Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
1985 BMW 524tdFACTORY OEM SERVICE PROCEDURE
Bleeding Fuel System
NOTE:
Fuel system must be bled before starting engine each time fuel system has been opened or vehicle must be driven until fuel tank is empty.
- Loosen vent screw. Vehicles with a fuel transfer pump will not have a manual pump. Turn ignition switch to "Engine Running" position and let fuel transfer pump run until fuel escaping through bleeder screw hole is without air bubbles. Start engine. In most cases bleeding the fuel feed and filter will be sufficient.
- Loosen coupling nuts (6) on fuel injectors with Special Tool (13 5 020). Operate engine starter until fuel escapes at connections of fuel injectors. Then tighten coupling nuts.
- If fuel does not escape at one or more fuel injector connections, disconnect pertinent lines on the injection pump. Then loosen pressure line connection enough that spring located inside is relaxed (about 5 turns).
- Start engine until fuel escapes. Connect or tighten pressure valves and injection lines on injection pump again. Repeat bleeding procedures on fuel injectors.
- If fuel still does not escape at pressure line connections or electric fuel shut-off, the electric fuel shut-off valve could be defective.
- Check by accelerating slightly to close spill port on governor valve in the injection pump. Make sure that electric shutoff valve has electric power.
- Remove plug on injection pump head. Fuel should escape at this point when operating the manual pump or electric transfer pump. If no fuel escapes, the shutoff valve is defective and must be replaced.
Factory Service Tools
Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
Disclosure: Verified tool recommendations may earn an affiliate commission at no cost to you.
When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- β’ You smell fuel, burning insulation, or see smoke.
- β’ Brakes feel soft, pull hard to one side, or make grinding noises.
- β’ The engine overheats, stalls repeatedly, or misfires under load.
- β’ You are missing required tools, torque specs, or safe lifting equipment.
- β’ You are not confident in the next step or safety outcome.
