DEF in Fuel Tank

[grabinov]

Ok Gents,

I swear it wasn't me. A buddy with a 2016 2500 just accidentally put half a gallon of DEF in his fuel tank. He called me when he realized it. It's in his driveway and he hasn't started it. So:

DEF is 67pct water, so diesel fuel will float on top of it - his fuel tank is full (now full of fuel and DEF, LOL). That means that if he lets it sit overnight, the DEF will find its way to the bottom, presumably right where the fuel pickup is. What to do next.

One idea is to remove the inlet line from the under-bed fuel filter and then attach a hand pump to the line (like the bulb used on an outboard engine). Then "crank" the pump to suck fuel through the factory fuel pump n the tank until the DEF and some fuel are sucked out. Anyone know if this will work?

Next idea is to do the same but use the factory fuel pump to move the DEF and then fuel by cycling the fuel pump with the ignition just as you do after a fuel filter change. I don't see any reason this wouldn't work.

Go to dealer and let them do the same only they would cycle the pump on with a scan tool.

Go to dealer and have them drop the tank and drain everything out.

The tank doesn't have a drain plug I suppose? Not that I ever noticed. That would be as smart as putting one on a transmission pan. Why would they do something that smart at the factory when it costs an extra $1.50...

ideas?

 

[gsbrockman]

Drop the tank and do it right, preferably without any dealer intervention.

 

[Cummins12V98]

Kinda suks but I have to agree with the Gentleman above.

I slid my bed back n sucked 30 gallons of water and the rest fuel from my 98 12v. Hand dried out the tank changed filter and cracked injectors. Ended up with about a teaspoon in filter later when WIF came on.

So do it right.

 

[jhenderson]

Dropping the tank for a good cleaning is really the only way to be sure of no future problems. Just don’t start it for any reason. That would mean a complete fuel system cleaning for big $$$$.

 

[Wiredawg]

You can't go wrong removing the tank as a best practice, but if it were me, I would get one of those drill powered pumps a quarter inch hose and suck it down to the bottom of the tank. Check the tank emptiness by tapping the bottom of it. Next, use small hose clamps and attach a shop rag to sop any residual moisture out. Then get 5gal tanks and refill with fresh diesel to the top.

I believe this to be a safe fix, but won't dispute the best solution is tank removal and cleaning.

Cheers, Ron

 

[grabinov]

Thanks gents,

Is there a good way to drain the fuel before dropping the tank? I’d definitely rather do that than try to balance a tank full of fuel on a floor jack, but if i try to empty it with a hose won’t i end up with the hose stuck in the filler tube “flapper” doors at the top?

 

[BarryG]

Well a fuel nozzle will go in there and not get stuck so how about a piece of hard tubing x long then run the hose through it. drill type pumps work fairly well. Used one several times on my 01 to drain the tank down low when I had to drop it a few times over the years. I wouldn't want to try and balance 250 lbs of sloshing fuel on a jack at least a floor jack like I have used in the past. Or lift the bed and remove the pickup,fuel pump canister and remove from there.

 

[Wiredawg]

I replaced fuel sending unit on my 03 Ram 2500 4x4 using drill powered pump. You want to get all you can out. I used a transmission jack attachment on my floor jack. Use ratchet straps to secure tank to jack. Drop enough to remove hoses and connectors. Helps to jack truck up and set on jack stands. You may find instructions for draw straw product.

Go ahead and establish a cuss jar. On a bad day, I would prepay.

Cheers, Ron

 

[grabinov]

Thanks again. I'm looking at how to complete either option - drop tank or move the bed. I just watched a Titan Tanks install video on removing the tank and it looks easy if the tank is empty. And their video suggests a good way to drain it - remove the driver's side fender liner and pull the fill hose from the filler neck. Then pump from the hose, which is the size of a radiator hose, with no restrictions.

The video also makes it clear that even if you were to drain the tank with a pump, there would still be about a cup of fuel in the fuel pump intake cup. I'm not sure the DEF would have made it into that cup as it sunk through the diesel after dumping in the fill hose, but it could have!

Now I just need a spare place to store 30 gallons of fuel. Probably 6 5-gallon buckets...

 

[gsbrockman]

Store the 30 gallons of fuel on nearby weeds.

