Launch Slideshow

Do-it-yourself carburetor cleaning

Do-it-yourself carburetor cleaning

  • Fuel left inside an engine for longer than 30 days begins gumming up, forming a varnish-like material that clogs up the small jets and ports in the carburetor. To clean the bowl, use carb cleaner and scrape out the varnish.

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    Fuel left inside an engine for longer than 30 days begins gumming up, forming a varnish-like material that clogs up the small jets and ports in the carburetor. To clean the bowl, use carb cleaner and scrape out the varnish.

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    Subaru Industrial Power Equipment

    Fuel left inside an engine for longer than 30 days begins gumming up, forming a varnish-like material that clogs up the small jets and ports in the carburetor. To clean the bowl, use carb cleaner and scrape out the varnish.
  • When cleaning the carburetor, first drain the carburetor bowl by removing the drain screw.

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    When cleaning the carburetor, first drain the carburetor bowl by removing the drain screw.

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    Subaru Industrial Power Equipment

    When cleaning the carburetor, first drain the carburetor bowl by removing the drain screw.
  • Often its easier to completely remove the carburetor for cleaning. Start by removing the choke lever. Unlatch the governor link and the tensioning spring with needle nose pliers.

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    Often its easier to completely remove the carburetor for cleaning. Start by removing the choke lever. Unlatch the governor link and the tensioning spring with needle nose pliers.

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    Subaru Industrial Power Equipment

    Often it’s easier to completely remove the carburetor for cleaning. Start by removing the choke lever. Unlatch the governor link and the tensioning spring with needle nose pliers.
  • Check the gasket on the inside of the air filter assembly to be sure its in good shape.

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    Check the gasket on the inside of the air filter assembly to be sure its in good shape.

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    Subarua Industrial Power Equipment

    Check the gasket on the inside of the air filter assembly to be sure it’s in good shape.
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    Check the gasket on the inside of the air filter assembly to be sure it’s in good shape.

  • Remove the hinge pin from the float. With the float comes the needle, which should be cleaned.

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    Remove the hinge pin from the float. With the float comes the needle, which should be cleaned.

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    Subaru Indstrial Power Equipment

    Remove the hinge pin from the float. With the float comes the needle, which should be cleaned.
  • After lifting the float, the main jet in the carburetor is visible. The jets passage is where fuel flows through the carburetor into the combustion chambers. To inspect, remove the jet with a flat blade screwdriver.

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    After lifting the float, the main jet in the carburetor is visible. The jets passage is where fuel flows through the carburetor into the combustion chambers. To inspect, remove the jet with a flat blade screwdriver.

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    Subaru Industrial Power Equipment

    After lifting the float, the main jet in the carburetor is visible. The jet’s passage is where fuel flows through the carburetor into the combustion chambers. To inspect, remove the jet with a flat blade screwdriver.
  • To open the passage of the jet, spray carb cleaner on it and use one bristle of a wire brush to insert and clear out any particles or gummed fuel. Be careful not to make it any larger than its original size.

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    To open the passage of the jet, spray carb cleaner on it and use one bristle of a wire brush to insert and clear out any particles or gummed fuel. Be careful not to make it any larger than its original size.

    600

    Subaru Industrial Power Equipment

    To open the passage of the jet, spray carb cleaner on it and use one bristle of a wire brush to insert and clear out any particles or gummed fuel. Be careful not to make it any larger than its original size.
  • The limit cap is part of the tamper-proof system required by the EPA. It is a non-serviceable part, so handle it with extra care.

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    The limit cap is part of the tamper-proof system required by the EPA. It is a non-serviceable part, so handle it with extra care.

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    Subaru Industrial Power Equipment

    The limit cap is part of the tamper-proof system required by the EPA. It is a non-serviceable part, so handle it with extra care.
  • Clean the main nozzle passage until its free of grime. Be sure the holes on the sides are open and clean as well.

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    Clean the main nozzle passage until its free of grime. Be sure the holes on the sides are open and clean as well.

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    Subaru Industrial Power Equipment

    Clean the main nozzle passage until it’s free of grime. Be sure the holes on the sides are open and clean as well.
  • Check to see the gasket (either flat or O-ring) that seals the carburetor bowl to the carburetor body is in position and not torn or warped.

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    Check to see the gasket (either flat or O-ring) that seals the carburetor bowl to the carburetor body is in position and not torn or warped.

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    Subaru Industrial Power Equipment

    Check to see the gasket (either flat or O-ring) that seals the carburetor bowl to the carburetor body is in position and not torn or warped.

Engine hunting and surging. Poor or no starting. Running solely on choke. These symptoms often point to the carburetor. When a carburetor is clean and working correctly, the engine should start easily, idle smoothly, accelerate without stumbling, and run with normal fuel economy.

Carburetors can be expensive to replace. But this important part often requires TLC rather than an entire replacement. With a few tools, a shop towel, and a couple of hours, you can clean the carburetor yourself and save time and money.

Treated fuels

The number of problems with carburetors has increased with the introduction of treated fuels such as E10, which contains ethanol. Ethanol, which is pure alcohol, attracts moisture and leads to corrosion inside the fuel tank and carburetor. Also, if E10 is left inside a small engine for too long, the volatile ingredients will eventually evaporate, leaving a thick, sticky, varnish-like product. This gummy varnish then lines the carburetor bowl and begins clogging up the small jets and ports, creating problems.

Even expired gas (sitting more than 30 days) poured in from a can might be dirty or contain rust that clogs lines. The solution is to drain old fuel from the float bowl and clean with carburetor cleaner.