Replacing Suzuki Df250 Outboard Fuel Pump: Step-By-Step Guide

If you're looking to replace the fuel pump on your Suzuki DF250 outboard, there are a few things you'll need to do. Firstly, make sure you have the right replacement part. You can find fuel pumps designed specifically for the Suzuki DF250 on Amazon, with some offering advanced pressure relief valves and improved internals for better performance and durability.

Once you have the new fuel pump, you'll need to locate and disconnect the old one. This will involve relieving the fuel system pressure, draining the fuel from the vapor separator tank, and removing the intake manifold and flywheel cover. You may also need to disconnect various hoses and wiring connectors. It is recommended that you refer to a mechanic or a detailed guide for the specific steps and safety precautions.

After installing the new fuel pump, you'll need to reconnect all the relevant hoses and wiring, and ensure that the intake manifold and flywheel cover are securely in place. Finally, you can reconnect the battery cable and pressurize the fuel system, checking for any leaks.

Disconnect the fuel outlet hose from the VST and powerhead

To disconnect the fuel outlet hose from the VST and powerhead, follow these steps:

First, relieve the fuel system pressure and disconnect the battery cable for safety. Next, drain the fuel from the vapor separator tank into an approved container using the drain screw located at the tank's bottom and a drain hose. Then, remove the intake manifold by loosening and removing the mounting screws (usually 3, but some late-model 60/70 hp/1298cc powerheads have 4 bolts). Now, remove the vapor separator as an assembly from the back of the intake manifold. If the fuel outlet hose is still connected to the VST and powerhead, be sure to disconnect it before proceeding.

At this stage, you should have successfully disconnected the fuel outlet hose from the VST and powerhead. You can now proceed with the next steps in the fuel pump replacement procedure.

Drain the fuel from the vapor separator tank

To drain the fuel from the vapor separator tank, you will need to locate the vapor separator tank and drain screw. This is usually found at the bottom of the tank. Place an approved container underneath the tank to catch the fuel, and attach a drain hose to the drain screw. Loosen the drain screw to allow the fuel to flow out of the tank and into the container. Be sure to perform this task with safety in mind, ensuring the fuel system pressure is relieved and the battery cable is disconnected.

Once the fuel has been drained, you can proceed to the next steps of replacing the fuel pump on your Suzuki DF250 outboard. It is important to follow safety procedures and refer to a qualified mechanic or repair manual for a full step-by-step guide.

Remove the intake manifold

To remove the intake manifold, follow these steps:

First, relieve the fuel system pressure and disconnect the battery cable. Drain the fuel from the vapor separator tank into an approved container using the drain screw located at the bottom of the tank and a drain hose.

Next, remove the air intake silencer from the throttle body. Tag and unplug the wiring connectors from the IAC valve, the MAP sensor, and the TPS sensor on the intake manifold and throttle body.

Then, loosen and remove the bolts securing the throttle body mounting bracket to the powerhead and disconnect the throttle body link rod.

After that, remove the fuel rail and injectors. Tag and unplug the wiring connector for the high-pressure fuel pump along the head flange for the intake manifold runners.

Now, tag and disconnect the fuel inlet and outlet hoses from the fuel filters and fuel pumps.

Next, remove the bolt securing the oil level dipstick tube to the oil pan housing and carefully remove the dipstick and tube for clearance.

Then, locate and disconnect the fuel return hose from the fuel cooler at the bottom of the lower intake manifold runner.

After that, disconnect the fuel cooler water inlet and outlet hoses from the pilot water indicator on the motor case and the water return union, respectively.

Finally, using a reverse torque sequence, loosen and remove the bolts and nuts securing the intake manifold and throttle body to the powerhead. If necessary, remove the throttle body from the intake manifold by loosening and removing the retaining bolts.

Remember to grease all points, even any pivot points not disconnected, and never reuse the intake manifold or throttle body gaskets.

Loosen and remove the mounting screws

To loosen and remove the mounting screws, follow these steps:

First, for safety, relieve the fuel system pressure and disconnect the battery cable. Next, drain the fuel from the vapor separator tank into an approved container using the drain screw and a drain hose. Then, remove the intake manifold by loosening and removing the mounting screws. Typically, there are three mounting screws on most motors, but some late-model 60/70 hp/1298cc powerheads have four bolts. Once the mounting screws are removed, carefully lift the vapor separator from the back of the intake manifold as a whole assembly.

It is important to note that on 90/100/115 hp (1950cc) and 100A/115A/140/140A (2044cc) models, the fuel outlet hose may still be connected. In such cases, be sure to disconnect it before attempting to separate the VST and intake manifold.

Re-secure the vapor separator tank

To re-secure the vapor separator tank, follow these steps:

Firstly, loosen and remove the mounting screws. Typically, there are three mounting screws on most motors, but some late-model 60/70 hp/1298cc powerheads have four bolts. Once the screws or bolts are removed, carefully take out the vapor separator as an assembly from the back of the intake manifold.

Next, secure the vapor separator tank to the intake manifold using the retaining screws. Ensure that you tighten these screws securely.

If you are working on a 90/100/115 hp (1950cc) or 100A/115A/140/140A (2044cc) model, and if the fuel outlet hose was removed from the VST and the powerhead, be sure to connect and secure it now.

Finally, install the intake manifold, following the detailed instructions provided in the service manual for your Suzuki DF250 outboard.

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