DIY: Replacing Your Mechanical Fuel Pump

DIY: Replacing Your Mechanical Fuel Pump

   What you will need:

  1. Ratchet wrench set with iversal joint
  2. Tubing or open-end wrenches
  3. Hose clamp pliers or screwdriver
  4. Bolt or wooden dowel to plug fuel line from fuel tank
  5. Gasket sealer

   Before you start:
Get all the tools you'll need and have everything you might need handy. Allow yourself enough time so you do not have to rush. Since there will be fuel and fuel vapors present, to not smoke or allow open flames or sparks in the work area.

It would be an excellent idea to have a fire extinguisher rated for gasoline fires handy as well.

   Okay, let's get to work.


  1. Disconnect the negative battery cable.

  2. Disconnect fuel tank hose at the fuel pump, and plug the hose with a bolt or wooden dowel to keep any fuel from flowing out wires. Check the hose and if it is frayed or cracked, replace it with new fuel line hose.

  3. Disconnect the outlet line to the carburetor. Use a wrench on the fuel pump fitting and another on the line nut.

  4. Remove the two attaching bolts and remove the old fuel pump. Clean off any old gasket material from the mounting surface of the engine.


  1. Apply a coat of gasket sealer on both sides of the new gasket. Put the attaching bolts through the new pump and slip the gasket over the bolts.

  2. Install the new pump on the engine. Make sure that the in the pump is against the eccentric inside the engine, or that the push rod is correctly installed in both the engine and the fuel pump. If the push rod slides out, you can pack it with some heavy grease to hold it in place while you install the pump.

  1. Attach the fuel outlet line that runs to the carburetor. If it's difficult to connect, remove the other end of the line from the carburetor. Connect the line to the fuel pump, and then reattach the other end to the carburetor. Use a wrench to hold the fuel pump fitting and tighten the line nut with another wrench.

  1. Attach the fuel inlet hose from the gas tank, and the vapor return hose (if the vehicle is equipped with one). Tighten all clamps.

  2. Reconnect the battery ground cable, start the vehicle and check for leaks.

   This is fairly straightforward job. The only thing you need to remember is that you are working with open fuel lines and you need to be very careful. This job should take you about one to two hours.

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