REMOVAL & INSTALLATION
Inline 6 Cylinder Gasoline Engines
See Figure 1
- Remove the front cover.
- Slide the crankshaft oil slinger off the front of the crankshaft.
It is a good practice to mark the timing marks with white paint before proceeding.
- Remove the camshaft sprocket bolt.
- Remove the timing chain with the camshaft sprocket.
- Turn the crankshaft to line up the timing mark on the crankshaft sprocket with the centerline of the camshaft (without the chain).
- Install the camshaft sprocket and chain. Align the timing marks which were painted earlier.
- Torque the camshaft sprocket bolt to 35 ft. lbs. (47 Nm) for the 6-198 and 6-225; 20 ft. lbs. (27 Nm) for the 6-251.
- Replace the oil slinger.
- Install the timing case cover.
See Figures 2 through 7
- Remove the front cover.
- On 238, 318, 383, and 360 engines, remove the camshaft sprocket lock bolt, securing cup washer, and fuel pump eccentric. Remove the timing chain with both sprockets. On 400 and 440 engines, remove the camshaft sprocket lockbolt, then remove the timing chain with the camshaft and crankshaft sprockets.
- Place the camshaft and crankshaft sprockets on a flat surface with the timing indicators on an imaginary centerline through both sprocket boxes.
- Place the timing chain around both sprockets. Be sure that the timing marks are in alignment.
- Turn the crankshaft and camshaft to align them with the keyway location in the crankshaft sprocket and the keyway or dowel hole in the camshaft sprocket.
- Lift the sprockets and timing chain while keeping the sprockets tight against the chain in the correct position. Slide both sprockets evenly onto their respective shafts.
- Use a straightedge to measure the alignment of the sprocket timing marks. They must be perfectly aligned.
- On 238, 318 and 360 engines, install the fuel pump eccentric, cup washer, and camshaft sprocket lockbolt and torque to 35 ft. lbs. (47 Nm) If camshaft end-play exceeds 0.010 in. (0.25mm), install a new thrust plate. It should be 0.002-0.006 in. (0.05-0.15mm) with the new plate.
- On 400 and 440 engines, install the washer and camshaft sprocket lockbolt(s) and then torque the lockbolt to 35-40 ft. lbs. (47-54 Nm). Check to make sure that the rear face of the camshaft sprocket is flush with the camshaft end.
CHECKING TIMING CHAIN SLACK
See Figures 8 and 9
- Position a scale (ruler or straightedge) next to the timing chain to detect any movement in the chain.
- Place a torque wrench and socket on the camshaft sprocket attaching bolt. Apply either 30 ft. lbs. (41 Nm), if the cylinder heads are installed on the engine, or 15 ft. lbs. (20 Nm), cylinder heads removed, of force to the bolt and rotate the bolt in the direction of crankshaft rotation in order to remove all slack from the chain.
- While applying torque to the camshaft sprocket bolt, the crankshaft should not be allowed to rotate. It may be necessary to block the crankshaft to prevent rotation.
- Position the scale over the edge of a timing chain link and apply an equal amount of torque in the opposite direction. If the movement of the chain exceeds 1 / 8 in. (25.5mm), replace the chain.