1. Check for scoring on the camshaft journals and measure them with a micrometer in several places to detect taper or ovality.
2. Inspect the surfaces of the bearings in the struts and housings for signs of wear in the form of grooves or scoring.
3. Where the above defects were found, replace the camshaft and its racks or casing.
4. Replace the camshaft if the cam lugs are excessively worn while replacing the cam followers.
5. Inspect the sprocket (asterisks) camshaft, crankshaft sprocket, intermediate shaft and its sprocket, timing and oil pump gears and replace if excessive wear.
6. Wash the camshaft chain with kerosene and check it for wear. Place supports under both ends of the chain so that the rollers are in a vertical position. A worn chain will sag a lot, while an unworn chain will only flex slightly in the middle.
7. Check tensioner and chain direction for wear and replace if necessary.
8. Check if the camshaft oil inlet holes are clogged, and on the M 110 engine, check the distributor drive gears for wear.