Remove the round cover on the front of the engine. The gear on the front of the injection pump will need to be pulled of with a puller. The gear has two metric threaded holes. I use a small steering wheel puller. Loosen the large nut in the center of the gear and remove the flat washer behind it. Reinstall the nut loose. You want the nut on the pump so the gear does not pop off and come out of place. Do not remove the gear out of the timing cover. You will lose time. You can put the flywheel on top dead center before removal. You can line up the timing mark inside the injection pump through the small oblong cover. After the gear is pulled just remove the three retaining nuts on the back side and the injection lines. If the pump is just leaking out the top as is the most common problem that can be repaired without removing the pump.