Air in Gas Line?

Discussion in 'Outboard Maintenance' started by Rooster, May 3, 2015.

  1. Rooster

    Rooster Towee Calusa

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    I am running a one year old 20 HP 4 stroke. I am using non ethanol gas and disconnecting my fuel line after each use and running out of gas in the line. Lately my engine has been choking out and sometimes stopping soon after launching. I normally warm it up while parking my car so it's not like I am taking off cold... Bulb is pumped and full but it acts like it is not getting a good flow of gas. Could it be that there is a little air in the fuel line after re-connecting the line? Is there any way to avoid that? Is it really beneficial to disconnect after each use one only for long periods on non use? Will appreciate the Forum's thoughts on this!
     
  2. tomahawk

    tomahawk Well-Known Member

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    If you are using one of the newer ventless tanks, definitely disconnect from the motor. I learned that one the hard way. That tank expands and pushes fuel through the carb and into the crankcase.
     

  3. Rooster

    Rooster Towee Calusa

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    Thanks for the info! I should have stated that the motor is a Yamaha. My tank is a poly tank and it does have a twist vent on the cap - I have made sure it is open...
     
  4. CurtisWright

    CurtisWright Light, Strong, Cheap. Pick Two.

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    X2. Learned the hard way.
     
  5. CurtisWright

    CurtisWright Light, Strong, Cheap. Pick Two.

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    If it's carbureted it shouldn't be an issue as any air will flow straight through it into the intake of the engine.  I am Not sure how injectors handle it. 

    If it's an injected engine I wouldn't run it dry because there are bearings in the fuel pump that can rust when exposed to air.  In my 40 tohatsu TLDI  I run non ethanol and never run it dry for this reason.  In the off season from the end of February to mid may each year I fill the tank up with non ethanol,  put a fuel stabilizer in it and about 100:1 2 stroke oil and run it into the engine to keep fuel pump submerged and lubricated.  All this was based on advice from my certified Tohatsu dealer/mechanic.   Ive made it through two winters now without issue.