I need to drain my 01 diesel pick up fuel tank, and fix the fuel line, about 20 gallons of diesel. Parked beside my diesel pick up is my 03 gas powered motorhome, and its gas tank is sitting close to empty. I'm thinking about transferring the diesel from my diesel pick up to gas motorhome. After fixing the diesel fuel line, I'll transfer diesel back. I'm sure there will be some residual diesel left in the gas motorhome that will make its way thru the gas fuel system. I'll add 5 gallon of gas then fill up to dilute any diesel left. If the gas motorhome runs rough, I'll drain out of valve on fuel line and add gas. Until its running smooth and nothing but gas makes it thru the gas line. And maybe do a gas filter change. What do you think? Will it work or not?

It'll work but it would be easier and less messy to borrow a few gas cans from some friends.Bill

Around here, we call that, "Going to Duluth by way of Mankato".There is no good reason to contaminate the gas system with diesel fuel, despite the proximity. I'm assuming one or both vehicles move. A better solution would be to use a clean container and transfer in and out of that. Four six gallon fuel cans come to mind as does one of those 30 gallon sewer totes, especially if you have a fuel pump to aid in transfer.

Gas tanks don't have drain plugs and even those that do, will have good amount of fuel left on the flat bottom. Cans cost about $10 and you might find use of them in the future.When diesel engine will run with some percentage of gasoline in it, gasoline engine will simply die on diesel. Unpredictable engine dying on motorhome is not the thing I would look forward.

Buy or borrow gas cans. I think it's a bad idea to temporarily put diesel in a gasoline tank.Or just give the diesel away? It may be cheaper in the long run.

gbopp wrote:Buy or borrow gas cans. I think it's a bad idea to temporarily put diesel in a gasoline tank.Or just give the diesel away? It may be cheaper in the long run.X-2Not only that, the diesel will be contaminated with gasoline. That will be an expense repair to both vehicles.

Diesel temp storage in motorhome gas tank? | Good Sam Community

16 Replies

MEXICOWANDERER
Explorer
Sep 07, 2016
"Parked" way down the road are parts stores that will grin and smirk at the thought of a possible multiple O2 sensor sales extravaganza. Dual exhaust gas rigs sometimes have four of them. Tiny amounts of diesel contaminant raise hell with O2 sensors - but you can confirm this with a local emissions checking station.
dougrainer
Nomad
Sep 07, 2016
"I need to drain my 01 diesel pick up fuel tank, and fix the fuel line, about 20 gallons of diesel. Parked beside my diesel pick up is my 03 gas powered motorhome, and its gas tank is sitting close to empty".

You have 2 BAD things going here
1. Transferring Diesel to a GASOLINE TANK
2. LEAVING ANY GAS FUEL TANK EMPTY OR ALMOST EMPTY IS A RECIPE FOR DISASTER. There is always moisture in a fuel system . Leaving a Gas tank empty or almost empty will cause rust and corrosion on the Fuel pump system if IN the tank or Rust and corrosion on the Tank level sending unit. Then you will have rusty fuel clogging up the fuel filters or destroying the fuel pump if in the tank. Doug
path1
Explorer
Sep 06, 2016
Op here...

OK thanks folks. Guess I'll buy some buckets. No use pulling pick up bed. It's a sump drain at bottom of tank. Going to install couple shut off valves after re-routing the fuel line. A "mechanic" installed a new airdog system and the fuel line he put on, looks like a kid put it on. This was after the 11 year fass system broke.

Why can't stuff break close to home?

Thanks again
DrewE
Explorer II
Sep 06, 2016
If you happen to heat your home with an oil furnace, you could put the diesel fuel in the home heating oil tank. It's basically the same chemically as kerosene and similar (but not identical) to #2 fuel oil.

Going the other direction, filling your truck from the heating oil tank, should not be done, if only because the penalties for using non-road fuels to power vehicles driven on the public roads are usually very steep. The taxation on the fuels differs a lot, even if the products themselves are nearly identical.
Bobbo
Explorer II
Sep 06, 2016
Buy 4 of the 5 gallon diesel fuel cans. You can thank me later.
RDMueller
Explorer
Sep 06, 2016
I agree with rhagfo, remove the bed instead of dropping the tank. I did this a year ago on my 01 Ram diesel and it wasn't that difficult. If you have a few friends that can help, 4 people can easily carry the bed away after it is unbolted. There are ways to do it yourself as well. The bed can be jacked up high enough and then supported where you can drive/push the truck out from under the bed. Search YouTube, there are some good videos on doing this.

As far as I'm concerned, dropping the tank is only a good idea if you have a lift. If not and you're going to be crawling around under there, dropping the tank will be a PITA. Just my opinion!
Sam_Spade
Explorer
Sep 06, 2016
Kayteg1 wrote:

When diesel engine will run with some percentage of gasoline in it, gasoline engine will simply die on diesel.

It depends on the percentage but the amount of gas in the diesel had better be TINY.

And nothing wrong with a small amount of "oil" in your gas; some people do that on purpose. It's called "upper cylinder lube".

P.S. I too think your original idea is NOT GOOD. Gas cans are a much better solution.
K_Charles
Explorer
Sep 06, 2016
This is not a serious question.
rhagfo
Explorer III
Sep 06, 2016
There is always the option of removing the bed off the truck to access the top of the tank!
Muddydogs
Explorer
Sep 06, 2016
Why make life complicated, wouldn't 4 or 5 5 gallon buckets be easier and cheaper then putting diesel into a gas tank with the possibility of wasting a lot of gas trying to drain off the diesel residue? The cost of a fuel filter would pay for one bucket at least.