Internal combustion engines use an arrangement of gears and a chain, or pulleys and a belt, to synchronize the movement of the camshaft and crankshaft as the engine rotates. Usually, when replacing the timing chain on an engine that uses this system, the gears are replaced as well. Normally, the gears can be pulled off by hand, but many times the crankshaft gear does not cooperate. In this case, a special tool is needed to remove the gear -- the three-jaw puller.
Spray the end of the crankshaft and gear with parts cleaner and wipe clean with a shop rag.
Spray the end of the crankshaft and gear with penetrating oil. Let it set for about 30 minutes.
Attach a three-jaw puller to the crank gear with the jaws slipped over the edges of the gear. The threaded rod in the center of the puller has a tapered tip that fits on the rod and sets in the center of the crankshaft. This allows the rod to be turned without damaging either the crankshaft or the rod. Thread in the rod by hand until the jaws are tight against the gear.
Use a ratchet and socket to tighten the rod. As the rod is tightened, the gear will be pulled off of the crankshaft.