 

[Cummins2014]

Thanks again. I'm looking at how to complete either option - drop tank or move the bed. I just watched a Titan Tanks install video on removing the tank and it looks easy if the tank is empty. And their video suggests a good way to drain it - remove the driver's side fender liner and pull the fill hose from the filler neck. Then pump from the hose, which is the size of a radiator hose, with no restrictions.

The video also makes it clear that even if you were to drain the tank with a pump, there would still be about a cup of fuel in the fuel pump intake cup. I'm not sure the DEF would have made it into that cup as it sunk through the diesel after dumping in the fill hose, but it could have!

Now I just need a spare place to store 30 gallons of fuel. Probably 6 5-gallon buckets...

Although I don't have any advice as far as the best way to fix this problem. What I have read it takes very little of that DEF to mess things up . I would sure not want some of that stuff even evaporating in there with those crystals developing . That tank certainly needs to washed out thoroughly . Even water would flush all that DEF out, but then of course it would need to be dried out completely .

 

[mwilson]

Drain the tank and take it out. Clean tank and fuel pump module / sump bowl thoroughly.

We've had to completely replace 150 gallon fuel tanks because they can't be cleaned enough to be trustworthy after DEF contamination.

In his case he will be able to clean it where you can work through the fuel module hole.

It's the only safe way to save it. Are you absolutely certain that your friend has not so much as turned the key on???

Thousands of dollars at stake here if the whole truth has not been told......

 

[mwilson]

Do not take it to a dealer, they will have no choice but to document it......and he don't want that....

 

[Cummins12V98]

Are the new beds hard to slide back??? My 98 was not hard at all, the job was easy from the top. I had a 12V fuel pump I used to remove the water and fuel.

 

[EZeis]

He's sure he put def in the fuel tank? Sounds like he used a 2.5 gallon box jug since it happened in his driveway. How did he get the plastic flexible straw into the fuel neck past the flappers? I can't see that straw having the strength to push the flappers down. Flappers may even smash the straw. Takes a decent amount of force to push the flappers open with the fuel nozzle.

But if he did, I agree, remove tank. Definitely don't want to risk the fuel system by taking shortcuts.

Earl

 

[Cummins12V98]

He's sure he put def in the fuel tank? Sounds like he used a 2.5 gallon box jug since it happened in his driveway. How did he get the plastic flexible straw into the fuel neck past the flappers? I can't see that straw having the strength to push the flappers down. Flappers may even smash the straw. Takes a decent amount of force to push the flappers open with the fuel nozzle.

But if he did, I agree, remove tank. Definitely don't want to risk the fuel system by taking shortcuts.

Earl

Good points!

 

[grabinov]

You guys are awesome. Lol. I will verify honesty and accuracy. I’m pretty sure he’s being honest about not starting the truck at least (though maybe not accurate about where he put the DEF). He came home from work, filled up on the way home with fuel, parked in the driveway and then put in DEF so it would be ready for the next day. No reason he would have started it.

In my home state of California (sorry - it’s where my job is) they watch for environmental infractions using a combination of spy satellites, trained birds and nosy neighbors. Pretty sure I need to recover the fuel into buckets, but I’ll take Brockman’s advice about 99% of the time!

 

[MarkEagleUSA]

Not being a DEF user I admit I know next to nothing about it. But I'm wondering if a 1/2 gallon into a full tank (34 gal?) is really that bad? Seems it would be very diluted at that ratio...

 

[grabinov]

Not being a DEF user I admit I know next to nothing about it. But I'm wondering if a 1/2 gallon into a full tank (34 gal?) is really that bad? Seems it would be very diluted at that ratio...

That’s definitely the natural reaction, however, DEF is 67% water, so dumping it into diesel is like mixing oil and water - literally. They don’t mix. The diesel just sits on top, which means the DEF is the first thing ingested by the pump off the bottom of the tank, so your fuel system gets a half gallon dose of pure DEF. The engine won’t run on it so you have to push it all the way through the system and the fuel rails to get to clean diesel. By that time every part in the low and high pressure side has been contaminated.

With a very small amount of DEF, the system would separate it like it does with water. But I think a half gallon is asking a lot for the separators to catch.

 

[MarkEagleUSA]

That’s definitely the natural reaction, however...

Like I said, I know nothing about DEF but was curious about the "mix" in a full tank of fuel. Thanks for the expanation.