COUPLING-EXH-YM 3256053 - Caterpillar

Illustration 1 g01227078
Fuel injection pump timing mark (1) Timing mark on the fuel injection pump (2) Timing mark on the engine block
Timing marks (1) and (2) on the fuel injection pump indicate the pump position relative to the timing gear. Each mark on the scale represents a change in timing of six degrees.
Illustration 2 g01227082
Adjusting fuel injection pump timing For 3046 Engines Only (X) Direction of retarding timing (Y) Direction of advancing timing
Loosen the retaining bolts. Rotating the fuel pump toward the engine advances injection timing while rotating the fuel pump away from the engine retards injection timing.
To check the fuel injection timing, disconnect the fuel injection line from the fuel injection pump. Loosen the clamp and remove the delivery valve holder. Remove the valve spring and the stopper from the delivery valve holder. Replace only the delivery valve holder. Install a new fuel line to the delivery valve holder.
Turn the crankshaft until the No. 1 piston is approximately 60 degrees BTC on the compression stroke.Note: Check the valve lash with the No. 1 cylinder at the top center position. This ensures that the cylinder is on the compression stroke and that the cylinder is not on the exhaust stroke.
Illustration 3 g01227084
Crankshaft pulley timing marks
The crankshaft pulley contains a scale that has a range of 0 degrees to 40 degrees. The first mark on the scale represents 0 degrees. Each mark on the scale after the first mark represents a 5 degree crankshaft rotation.
Use a suitable container to catch any fuel that might spill. Clean up any spilled fuel immediately.
Illustration 4 g01227085
Checking for fuel flow (3) Fuel priming pump
Operate the fuel priming pump. Rotate the engine crankshaft until the fuel stops flowing. Read the number of the timing mark on the crankshaft pulley that is indicated. The number of the timing mark should be within 1.5 degrees of the number on the emission sticker. The emission sticker is located on the top of the valve cover. Refer to the Technical Marketing Information (TMI) for other technical data. To correct the fuel injection timing, rotate the fuel pump. Refer to Step 3.