took two sticks, dipped one into the fresh fuel and one into the old. I lit them both in an attempt to see if there was a difference in the way they burned. I could not discern any difference between the two. At this point I have not added any additives. I welcome any comments or thoughts on this, especially if you all think it's not a good idea.
Is that the red diesel that I hear about? Isn't that stuff illegal to use in buses and if caught could be big fines?
Grant
I have some old kerosene lamps that the oil has turned dark, so it seems to be some kind of natural occurrence. I hope the fuel police could tell the difference. I know that the previous owner would drive to Mexico and buy fuel across the boarder. That is why he installed the auxiliary tank. I also know that he added fuel stabilizer to it but I think that stuff is only good for about a year, two at the most.
I think that if you carried a box of fuel filters with you and swapped them out every so often, you'd be alright. When I bought my bus, it had been sitting idle for about 6 or 7 years. I drove it home with no problem. Ran a couple of tanks of fuel (with some Marvel mystery oil).
That is not red diesel. The red diesel is darker in color.
So FWIW, I think you'll be ok.
Jimmy