Draining diesel tank

[BadDog]

My 2150 has seen very little use in the last few years, and the fuel is far from fresh. Not that much in the tank, so I plan to flush and add new fuel. Question is, what is the best procedure to get all the old out, without excess work and subsequent bleeding. Obviously it's easy to siphon out most, but that will leave at least a 1/2 in the bottom. The tank could be pulled and dumped/rinsed, but that leaves the lines. Is there a good low point to drain from? I'm guessing the filter bowl at the driver's right knee, and a clean while in there. It's running on what's in there, so I expect that is sufficient.

 

[Tx Jim]

I wish I lived closer so I could pick up your drained diesel and burn it in my tractor. Why are you wanting to drain your fuel tank? Dino diesel doesn't go bad similar to gasoline. Contaminants such as water & dirt can be filtered out of diesel.

 

[300zx]

BadDog, my B2150 had a clogged fuel filter when I got it. So, I wanted to flush the lines and clean the tank. I drained the tank by removing the hose at the fuel filter. Then I removed the tank and dumped the remainder in a can I use for cleaning parts. It only had 4 bolts to remove and the electrical connection at the fuel level sender. There was about a half inch of sludge in the bottom, so I removed the fuel sender and shot a high pressure hot water washer into the sender hole and let it drain out of the fill nozzle. It cleaned it well, but I ended up with a pinhole leak in the bottom I had to fix with JB weld. So, all in all, I was glad I cleaned it before I ended up with major rust in the bottom of the tank! Water is heavier than diesel or gas and always ends up at the bottom of the tank and can't get out because the drain nozzle is about 1/2 inch above the bottom.

John in VA

 

[BadDog]

TxJim:
It might still burn, but from what I think I know, old diesel left in a tank does degrade over time, and according to PO, this has sat a long time with that fuel. He couldn't even remember the last time he put fuel in it. Then there is water, potential "bugs", and loss of more volatile components leading to harder starts. I'm no petroleum engineer, but that's what I think I know. And sure, bad stuff can be filtered out, but with only a few gallons max (more like 1 I think) in the tank, why bother with clogged filters when it's no big loss to flush the system? I generally change most all fluids when I get anything like this with questionable maintenance (and no records), so that's just a small part.

300ZX:
Thanks, that's exactly my point, and exactly the information/confirmation I was hoping for.

 

[bulldog_shotgun]

on my B2150 the two bolts on the bottom of the tank have cotter pins in them you have to pull out first before you can get the nuts off, but yes the tank comes off easily

 

[furbody]

on my B2150 the two bolts on the bottom of the tank have cotter pins in them you have to pull out first before you can get the nuts off, but yes the tank comes off easily

What did you use to get to the cotter pins on fuel tank

 

[D2Cat]

Furbody, the post you are responding to is 7 years old. A good chance he's not going to respond.

 

[furbody]

Furbody, the post you are responding to is 7 years old. A good chance he's not going to respond.

Thanks do you know how to remove pins I see no way other than cut them out then don’t know how I’ll ever get them back in

 

[Oil pan 4]

I found a stick, like with bark still on it in the bottom of my tractors fuel tank. Makes you wonder what the heck are people thinking.
+1 on the drain and flush.