MBE 900 - Section 2 Fuel Filter Housing | Detroit Using a 36-mm socket wrench insert, unscrew the cap on the main fuel filter and remove it, along with the filter element. Pull both the cap and the filter element a short distance out of the filter housing. See Figure "Removing the Filter Housing". Allow the fuel to drain off the filter into the housing. How to Change a Detroit Diesel Fuel Filter | It Still Runs How to Change a Detroit Diesel Fuel Filter by Gregory Crews . Do not wrench tighten as this could strip the threads of the filter or filter housing. Repeat steps if the Detroit Diesel has a secondary filter. Step 5. Start the truck and allow it to idle for five minutes. Inspect for any leaks.