How to Replace an In-Tank Fuel Pump in a 1993 Chevy Cheyenne Pickup Truck

Several large gas cans are needed to do this job.

The hardest part of replacing a fuel pump on a 1993 Chevy Cheyenne pickup is removing the gasoline from the tank. In addition to needing containers to hold 20 gallons of fuel--if the tank is nearly full--a pump is also needed to transfer the gas from the tank to the containers. All this is avoided if the tank is close to being empty, but because General Motors does not provide ease-of-access to the pump or install a drain plug on the tank, this job can be challenging.

Things You'll Need

• Fuel container
• Transfer pump
• Jack
• Jack stands
• 3/8-inch socket set
• Screwdriver set
• Shop hammer
• Punch

Instructions

1. Raise the hood of the Cheyenne and disconnect the negative battery cable. This will prevent any possible sparks from igniting gasoline vapors. Pump the gasoline into suitable containers. Open the gas cap and insert a transfer pump hose into the tank and pump the gas into gas cans. The tank will be far too heavy to lower from under the truck if it is full.

2. Jack up the rear of the truck and install jack stands under the rear axles. Lower the truck and make sure the vehicle is secure. Follow the filler tube from the tank fill area to the gas tank. The clamp holding the hose to the tank is easier to access once the tank is lowered. Place a jack under the tank and lower the tank by loosening the retaining bolts holding the tank straps in place.

3. Loosen the clamp that secures the filler tube and remove the tube. Lower the tank completely and remove the fuel supply lines that are attached to the pump assembly. There are two connectors that supply electricity to the pump--the main connector and the in-tank connector. Unplug the main electrical connector and use a punch and hammer to unlock the retainer ring that secures the pump assembly into the tank.

4. Unplug the old pump in-tank connector and unscrew the hose clamps that attach the pump discharge to the discharge tube. Pry off the lower filter/strainer that is fixed to the bottom of the pump. Lever the lower pump-holder bracket slightly downward, then pull the bottom of the pump out and down to release it from the rubber hose.

5. Install the new pump by pushing the top into the rubber hose connector and fitting it into the bottom seat. Make sure the rubber isolator is in place. Tighten the upper hose clamp and install a new filter/strainer. Plug the pump into the in-tank connector and install a new rubber gasket onto the tank.

6. Place the pump assembly into the tank and use a hammer and punch to seat the retainer ring back into place. Attach the two fuel lines and plug the electrical connector back into the main wiring harness. Jack the tank up until the filler tube can be refitted. Install the fuel filler hose and tighten the clamp.

7. Jack the tank fully into place and tighten the straps that hold it into place. Lower the truck and refill the fuel tank. Install the negative battery cable and start the truck. Allow it to run and inspect the tank for fuel leaks.

References

• "Truck and Van Repair Manual", Chiltons: 1993
• AA1 Car: Troubleshoot Fuel Pump