Replacing Fuel Pump In Triumph 955I: Step-By-Step Guide

The Triumph 955i is a motorcycle engine manufactured by Triumph and used in several of their models, including the Daytona, Tiger, and Speed Triple. The fuel pump is located inside the fuel tank and can be accessed by removing the seats, battery, and some bolts and screws. When replacing the fuel pump, it is recommended to also replace the fuel filter and inspect the radiator cap and upper plumbing.

Some common issues with the fuel pump in the Triumph 955i include constant priming, short-circuiting, and failure to run. These issues can be caused by various factors such as a faulty ECU, wiring problems, or a bad relay. It is important to diagnose the specific cause of the problem before attempting to replace the fuel pump. In some cases, simply cleaning or tightening connections may resolve the issue.

When purchasing a replacement fuel pump, it is important to ensure compatibility with the specific Triumph model and year. Some aftermarket options are available, but it is crucial to verify the quality and compatibility of these parts before installation.

Overall, replacing the fuel pump in a Triumph 955i can be a complex task and may require specialized tools and knowledge of motorcycle maintenance. It is recommended to consult a professional or seek guidance from experienced individuals if one is unsure about the process.

Check for correct voltage at the pump plug leads

To check for the correct voltage at the pump plug leads of your Triumph 955i, you will need to use a multimeter. This is a device that measures electrical voltage, and you will need to set it to measure alternating current (AC) voltage, as pump motors are run on AC voltage.

Firstly, locate the pump plug leads. These will be the wires connected to the fuel pump. You will need to turn off the power to the pump before you begin.

Next, set your multimeter to the correct voltage range. Most fuel pumps run on either 120V or 230V, so set your multimeter to measure within this range. If you are unsure, it is best to set the multimeter to a higher voltage range to begin with, as measuring a higher voltage with a lower range setting can damage the multimeter.

Now, take the two probes attached to the multimeter and place one on each of the pump plug leads. It does not matter which probe is placed on which lead. Be extremely careful during this step, as these wires will have a high voltage running through them. Do not let the probes touch any other wires or components, and make sure they do not touch each other, as this could cause a short circuit.

Read the measurement on the multimeter. A good fuel pump should have a voltage reading of between 10% above or below the nameplate voltage. For example, if the nameplate voltage is 230V, a reading of between 207V and 253V is acceptable.

If the voltage reading is significantly different, there may be a problem with the fuel pump or the power supply. If the voltage is too low, there may be a problem with the power supply, such as a long or thin wire causing a voltage drop. If the voltage is too high, the fuel pump may be faulty and drawing too much power.

It is important to take safety precautions when working with electricity. Make sure you are wearing appropriate protective gear, such as rubber gloves and safety goggles, and be careful not to touch any live wires or components.

Check the fuel pump relay

To check the fuel pump relay on a Triumph 955i, you can perform the following tests:

• Check whether the relay coil is receiving 12V. If not, inspect the line and relay connector for any issues.
• Check whether the relay coil is grounded during the time the pump is supposed to be primed (at the turn of the key). You can do this by connecting a multimeter to both ends of the relay coil.
• Check whether the fuel pump relay is operating normally by listening for a clicking sound.
• Check for 12V at the relay contact on the fuse side. If there is no voltage, there may be a bad fuse, corroded fuse holder, bad line, or corroded relay socket.
• Check for 12V at the relay contact on the fuel pump side. If there is no voltage, the relay may be faulty.
• Check for 12V at the plug coils. If there is no voltage, the relay socket may be corroded, or there could be a bad line between the relay and the coils/pump.
• Check whether the pump is grounded correctly by connecting one multimeter pin to the pump ground and the other to the battery positive. If there is no ground, check the ground line for continuity.
• Check that the pump is receiving power. If it is not, there may be a bad line or a faulty pump connector.

It is important to perform these tests in the order listed and to fix any issues found before moving on to the next step.

