AN-6 Bulkhead Fitting

For GL1800

AN-6 Bulkhead Fitting that fits in the sending unit plate of a GL1800 can be created by modifying a tubing nut. Following these instructions will allow you to mount the fitting without having to trim the inside of your fuel tank.

Parts required are shown on the Pictorial Plumbing Schematic and listed on the Parts List Page.

In addition to the parts on the list you will need the following tools:

  • Bench Vise
  • Drill Motor
  • Center Punch & Hammer
  • 1/8", 1/2" & 9/16" Drill Bits or Step Bit
  • 9/16" x 18p Tap
  • 9/16" & 11/16" End Wrenches
  • Vise Grips

Remove the sending unit plate from your stock tank and clean it well. Honda's special tool and a 1/2" drive breaker bar make the job easy, but a hammer and punch will do.

Modify an AN-6 Tubing nut

The nut that comes with the bulkhead fitting will not fit without trimming your trim your fuel tank.

  1. Wrap the tubing nut with tape and put it in your vise. Drill out the tube end to 1/2". A step bit with a maximum size of 1/2" used from the threaded end will assure center.
  2. Thread the tube end of the Tubing with a 9/16" x 18p starter tap. Hand thread the tap into the threaded fitting end to make sure the new threads align.
  3. Your modified tubing nut should thread easily onto the Bulkhead fitting.

Prepare the Plate and Sealing Washers

See top view photo of the finished fitting installed on the sending unit plate for reference. Note how close to the white connector it is. This is the ONLY spot on the sending unit plate where the plumbing will fit!

  1. Mark a line 11.00mm from the outside edge on the bottom and top of the sending unit plate. This is the inside edge of the opening of your fuel tank and locking ring. N part of the bulkhead assembly can extend past this line.
  2. On top of the plate, mark the centerline of the bracket that holds the sending unit on the bottom side.
  3. Trim two edges, 45° to each other, off one Stat-O-Seal washer with your bench sander or file. Trim very close to the O-ring, but do not trim into the rubber and make sure to leave a bit of the capture area on the metal washer. Remove all burrs.
  4. Use the modified Stat-O-Seal washer to mark your drilling spot on the top of the plate. The seal should be tight against the white connector as shown. Center punch the plate.
  5. Refer to photos and check the Assembly Illustration for location and dimensions.
  6. Trim a straight side off the other Stat-O-Seal washer.
  7. Hold the straight trimmed edge of the Stat-O-Seal on the bottom of the plate against the sending unit bracket centered over the center-punch mark.
  8. Mark a trim line on the washer slightly inside the tank opening line.
  9. Trim the Stat-O-Seal washer on your line and check for clearance. With washer centered on your mark the edges must clear the tank opening line.

Drill Plate and Install Fitting

  1. After all clearances are verified drill a 9/16" hole in the plate on your center punch.
  2. If you are using step bits, you can start with a 1/2" step bit from the top and use a bigger bit from the bottom. The larger step bit will not clear the connector from the top.
  3. Remove all burrs and make sure the hole is clean and smooth.
  4. Put a small amount of ATV silicone on the top of the sending unit plate to fill any stampings.
  5. Put the drilled plate in a bench vise for a place to rest your wrench and ability to use both hands to finish assembly.
  6. Insert the bulkhead fitting through the Stat-O-Seal you modified for the top. Do NOT remove the seal after it's on the fitting or you risk pulling the O-ring out of the washer.
  7. Slip the modified Stat-O-Seal for the underside over the bulkhead fitting followed by one crush washer and the modified tubing nut.
  8. Make sure all the parts are inside the line draw to indicate the fuel tank opening.
  9. A pair of Vise Grips will help you hold the bottom seal in place while you tighten the tubing nut.
  10. Make sure the fitting is turned as shown to clear the locking ring tool.
  11. Hold the fitting in place while you tighten the nut. The nut must turn on the crush washer to keep from damaging the O-ring. You should not be able to turn the fitting by hand when tight.

You're done . . . set the assembly aside so the ATV silicone can dry while you work on the rest of the plumbing.

Please contact us if you experience any difficulty with installation or experience any problems with your kit.