NGV FUEL TANK SOLENOID VALVE (REPLACEMENT PROCEDURES)

SUBJECT: NATURAL GAS VEHICLE (NGV) FUEL TANK SOLENOID VALVE REPLACEMENT

MODEL and YEAR: 1992-93 C2 TRUCKS WITH DEDICATED NGV SYSTEM

The in-tank fuel solenoid valves are replaceable on the 1992-93 2500 Natural Gas Vehicle (NGV) trucks by performing the following:

1. Remove the shield from the fuel tank that needs the in-tank solenoid valve replaced.

2. Open the fitting of the shortest line at the four-way "tee" connector at the fill side of the lines leading into the fuel tanks. See C-K Models Service Manual Supplement (Covering Natural Gas Models), Page 4-7, Fuel Control Section, Fig. 4-6.

CAUTION:

The gas will escape under high pressure for a brief moment. Wear eye protection and keep face and skin away from the area of escaping gas.

The overflow feature of the in-tank solenoid will stop the flow of gas.

3. Disconnect the electrical connector and the fitting to the fill side of the in-tank solenoid valve to be removed.

4. Attach Kent Moore tool #J-3971 1 to the fill side of the in-tank solenoid valve and move the truck outdoors to vent the fuel.

CAUTION:

Ground the over-temperature/over-pressure relief valve at the rear of the tank to a known good earth ground. This will prevent the buildup of static electricity while releasing the tank pressure.

5. Turn the handle on the Kent-Moore tool #J-39711 counter-clockwise to drain the fuel from the tank.

NOTE: Ice may form on the valve and stop the flow; DO NOT attempt to melt the ice. Let it thaw naturally and the flow will continue.

6. When the tank is empty remove the outlet line from the in-tank solenoid valve.

7. Remove the valve by rotating it counter-clockwise to unscrew it from the tank.

8. Lightly grease the seal on the new valve (P/N 12540064) with petroleum jelly and install it into the tank. Tighten to 35 lbs. ft. (47.5 N.m).

9. Reinstall the electrical connector and the inlet and outlet lines to the valve.

10. Reinstall the shields on the fuel tank.

General Motors bulletins are intended for use by professional technicians, not a "do-it-yourselfer". They are written to inform those technicians of conditions that may occur on some vehicles, or to provide information that could assist in the proper service of a vehicle. Properly trained technicians have the equipment, tools, safety instructions and know-how to do a job properly and safely. If a condition is described, do not assume that the bulletin applies to your vehicle, or that your vehicle will have that condition. See a General Motors dealer servicing your brand of General Motors vehicle for information on whether your vehicle may benefit from the information.