Check the fuel pump is grounded correctly

To check that the fuel pump is grounded correctly, you will need to refer to your Triumph 955i manual to locate the fuel pump and its ground wire. The ground wire is usually black or brown and connects the fuel pump to the vehicle's chassis.

Once you have located the ground wire, you will need to check the ground connection for any signs of corrosion or looseness. If the connection is loose, tighten it securely. If there is corrosion, clean the connection using a wire brush or sandpaper.

You can also test the ground wire using a multimeter. To do this, connect one multimeter pin to the pump ground and the other to the battery positive terminal. If you do not get a reading, the ground wire is not connected properly, and you will need to check the wire for damage or corrosion and ensure a secure connection.

If the ground wire is damaged, you may need to add a dedicated ground wire directly from the fuel pump to a suitable grounding point on the vehicle's chassis. Ensure that any new ground wire is securely connected and properly insulated.

Check the fuel pump relay is operating normally

To check if the fuel pump relay is operating normally, you should follow these steps:

• Check whether the relay coil is powered (receiving 12V). If not, check the line and relay connector.
• Check whether the relay coil is grounded during the time the pump is supposed to be primed (at the turn of the key). You can do this by connecting your multimeter to both ends of the relay coil. If it is not grounded, there might be a corroded ECU pin or corroded relay socket.
• Check whether the fuel pump relay is operating normally (clicking). If not, the relay might be faulty.
• Check whether you get 12V at the relay contact on the fuse side. If not, you might have a bad fuse, a corroded fuse holder, a bad line, or a corroded relay socket.
• Check whether you get 12V at the relay contact on the fuel pump side. If not, the relay is faulty.
• Check whether the plug coils have 12V. If not, the relay socket might be corroded, or there may be a bad line between the relay and the coils/pump.

Check for a bad fuse or fuse holder

Checking for a bad fuse or fuse holder is a crucial step in diagnosing and resolving electrical issues in your Triumph 955i. Here are some detailed instructions to guide you through the process:

Step 1: Understand the Fuse Box

Before you begin, it's important to familiarize yourself with the fuse box of your Triumph 955i. Refer to the service manual or a diagram of the wiring system to identify the location of the fuse box and the specific fuses that need attention.

Step 2: Inspect the Fuse

Start by carefully examining the fuse in question. Look for any signs of damage, melting, or discoloration. A blown fuse will typically appear burnt or broken, indicating that it needs to be replaced.

Step 3: Check Voltage Readings

Use a multimeter to measure the voltage at the fuse terminals. With the ignition turned on, you should see voltage readings within the specified range for your Triumph 955i. If the voltage is outside this range, it could indicate a faulty fuse or a problem with the electrical circuit.

Step 4: Test the Fuse Holder

The fuse holder is the component that secures the fuse in place. To check for a bad fuse holder, carefully remove the fuse and inspect the holder for any signs of damage, corrosion, or melting. Ensure that the contacts within the holder are clean and free of debris.

Step 5: Check for Loose Connections

A loose connection at the fuse or fuse holder can lead to increased resistance and heat buildup, potentially causing the fuse to blow. Ensure that the fuse is securely seated in the holder and that all connections are tight and free of corrosion.

Step 6: Test with a Known Good Fuse

If the fuse appears intact and the voltage readings are normal, try replacing the fuse with a known good one of the same type and rating. This will help determine if the issue is with the fuse itself or another component in the circuit.

Step 7: Check Related Components

If you've identified a bad fuse or fuse holder, it's important to investigate related components in the electrical system. This includes checking the wiring harness for damage or corrosion, inspecting connectors for tightness and cleanliness, and verifying that all ground connections are secure and intact.

Step 8: Replace and Re-test

If you find a faulty fuse or fuse holder, replace it with a new one of the same type and rating. Once the replacement is made, re-test the electrical system to ensure that the issue has been resolved.

Remember to work with caution when dealing with electrical systems, and always refer to your Triumph 955i service manual or seek professional assistance if you're unsure about any procedures.

Frequently asked questions