My MH 2015 Ford E450 has been sitting in my driveway since November 2019. I put Stabil in then, took it for a few short drives around 20 miles each and started it occasionally for a few minutes. Otherwise, it's just been sitting. I have run the generator religiously every month for about 30 minutes with either the AC or heat pump on to exercise it. It starts right up and runs smooth. What can I do about the old gas as I still have another month or two before we take it out for a trip. I will be changing the oil in the next few weeks prior to the trip. Tank is still full and no room to add premium gas. Guess it's impossible to siphon the gas out. I don't want to run the generator for days to use some of it up. Any suggestions? Should I just forget it and go on the trip refilling it when needed?

I would. I personally have lost confidence with sta-bil. I would buy some seafoam. , fill tank with regular grade and take off.Why premium gas? Unless your vehicle needs the octane rating it's not necessary. Keep exercising that generator to get some fuel additives circulating. I wouldn't overthink this too much.

I'd just go on the trip and refill when needed. It might be a decent idea to let it run down fairly low before the first fill-up, though I doubt it makes a lot of difference in the long run.

Take it for one of your 20 mile trips and feel how it runs. While you’re on the road run the generator. The idea of putting some Seafoam or similar product is a good one.

I would siphon it out and post it for free. Know anyone that can let you borrow gas cans? Good news is it sounds like the genny uses the same tank. At least everything is still running. Gas degrades so buying 91 for engines that sit for long periods is a great idea. Like mentioned above if you do end up running the old gas try to use it all up before adding fresh. Assuming both engines are still running strong.

That's what I do, seafoam and run it, 2x a year. I last filled my 55g tank on 1.1.21 and still running on it and its only down a 1/2 on the gauge. I use the StarTron or Marine Sta-bil to slow down the ethanol separation. I make it a point to run my rv every week or two for a 50 or 60 mi round trip to a place where we can park and have a view while heating up a pre-cooked meal. In the future if possible, run it on longer trips to accumulate more miles in a shorter timeframe. Replenish your fuel more often, like every 4 monnths-6 mos. That way you are always ready to escape ! :)I buy my long term storage gasoline from stations near marinas where the hi-test is sometimes ethanol free for longer shelf-life. The pump is always posted and you can google search station locations near you.

What to do about old gas in tank | Good Sam Community

jjrbus
Explorer
Apr 05, 2021
klutchdust wrote:
jjrbus wrote:
klutchdust wrote:
jjrbus wrote:
I keep seeing stabil mentioned. Doing my due diligence, Star tron is a better product allowing fuel to last up to 2 years vs 1 year for stabil.

Sea Foam is just very expensive naptha. Stabil is very expensive naptha, with secret ingredient. Red dye? Star tron I have not deciphered yet.

I have switched over to Star tron because Stabil has failed miserably in my small yard and machinery engines. Sea Foam worked well in my MB 300D.

Looks like Star Tron is also very expensive naptha according to the MSDS. https://chemoventory.tcc.fl.edu/chemoventory/msds/_STARTRON_476.pdf

Maybe the 5% proprietary addition is the magic....:E

Possibly, after due diligence I do not use additives. Now If I got something out of a garage that had not run in a few years I might. Modern fuel has enough additives to suit me.
klutchdust
Explorer II
Apr 03, 2021
jjrbus wrote:
klutchdust wrote:
jjrbus wrote:
I keep seeing stabil mentioned. Doing my due diligence, Star tron is a better product allowing fuel to last up to 2 years vs 1 year for stabil.

Sea Foam is just very expensive naptha. Stabil is very expensive naptha, with secret ingredient. Red dye? Star tron I have not deciphered yet.

I have switched over to Star tron because Stabil has failed miserably in my small yard and machinery engines. Sea Foam worked well in my MB 300D.

Looks like Star Tron is also very expensive naptha according to the MSDS. https://chemoventory.tcc.fl.edu/chemoventory/msds/_STARTRON_476.pdf

Maybe the 5% proprietary addition is the magic....:E
jjrbus
Explorer
Apr 03, 2021
klutchdust wrote:
jjrbus wrote:
I keep seeing stabil mentioned. Doing my due diligence, Star tron is a better product allowing fuel to last up to 2 years vs 1 year for stabil.

Sea Foam is just very expensive naptha. Stabil is very expensive naptha, with secret ingredient. Red dye? Star tron I have not deciphered yet.

I have switched over to Star tron because Stabil has failed miserably in my small yard and machinery engines. Sea Foam worked well in my MB 300D.

Looks like Star Tron is also very expensive naptha according to the MSDS. https://chemoventory.tcc.fl.edu/chemoventory/msds/_STARTRON_476.pdf
ron_dittmer
Explorer II
Apr 02, 2021
DAS26miles wrote:
Just got back from Yosemite. Old gas wasn't an issue. I did throw in a can of Seafoam before leaving. Actually got the best MPG ever at 9.2 for the trip home. It's usually 7.8-8.2 mpg. Probably stretches of construction with 55 mph and the Grapevine climb was a slow 40mph because of stalled trucks.
Good for you original poster!

That is the best thing to do. Just burn off the old gas as long as the engine is running okay. As I mentioned before, that is my practice and I have yet to use additives.
klutchdust
Explorer II
Apr 02, 2021
jjrbus wrote:
I keep seeing stabil mentioned. Doing my due diligence, Star tron is a better product allowing fuel to last up to 2 years vs 1 year for stabil.

Sea Foam is just very expensive naptha. Stabil is very expensive naptha, with secret ingredient. Red dye? Star tron I have not deciphered yet.

I have switched over to Star tron because Stabil has failed miserably in my small yard and machinery engines. Sea Foam worked well in my MB 300D.
jjrbus
Explorer
Apr 02, 2021
I keep seeing stabil mentioned. Doing my due diligence, Star tron is a better product allowing fuel to last up to 2 years vs 1 year for stabil.

Sea Foam is just very expensive naptha. Stabil is very expensive naptha, with secret ingredient. Red dye? Star tron I have not deciphered yet.
DAS26miles
Explorer II
Apr 02, 2021
Just got back from Yosemite. Old gas wasn't an issue. I did throw in a can of Seafoam before leaving. Actually got the best MPG ever at 9.2 for the trip home. It's usually 7.8-8.2 mpg. Probably stretches of construction with 55 mph and the Grapevine climb was a slow 40mph because of stalled trucks.
klutchdust
Explorer II
Mar 12, 2021
wintersun wrote:
I would add a double dose of fuel stabilizer and not worry about it if it is a gas tank. With diesel fuel I would have the tank drained and the diesel fuel recycled. With diesel there is the potential for mold in the fuel tank and if this clogs the fuel system it can result in an expensive repair job.

There are additives to add to diesel fuel. I use them but not for water issues. Fuel system lubrication has become an issue with the loss of sulphur content.
wintersun
Explorer II
Mar 11, 2021
I would add a double dose of fuel stabilizer and not worry about it if it is a gas tank. With diesel fuel I would have the tank drained and the diesel fuel recycled. With diesel there is the potential for mold in the fuel tank and if this clogs the fuel system it can result in an expensive repair job.
AJR
Explorer
Mar 11, 2021
OP, great idea. Especially since your generator has been loving the gas & starting.

I run the gas tank down every fall at bed time for the camper & fill the tank with non-ethanol gas. Then I run the generator for a good hour under load. Just like all the old gas powered tools I had in the past. All was well the following spring.

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