MC0400311-121 Cessna Improved Fuel Vent Line LH-Ext | MC0400311121

Please confirm the MC0400311-121 left hand fuel vent line’s compatibility with your aircraft’s extended range tank using these documents:

• Fuel system parts section of McFarlane Aviation catalog (PDF)
• McFarlane Aviation continued airworthiness instructions for installation of replacement fuel vent lines
• McFarlane Aviation fuel vent line installation tips (PDF)

Note for 150, 150A aircraft models: Only eligible for use with the upgraded Cessna vent assembly 0523552-2. These aircraft originally used 1/4″ vent lines, however they may be upgraded to a 3/8″ vent line with the installation of the P/N 0523552-2 vent assembly per the applicable IPC.

Note: The check valve is not included with the fuel vent line.

The fuel vent line on most Cessna single engine aircraft attaches to a check valve inside the tank to prevent fuel from flowing out of the vent line, but this valve has a weep hole that allows some fuel to pass to prevent pressurization of the fuel tanks. Unfortunately, this weep hole is much lower than the fuel level of a full tank. Fuel will continuously leak out of the vent line until the fuel level is below the weep hole. With the original vent line, you cannot fill the tanks without wasting a lot of fuel.

The Cessna heritage aircraft also have a tank interconnect vent line that allows fuel from both tanks to leak out of the vent. When parked on an unlevel surface, the fuel loss from these aircraft may be many gallons.

McFarlane has solved this problem with a redesigned vent line featuring a unique hump that rises above the top of the tank. Some fuel can still escape through the weep hole and out the vent to prevent pressurization of the fuel tanks. However, fuel will stop leaking once the pressure is relieved, and the tanks will remain full.

Product Details:

• Manufactured by McFarlane Aviation, Inc.
• FAA-PMA direct replacement, no STC or 337 form needed
• Supersedes: 0400311-121, 0400311-33, 0400311-53, 0400311-87
• Included in kit MC0400311-121K
• Pays for itself by extending useful range and allowing you to fly with full tanks
• Stops environmental and asphalt damage