Replacing The Fuel Pump In Your Classic 1971 Vw Bug

If your 1971 VW Bug won't start, you may need to replace the fuel pump. Before doing so, you should check that fuel is getting to the carburetor and that the pump is bolted tightly to the engine. If you determine that the fuel pump needs to be replaced, you can follow the steps outlined in the Fuel Pump Replacement Procedure. This procedure includes important safety precautions to follow when working with the fuel system, such as disconnecting the cable from the negative terminal of the battery and ensuring that you do not mix up the ports on the fuel pump when reconnecting the fuel lines. It is also recommended to test the new fuel pump before starting the engine and checking for leaks.

Disconnect the fuel line at the pump

Disconnecting the fuel line at the pump is a crucial step in replacing a 1971 VW Bug fuel pump. Here is a detailed guide on how to do this:

Firstly, locate the fuel line. The fuel line runs from the front-mounted fuel tank, through the fuel pump, and into the carburetor. The fuel pump is located in the engine compartment.

Once you have located the fuel line, you will need to disconnect it from the pump. This process can vary depending on the model of your VW Bug. For example, for 1965 and earlier models, you will need to use a line wrench to unscrew the inlet line. Newer models may have a different process, so it is important to refer to your specific model's instructions.

When disconnecting the fuel line, be extremely cautious as gasoline is highly flammable. Take all necessary precautions, including working in a well-ventilated area, avoiding open flames or sparks, and wearing appropriate safety gear such as safety goggles and gloves.

After disconnecting the fuel line, you will need to deal with the remaining fuel in the line. Have a suitable container ready to catch any fuel that may spill. You can also refer to your VW Bug manual for instructions on how to properly drain the fuel line before disconnecting it.

Once the fuel line is disconnected, set it aside and remember the port it was connected to. The fuel pump has two ports: one for the incoming fuel line from the fuel tank and one for the outgoing fuel line to the carburetor. It is crucial to reconnect the lines to the correct ports during reassembly, or the pump will not work properly.

Now that the fuel line is disconnected, you can proceed to the next steps of replacing the fuel pump. Remember to refer to a qualified mechanic or a detailed repair guide for further instructions on replacing the fuel pump in your 1971 VW Bug.

Check for fuel flow

To check for fuel flow in your 1971 VW Bug, you can perform the following steps:

Firstly, make sure that your fuel tank is more than half full. Disconnect the fuel line at the pump, which comes from the fuel tank around the left side of the engine. If your tank is more than half full, the fuel should run out of this line by gravity. If it doesn't, try blowing into the line; if clear, you should hear bubbling in the tank.

If you are still unable to get a good stream of fuel from the tank, check for fuel filters in the engine bay, over the gearbox where the fuel line comes out of the body, or under the fuel tank up front. Replace any filters you find as they are cheap and easy to replace.

Once you have confirmed a good stream of fuel from the tank, you can test the fuel pump itself. Ensure that the pump is bolted tightly to the engine. Some older pumps have a small filter under a brass bolt on the side of the pump, close to the fan belt. If so, remove the bolt and clean the plastic filter underneath.

Next, replace the top on the fuel pump, set the parking brake, and put the transmission in neutral. Pull off the hose that runs from the fuel pump to the carburetor at the carburetor end. Put a 19mm box-end wrench (ring spanner) on the alternator/generator nut and turn the engine over. You should now get fuel being pumped out of the hose by the fuel pump.

If you have fuel at the pump but the pump is still not functioning, you likely have a defective fuel pump and will need to replace it.

It is important to note that gasoline is extremely flammable, so take extra precautions when working on any part of the fuel system. Always wear safety glasses and have a fire extinguisher on hand. Do not smoke or allow open flames or bare light bulbs near the work area. If you spill any fuel on your skin, rinse it off immediately with soap and water.

Test the fuel pump

To test the fuel pump of a 1971 VW Bug, you must first ensure that fuel is reaching the fuel pump. You can do this by disconnecting the line from the fuel tank to the fuel pump and checking if gas flows out. If there is no fuel flow, the fuel filter or fuel line may be plugged.

Once you have confirmed that fuel is reaching the pump, you can proceed to test the pump itself. Make sure that the pump is bolted tightly to the engine and check for any small filters under brass bolts on the side of the pump. If present, remove the bolt and clean the filter.

Next, replace the top on the fuel pump, set the parking brake, and put the transmission in neutral. Disconnect the hose that runs from the fuel pump to the carburetor at the carburetor end. Put a 19mm box end wrench on the alternator/generator nut and turn the engine over in the normal direction (clockwise). You should observe fuel being pumped out of the hose by the fuel pump. Repeat this process to ensure consistency.

If you observe fuel at the pump but the pump is still not functioning, the pump is likely defective and will need to be replaced.

Remove the fuel pump

To remove the fuel pump from your 1971 VW Bug, you'll need to follow these steps:

Firstly, ensure you take the necessary safety precautions as gasoline is extremely flammable. Work in a well-ventilated area, avoid open flames or sparks, and wear safety gear such as safety goggles and gloves.

Now, let's begin:

• Disconnect the cable from the negative terminal of the battery to prevent any accidental electrical discharge.
• Loosen the hose clamps and remove the two hoses (the incoming and outgoing fuel lines) from the fuel pump. On 1965 models and earlier, you'll need to use a line wrench to unscrew the inlet line.
• Remove the two nuts (13mm) that secure the pump to the engine. The rear nut can be a bit tricky to access, and you may need to remove the distributor cap to reach it.
• Carefully lift the fuel pump out of the engine compartment. Be gentle, as the intermediate flange is made of bakelite and can break if handled roughly.
• Once the pump is out, inspect the pushrod for any signs of wear or damage. Roll it on a flat surface to check for any bending. If it's in good condition, set it aside for reuse.
• At this point, you can take the old fuel pump to an auto parts store to see if they can provide a rebuilt or refurbished unit. If not, you can purchase a new one.

Remember to work safely and carefully throughout the process, and always be cautious when handling fuel system components.

Install the new fuel pump

To install the new fuel pump, you will need to follow these steps:

Firstly, apply a sealer to the engine case around the fuel pump hole. Then, place the lower gasket on top of the sealer. Next, take the bakelite insulator block and apply sealer to its underside before installing it, along with the pushrod guide tube, into the fuel pump hole. Ensure that the pushrod slides up and down easily in the insulator block.

After that, apply a thin coat of sealant to the bottom of the top gasket and place it into position, followed by applying more sealant around its edges. Check the proper operation of the pushrod by rotating the engine until the fuel pump pushrod reaches its lowest and highest points. Measure the pushrod to ensure it is between 4 and 5mm above the gasket on the flange.

Next, fill the lower chamber of the new fuel pump with universal grease. Set the fuel pump in place over the studs, gasket, and insulating block. Tighten it to the case with two 13mm nuts, torquing them to 18 ft-lb.

Finally, reconnect the fuel lines, ensuring that the top port on the fuel pump is the inlet from the fuel tank and the bottom port is the outlet to the carburetor. Tighten the hose clamps securely. Reattach the cable to the negative terminal of the battery. Start the engine and check for any leaks.

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