* Mechanical Fuel Pump: If your truck has a mechanical fuel pump (most common on older diesels), it's usually mounted on the engine block, near the distributor (though there isn't a distributor on a diesel). You'll likely see a small, usually round, pump with a push rod connection.
* Electric Fuel Pump: Some 88 F-350 diesels might have an electric lift pump *in addition* to a mechanical pump, or even solely rely on an electric pump. If it's an electric pump, it could be located near the fuel tank, inside the tank itself, or possibly along the frame rail near the tank. This is less common for that year.
To find it definitively:
1. Consult your owner's manual: This is the best resource for your specific truck's configuration.
2. Check your engine bay: Carefully look around the engine block for a small pump with fuel lines attached.
3. Look near the fuel tank: If you can't find it on the engine, check under the truck near the fuel tank. This is especially true if you hear a humming noise from that area when the ignition is turned on.
4. Use a parts diagram: Obtain a parts diagram for your specific year and engine (e.g., 6.9L IDI or 7.3L IDI) from a Ford parts website or a reputable online auto parts retailer. These diagrams show the location of all components.
Remember safety first! Disconnect the negative battery terminal before working around fuel components to prevent sparks. Diesel fuel is also flammable, so work in a well-ventilated area.
