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Fill up or not? [message #370783] Wed, 23 November 2022 12:12 Go to next message
boybach is currently offline  boybach   
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Last winter I filled the gas tanks (as much as I could) thinking it would be better than having the tanks partly empty. Logical or not?

Larry


Larry - Victoria BC - 1977 ex-Palm Beach "Ol' Leaky" 40,000 miles, PO said everything working but forgot the word NOT. Atwood helium fridge, water heater & furnace. SS exhaust system, Onan, Iota Converter, R134A, New fuel lines & heat exchange hoses
Re: Fill up or not? [message #370784 is a reply to message #370783] Wed, 23 November 2022 14:05 Go to previous messageGo to next message
Matt Colie is currently offline  Matt Colie   United States
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Larry,

First - I (imeo) believe you are correct.

There are two big parts of the considerations here.

First is water. It is in the air and all vented tanks "breathe". The breathing is comes from two sources.
First of these is changes in temperature. The expansion and contraction of the tank, fuel and all will cause air to move in and out. So, when warm air gets sucked into the cold tank, some of the humidity will condense. Then, even if no changes in temperature, the barometric pressure can help the tanks collect fresh wet air.

The second is that the tank breathing helps the lighter fractions of the fuel leave and stay gone. This gets really bad if you have filled the tanks with a winter blend fuel.

Matt


Matt & Mary Colie - Chaumière -'73 Glacier 23 - Members GMCMI, GMCGL, GMCES
Electronically Controlled Quiet Engine Cooling Fan with OE Rear Drum Brakes with Applied Control Arms
SE Michigan - Near DTW - Twixt A2 and Detroit
Re: Fill up or not? [message #370785 is a reply to message #370784] Wed, 23 November 2022 14:42 Go to previous messageGo to next message
mghamms is currently offline  mghamms   United States
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Fill

1977 Kingsley 455 as stock as it gets except lots of Ragusa parts
Re: Fill up or not? [message #370786 is a reply to message #370785] Wed, 23 November 2022 17:39 Go to previous messageGo to next message
boybach is currently offline  boybach   
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Filled this afternoon. Razz

Larry


Larry - Victoria BC - 1977 ex-Palm Beach "Ol' Leaky" 40,000 miles, PO said everything working but forgot the word NOT. Atwood helium fridge, water heater & furnace. SS exhaust system, Onan, Iota Converter, R134A, New fuel lines & heat exchange hoses
Re: Fill up or not? [message #370787 is a reply to message #370783] Wed, 23 November 2022 19:38 Go to previous messageGo to next message
lqqkatjon is currently offline  lqqkatjon   United States
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You absolutely want full tanks when stored.

With our metal tanks, empty tanks rust much easier. Full tanks rarely are rusted.

Dealing with stale gas is much easier then rusted tanks. But from my experience, 50 gallons of gas in our gmc 6 months later really is fine. Has worked for me for 10 years for my gmc. And for 20 years of storing my ski boat. Gmc sits 3-6 months between fall and spring. My ski boat sits from labor day to memorial day.


Jon Roche 75 palm beach EBL EFI, manny headers, Micro Level, rebuilt most of coach now. St. Cloud, MN http://lqqkatjon.blogspot.com/
Re: Fill up or not? [message #370788 is a reply to message #370783] Thu, 24 November 2022 09:17 Go to previous messageGo to next message
JohnL455 is currently offline  JohnL455   United States
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Location: Woodstock, IL
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I keep enough to run the gen if needed for emergency so about 1/3. I keep 1/8 or less in all other stored vehicles. But I store indoors and temp is stabile at 50°F. The evil E10 can support 1 tablespoon per gallon of water in solution and keep it from rusting/ collecting. That would be a lot of water to saturate over one season. E0 can not keep water in solution and water sits on the bottom, freezing and thawing.

John Lebetski
Woodstock, IL
77 Eleganza II
Re: Fill up or not? [message #370804 is a reply to message #370788] Thu, 01 December 2022 07:10 Go to previous messageGo to next message
tphipps is currently offline  tphipps   United States
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Consider adding Sta-Bil to your full tanks. I use it for my emergency gas that is in storage for the Hurricane season. Got to be prepared. Never had a problem.
Tom


2012 Phoenix Cruiser model 2552 KA4CSG
Re: Fill up or not? [message #370807 is a reply to message #370804] Thu, 01 December 2022 11:10 Go to previous messageGo to next message
boybach is currently offline  boybach   
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Fuel stabilizer sounds like a good idea, but my tanks are already full and AFAIK it should have been added before I filled up so it got well mixed in?

Larry


Larry - Victoria BC - 1977 ex-Palm Beach "Ol' Leaky" 40,000 miles, PO said everything working but forgot the word NOT. Atwood helium fridge, water heater & furnace. SS exhaust system, Onan, Iota Converter, R134A, New fuel lines & heat exchange hoses
Re: Fill up or not? [message #370811 is a reply to message #370807] Thu, 01 December 2022 15:54 Go to previous message
tphipps is currently offline  tphipps   United States
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Registered: August 2004
Location: Spanish Fort, AL
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Should mix somewhat as you add it. Drive the coach around the block and stir it up. Yes, Sta-Bil should be added first, but we are only human.

2012 Phoenix Cruiser model 2552 KA4CSG
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