When I bought my D6, it had sat outside, uncovered, by a creek for 6-8 years, with a full tank of fuel. That fuel burned just as well as any I've put in since.

If you're going to pump it and filter it, and maybe add some additive to it, that would be no problem. Add fresh fuel to it, and it would be good as new. If the tank was tight enough that it had built pressure (presumably from the atmosphere) then I would think that it was tight enough to keep out water. I saw a sign today for fuel @ $4.93..... I think I'd burn that stuff....

Rodney

This fuel tank pressure issue is starting to worry me.

It wasn't like a few lbs, it was more like 15 - 20 psi as I could push down on the cap as I opened it and it would pop back up with the play in the thread, also air was wistling through the threads before I popped the top off. As far as the difference in temp. goes it was last used in the end of September, early October when the temps are still in the 100 deg range, When I opened the tank on Friday it was like 75 - 80 deg.

I wouldn't worry about it as it is probably only the volitiles that had evaporated over time. Kind of like a Drum of Pennsylvania Light Crude Oil. Fill the drum and bung it up tight and set it in the sun, shake it aroound on the truck.

"CR" wrote:

This fuel tank pressure issue is starting to worry me.

It wasn't like a few lbs, it was more like 15 - 20 psi as I could push down on the cap as I opened it and it would pop back up with the play in the thread, also air was wistling through the threads before I popped the top off. As far as the difference in temp. goes it was last used in the end of September, early October when the temps are still in the 100 deg range, When I opened the tank on Friday it was like 75 - 80 deg.

I would consider that having pressure on the tank is a good sign, as it shows the cap and fittings were good and tight. It is easy to over estimate the pressure you feel, vs, what would show on a guage. Just like a 55 gallon drum that has set in the sun, when you take the bung out, but the fuel filler cap is close to 3 times the diameter, (2 inch bung = 3.1416 square inches surface area/ 6 inch cap = 28.27 sqare inches surface area). And if the tank was 1/2 full, you were venting 100 gallons of air (13.37 cubic feet of air (at 0 psi), I cannot remember Boyle's law to figure the volume if the air was compressed to X psi), out the threads holding the cap in place)

What you had was the vapor pressure of diesel oil at the prevailing temperature. If something pushed the pressure higher it would just condense some vapor and remain at the same pressure, IF--BIG IF, there's nothing in there but diesel oil!

Is there any reason to think it's anything but diesel? There's been no mechanical activity involving the tank, like pumping on it, has there? A four inch cap has an area of about 12.5 sq. in. A couple of PSI will lift 25 lbs. dead weight!

When we were kids, my brother and I came across an old abandoned oil well in PA. We unscrewed that 2 inch pipe plug off the oil line on the casing head. It shot out about 25 or 30 feet into the woods. We spent at least an hour looking for it. There was only 2 or 3 psi on it!

The fuel level in the tank can be seen in the filler screen, I would estimate it would take another 5 gallons to fill up the tank. The tractor only ran less than an hour after the lube truck filled it up on September 20, 2003. I called to our mechanic as I was waiting at the airport today and he said he thinks that it holds 375 gallons of fuel, he was baffeled to why the cap was under pressure all these years as he recalled having to fix the breathers on these before. Taking the cap off was like removing the pressurized radiator cap off a large radiator.

We are starting to wonder if it is really worth the chance, even though diesel is between $3.00 and $4.50 depending on order size and taxes, a new injector set is a few thousand dollars.

old diesel in the KINGDOM gets used in soaking down old cats. THE ROCKET has just been filled with a drum of diesel from this past winter. no one can remember anything about the drum. so why take a chance, use it to unseize a 1945 td-9. then toss the diesel in the wood stove next winter.
fuel maybe expensive, but filters, other problems and the headache is not worth it.

thansk
KoO
Published Author

I called our mechanic this morning, he said when he sends in the oil samples today he will see if they could run a test on the diesel.

Well we found out the diesel has bacteria growing in it, thanks for everyones input.

Actually the guy who does the tests on our oil said asked what kind of bio fuel concoction are we brewing because diesel is "fermenting". Who knows what got in there, as the fuel tank was flushed out when the transmission was worked on a year or two prior to being parked.