How to Diagnose and Repair a Broken Lawnmower Fuel Line - Part 3

How to Diagnose and Repair a Broken Lawnmower Fuel Line – Part 3

This repair is continued from Part 2.

Tygon Fuel Lines

My local Gravely dealer said he’s seen a lot of deteriorated intake fuel lines and had just gotten this new fuel line kit, Mfg. Part #59207200 for about $30. The new fuel lines are Tygon® F-4040-A that are designed to resist swelling and hardening in gasoline and other fuels. Gravely is obviously is aware of the problem with the original fuel lines is offering this repair kit with everything you need – fittings, Tygon tubing and grommets.

Tygon Fuel Line Kit 59207200 - Gravely ZT1640 Lawn Mower

Here’s the new Tygon F-4040-A fuel lines compared to the original deteriorated and cracked fuel line:

Tygon® F-4040-A Fuel Lines vs Original Fuel Line

A closeup of the Tygon brand marking on the new fuel line.

Tygon® F-4040-A Fuel Tubing

New Fuel Line Installation Steps

Installing the new Tygon fuel lines is easy with only a tip to make the process easier.

Step 1:

Insert the fuel line into the tank, the end with the brass fitting and filter screen goes in first. Look inside the gas tank to see that the line is guided to the “deep” or “far end” of the tank and doesn’t coil up.

Installing the New Tygon Fuel Line - Gravely ZT1640 Lawn Mower

Step 2:

Slide the orange rubber grommet up the fuel tube until it almost meets the brass band as shown:

Adjust the Rubber Grommet

Step 3:

Press and seat the orange grommet into the fuel tank hole. Use only your fingers – do not use a screwdriver or other tools to avoid damaging the grommet.

Insert the Rubber Grommet into the Fuel Tank Sidewall

Step 4:

Push/press the fuel fitting into the grommet until seated as shown. Be extra careful to press straight in on the square head of the fitting. You risk breaking the 90 degree nipple if you press on it.

It took a bit of effort to press in the fitting, don’t be in a hurry. Consider wearing gloves if it digs into your palm.

Fuel Line Fitting Fully Seated in the Grommet

Step 5:

Push the black exterior fuel line onto the fuel fitting and secure with the wire hose clamp. Inspect the yellow Tygon fuel line inside the tank with a flashlight to verify it’s laying in the deep end of the gas tank.