Replacing The Fuel Pump On A D100: Step-By-Step Guide

The fuel pump in a John Deere D100 lawn tractor is mechanical, making it longer-lasting than an electric fuel pump. The pump is bolted to the engine block, and as the engine turns over, a rod presses into a diaphragm inside the pump, creating suction. The diaphragm is delicate and can tear easily, causing the machine to fail to start. To replace the fuel pump, park the lawnmower on a level surface, engage the parking brake, and turn the ignition key to the OFF position. Open the hood, locate the fuel pump, and turn the fuel valve to the OFF position. Use needle-nose pliers to slide the clamps on the fuel lines back, then slide the fuel lines off each end of the fuel pump. Finally, remove the bolts holding the fuel pump to the engine block and slide the pump off.

Locating the fuel pump

To locate the fuel pump on a John Deere lawn tractor, first, park the lawnmower on a level surface and engage the parking brake. Turn the ignition key to the "OFF" position.

Open the hood of the tractor and locate the fuel pump on the left side of the engine, below the engine shroud. The fuel pump is a mechanical pump bolted to the engine block. It will have fuel lines attached to both ends, controlled by clamps and a fuel valve.

Turning off the ignition and fuel valve

To turn off the ignition and fuel valve on your John Deere D100, follow these steps:

Park your lawnmower on level ground and engage the parking brake. This is an important safety measure to prevent accidental movement during the fuel pump replacement process. Once the mower is securely parked, turn the ignition key to the "OFF" position.

Now, open the hood of the tractor. Locate the fuel pump on the left side of the engine, below the engine shroud. You will see the fuel valve near the fuel pump. Turn this valve to the "OFF" position as well. This step ensures that the fuel supply is cut off before you start working on the fuel pump.

At this point, you have successfully turned off both the ignition and the fuel valve. You can now proceed to the next steps of replacing the fuel pump on your John Deere D100. Remember to exercise caution when working with fuel systems and refer to a qualified mechanic if you are unsure about any part of the process.

Sliding off the fuel lines

To slide off the fuel lines, you'll first need to park your lawnmower on a level surface and engage the parking brake. Turn the ignition key to the "OFF" position and open the hood of the tractor.

Locate the fuel pump on the left side of the engine, below the engine shroud. Turn the fuel valve to the "OFF" position. Now, use needle-nose pliers to slide the clamps on the fuel lines back. You should do this on each end of the fuel pump. Finally, slide the fuel line off each end of the fuel pump.

It's important to note that the diaphragm inside the fuel pump is delicate and can tear easily, so handle it with care.

Removing the bolts holding the pump

To remove the bolts holding the fuel pump of a John Deere lawn tractor, you will need needle-nose pliers and a tool that can be used to turn two 3/8-inch bolts. This process will take about 10 minutes.

First, park the lawnmower on a level surface and engage the parking brake. Turn the ignition key to the "OFF" position. Open the hood of the tractor and locate the fuel pump on the left side of the engine, below the engine shroud. Turn the fuel valve to the "OFF" position.

Now, slide the clamps on the fuel lines back, on each end of the fuel pump, with the needle-nose pliers. Then, slide the fuel line off each end of the fuel pump.

Finally, remove the two 3/8-inch bolts holding the fuel pump to the engine block, and slide the fuel pump off.

Replacing the pump and ensuring proper functionality

Firstly, park your John Deere D100 lawn tractor on a level surface and engage the parking brake. Ensure you have the necessary tools, including needle-nose pliers and a suitable wrench for the bolts.

Turn the ignition key to the "OFF" position and open the hood. Locate the fuel pump on the left side of the engine, usually below the engine shroud. Turn the fuel valve to the "OFF" position.

Before proceeding, it is important to note that the diaphragm inside the fuel pump is delicate and can tear easily. When handling the pump, avoid applying excessive force or twisting the unit, as this could damage the diaphragm.

Using your needle-nose pliers, slide back the clamps on the fuel lines at each end of the fuel pump. Then, carefully slide the fuel lines off each end of the pump.

Next, remove the bolts holding the fuel pump to the engine block. The size of these bolts may vary, but they are typically 3/8-inch. Once the bolts are removed, carefully slide the fuel pump off the engine block.

Now, you can install the new fuel pump. Start by sliding the fuel pump onto the engine block and securing it with the bolts you removed earlier. Ensure the pump is firmly in place but be careful not to overtighten the bolts.

Reattach the fuel lines to each end of the new fuel pump, ensuring a secure connection. Use your needle-nose pliers to slide the clamps back into place, securing the fuel lines to the pump.

Finally, turn the fuel valve to the "ON" position and check for any fuel leaks. If no leaks are detected, start the engine and let it run for a few minutes to ensure the new fuel pump is functioning properly.

If your new fuel pump was delivered without fuel in it, you may need to prime it before starting the engine. Refer to your pump's instructions for the correct procedure.

If you encounter any issues during the replacement process or if the tractor exhibits unusual behavior after the new pump is installed, consult a qualified mechanic or refer to a John Deere service manual for further guidance.

Frequently asked questions