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All Electric - Quarter-Filled Gas Tank

Discussion in 'Prime Fuel Economy & EV Range' started by dlegate, May 15, 2018.

  1. huskers

    huskers Senior Member

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    This car takes care of everything.
     
  2. sam spade 2

    sam spade 2 Senior Member

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    Just stating a simple fact.
    No need for name calling and over-reaction.
     
  3. schja01

    schja01 One of very few in Chicagoland

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    I've read (all) the manuals cover to cover several times and don't claim 100% recall.
    If I had a eidetic memory things might be different.
    I think instead of the curt RTFM response a snippet and page reference would be
    better.
    Just my 2 cents.
    J
     
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  4. sam spade 2

    sam spade 2 Senior Member

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    I don't own that model.

    And I think it is rude and presumptuous to expect someone else to spend their time doing something that you can do for yourself.
     
  5. schja01

    schja01 One of very few in Chicagoland

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    And here I thought this was an information sharing forum. Silly me.
     
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  6. srivenkat

    srivenkat Active Member

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    Isn't the gas tank a sealed/pressurised system, severely limiting the amount of moist air that can come and go? Also, per the below, Ethanol in the fuel can absorb any little water condensation and burn it off in the Engine? I am actually thinking E10 might be better than E0 in this regard. Also I saw somewhere online that the Ethanol in E10 replaces the carcinogenic MTBE that's in E0. Plus also that Ethanol keeps the injectors clean?

    Car Talk: Fuel tank condensation no longer an issue | News | ncnewsonline.com

    Also the summary last post in the below:

    gasoline - Should I really keep my gas tank at least half full? - Motor Vehicle Maintenance & Repair Stack Exchange
     
  7. sam spade 2

    sam spade 2 Senior Member

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    Mostly right. The "sealed" fuel tank is mostly sealed and greatly reduces the moisture infiltration......but does not eliminate it completely.

    MTBE has been outlawed in the US and isn't used in any motor fuel anymore.

    In most circumstances, there is NOTHING wrong with E-10.....but it does tend to deteriorate a bit faster than E0.

    The simple solution to this "problem" is to burn a tankful of gas every 3 months or so.
    Easy. Cheap. But it won't cure anybody's OCD.
     
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  8. srivenkat

    srivenkat Active Member

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    Thanks for your input. I wonder what E0 has instead of MTBE. Apparently Marina gas could still contain MTBE and shouldn't be mixed with E10 per the below:

    Where Are You Likely to Find MTBE? Beware of Mixing Ethanol-Free Gas

    Is it possible that regular gas stations could also be selling Marina gas (E0 with MTBE) with a label indicating so on the pump?
     
  9. sam spade 2

    sam spade 2 Senior Member

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    NO. Illegal.
    Unless maybe it is located very near to a marina and is labeled for "Off Road use only".
    Given the potential problems, I certainly hope not.

    The link you supplied is very good reading.

    Note that fuel systems for boats are generally not as sophisticated as they are for cars.......and gas with ethanol would tend to "load up" with water and eventually not run good. Without the ethanol, the water can easily be trapped in a simple sediment bulb.

    I am not aware the there really is any important difference in "marine gas" except for the absence of ethanol.
     
  10. Glenn G

    Glenn G Member

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    I think it's always a good idea to keep some fresh fuel in the tank, in MA it's much less expensive to fill up rather
    than charge, as of this writing.

    Regardless, I would burn off and replace the fuel in the tank at least several times per year, even if charging is less expensive, it's nickels and dimes compared to the consequences!
     
  11. fuzzy1

    fuzzy1 Senior Member

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    Here are two more relevant items. First, the fuel systems on PHEVs are far better sealed than on any other cars on the market:

    How designing the Chevy Volt's sealed gas tank brought automakers, CARB together | Autoblog

    and second, from your Prime's Owners Manual, page 104:

    upload_2020-9-1_15-8-19.png

    There is no need to be OCD about completely turning it over every few months.
     
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  12. sam spade 2

    sam spade 2 Senior Member

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    OMG. An Prius owner using solid facts and logic.
    How refreshing. :ROFLMAO:
     
  13. srivenkat

    srivenkat Active Member

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    In terms of a periodic burn-off, I see an easy to remember metric of 1-mile-a-day (recommended 5.3 gallons/6-months = ~0.5 gallons/month = 27 miles/month = ~ 1-mile/day). So, a trip or two totalling 6 miles/week (perhaps easy to remember if done every Monday or so) (Charge-mode will probably force the Engine to run hot-enough to expel any moisture generated?); this should keep the Engine lubricated as well and assure Engine-availability when really needed.
     
  14. route246

    route246 Member

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    I have 3200 miles in 3 months and 99% EV mode. I just started burning off the original petrol from the dealer when I took delivery, otherwise it would be on Full for the foreseeable future. Any fuel burn-off is going to be challenging and I have to remember to press hybrid mode every time I drive .

    I consider a Full tank an extra 80 lb. of payload (half an adult). Should I just add a few gallons when I get the low fuel warning light? Does the tank have a bladder which prevents an air pocket in the tank?

    What is a reasonable level to keep the tank at since I'm not using any fuel for my normal driving? 1/4 tank is more attractive because I can burn off the fuel and replace it every 3 months at a much quicker interval, too.
     
  15. srivenkat

    srivenkat Active Member

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    So, I started with this plan on Monday, forcing Charge Mode over a trip of 6 miles. Engine stayed on for the entire 6-miles due to Charge Mode and lower battery level (as opposed to simple HV mode which would have caused the engine to stop when not needed), so hopefully the engine got hot enough to expel any accumulated moisture and was exercised enough to lubricate all the parts. Will go with the Charge-Mode-for-six-miles every Monday and add 1 Gallon fresh gas every 2-months plan, while keeping the fuel level minimally at 1 or 2 bars.

    Note: I see I have a typo in my original calculation (should be 5.3 gallons/12-months instead of 5.3 gallons/6-months) but it doesn't change the 1-mile/day metric.
     
  16. schja01

    schja01 One of very few in Chicagoland

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    Charge mode does a number on your Eco Drive score. I’m getting 20 mpg.
     
  17. srivenkat

    srivenkat Active Member

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    Yes, although IIRC, it did add about 5 miles or so to the SoC in my test run, so it's not all that bad. Plus the intent here with Charge-mode is to burn-off some stale-to-be fuel while exercising/lubricating the engine to a hot enough temperature to expel any accumulated moisture in the system and replenish with some fresh fuel and overall increase high availability and longevity of ICE.
     
  18. schja01

    schja01 One of very few in Chicagoland

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    Agreed it’s a very effective method to burn off fuel.
     
  19. not_a_prius

    not_a_prius Junior Member

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    anyone was who says gas goes bad is an idiot

    I live in a DRY area never had old gas go bad (10% ethanol)( year old ethanol was fine for me never had an issue)
    what makes it go bad is water getting into the tank if water is getting into the tank you have a bad leak somewhere or you took the car for a swim (flooded out)
     
  20. fuzzy1

    fuzzy1 Senior Member

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    Count me in as one of those idiots. A year ago I tried to start a small gas farm engine that sat fueled in dry storage unused for two or three years. One of those little fuel tanks with a vented cap. No luck, just many wasted pulls of the starting rope. Re-checking the fuel, it appeared the color of urine of someone very dehydrated. After sucking the dark yellow fuel out (no water found) and replacing it with fresh and much more clear fuel, it started right up and ran just fine during a five minute test run.
     
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