How to clean varnished gas from tank lines

Written by ashton daigle
  • Share
  • Tweet
  • Share
  • Email

When old gasoline is left in the fuel tank of your motorcycle, all-terrain vehicle or lawnmower it can cause a gunk-like varnish to form on the inside of your tank. This varnish can clog your fuel line and ultimately render your vehicle inoperable if it is not taken care of. There are a number of products you can use, ranging from acetone to special fuel-system cleaners, to remove varnish from your gas tank and line.

Skill level:
Moderately Easy

Things you need

  • Screwdriver
  • Wrench set
  • Medium size plastic container
  • Fuel-system cleaner or acetone
  • Drain pan
  • Rubber plug or duct tape

Show MoreHide


    Tank Line Cleaning

  1. 1

    Locate and remove the fuel line on your motorcycle, ATV or lawnmower. Exact locations will vary with different models. However, fuel lines generally run from your gas tank to your engine's carburettor. The fuel line can be removed by unscrewing the clamps that hold them in place with a screwdriver.

  2. 2

    Fill your plastic container about half way with fuel-system cleaner or acetone. Submerge your fuel line in the liquid for 3 hours.

  3. 3

    Remove fuel line from liquid. Dry the outside of the line with an ole rag. Allow the inside of the fuel line to dry out over night.

  4. 4

    Replace one end of the fuel line to your carburettor to the and the other end to your gas tank. Fasten the line in place by tightening the clamps with a screwdriver.

    Fuel Tank Cleaning

  1. 1

    Locate the fuel line and unscrew the clamp that holds it in place to your gas tank.

  2. 2

    Remove the gas tank from your motorcycle, lawnmower or ATV. Removal procedures will vary from model to model. Consult your owner's manual or parts house to determine the exact procedure for removing your specific fuel tank.

  3. 3

    Drain out your fuel tank of old gas if there is any in it. Empty the gas into a drain pan and dispose of it later.

  4. 4

    Insert the small rubber plug into the hole on your gas tank where the fuel line attaches. If you cannot find a rubber plug you can plug it with duct tape.

  5. 5

    Pour the contents of the fuel system cleaner into your gas tank and place your gas tank cover on. Hold your tank and shake it very well. Allow the cleaner to sit inside your tank for about 30 minutes.

  6. 6

    Empty the cleaner from your gas tank and allow your tank to dry out over night. Also remove the plug or duct tape from the gas line hole.

  7. 7

    Replace you gas tank by reversing the steps you used to remove it. Fill your tank with fresh gas, start your engine and allow it to run for about 10 minutes.

Tips and warnings

  • Because automobiles do not normally sit up for long periods of time, varnish in the gas tank or gas lines is not a common problem. However, if it does occur you can add a gas additive or fuel injector cleaner to your gas tank and this will normally handle the problem.

Don't Miss

  • All types
  • Articles
  • Slideshows
  • Videos
  • Most relevant
  • Most popular
  • Most recent

No articles available

No slideshows available

No videos available

By using the site, you consent to the use of cookies. For more information, please see our Cookie policy.