3306C Truck Engine Caterpillar

The starting point for all timing procedures is with the No. 1 piston at the top center position on the compression stroke.

Note: The engine is seen from the flywheel end when the direction of the crankshaft rotation is given.

1. Remove the starting motor.

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Illustration 1	g00319605
(1) 5P-7306 Shaft housing. (2) 5P-7305 Gear Timing Bolt. (3) Timing bolt.

2. Install the tools in Illustration 1, as shown.

   Note: If the flywheel is turned beyond the point of engagement, the flywheel must be turned in the direction that is opposite of normal engine rotation. Turn the flywheel by approximately 30 degrees. Then, turn the flywheel in the direction of normal engine rotation until the timing bolt engages with the threaded hole. When the No. 1 piston is at the top center position, this procedure will remove the play from the gears.

3. Remove the valve cover.

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Illustration 2	g00319609
Removed Valve Cover (4) Rocker arms.

4. Rotate the crankshaft clockwise by approximately 30 degrees.

   This step removes the free play from the timing gears after the No 1 piston is put at the top center position.

5. Remove the plug from the timing hole in the flywheel housing.

6. Rotate the crankshaft until a 3/8-16 NC bolt that is 50.8 mm (2.00 inch) long can be rotated into the flywheel through the timing hole in the flywheel housing. The No. 1 piston is now at the top center position.

   Note: If the crankshaft turns beyond the top center, repeat Step 4 and Step 5.

   Now, No. 1 piston is at the top center position.

7. If No. 1 piston is on the compression stroke, all of the valves should be closed.

   You can move rocker arms (4) up and down with your hand.

If No. 1 piston is not on the compression stroke, follow these steps:

1. Remove the timing bolt.

2. Rotate the crankshaft counterclockwise by 360 degrees.

3. Install the timing bolt.

   The No. 1 piston is now at the top center position on the compression stroke.