Next, we dropped the new pump and pump hanger back into the tank and aligned the pump hanger flange tabs with the slots in the tank.
Now the metal lock ring could be tapped into place. We installed the fuel line, plugged in our electrical connectors and fired up the engine to make sure everything was working properly before putting our interior back together. Our M5 fired right up!
Since we replaced the fuel pump we replaced the fuel filter as well. When a fuel pump wears out, carbon particles from the brushes on the commutator and metal particles from the armature are shed and tend to clog the filter. So it is mandatory to replace the filter when the pump is replaced. Especially if it is being replaced because it failed or you know it is wearing out. We picked up this Mahle fuel filter (part# 13-32-1-407-299-M67) specifically designed for the E39 M5.
The fuel filter is located under the car, on the driver’s side near the front oxygen sensor. We had to remove this plastic cover to get access to it.
The fuel lines to the filter are disconnected. Interestingly the fuel pressure regulator is attached to the filter so the return line and the vacuum reference line must also be removed.
2 comments
Never saw a fuel filter that big.
Hi, I have tried to email a couple years ago about this but the filter sock shown in page 4 is not from kit 9-401-1052. I have had a couple customers ask about this filter and this is not the correct one. Notice in the links below. The 400 utilizes an entirely different filter sock than most standard pumps. PLEASE change the part number to kit 9-1034. That kit has the correct filter for what you are trying to accomplish.
TLDR:
9-401-1052 incorrect, 9-1034 correct.
Sincerely, Your friendly neighborhood DW Employee