4 Cyl valve setting
Tools required :
Flat tipped screwdriver
9/16 ring spanner
Setting valve clearances on your Perkins 4 cylinder motor is very staightforward. RULE OF 9. Turn crankshaft in direction of rotation until any valve is fully open. Note valve no. If valve no 8 is fully open then 9 – 8 =1 Now set valve clearance of no 1 to 012″ (0.30mm) when engine is cold. (If warm 010″ / 0.254mm). Loosen lock nut and turn setting screw.
No 7 fully depressed 9 – 7 = set clearance on valve no 2
Before setting clearances the following should be observed. Your motor has been running for many years. The face of the rocker becomes worn (Indented) from repeatedly opening a valve. Carefully machine the surface to it’s original profile.
Check the condition of the setting bolt thread (3/8″ UNF) & replace if worn – stretched. If you use a standard high tensile bolt be sure to machine bolt head markings until flat.
After fastening lock nut ensure clearance is correct as the gap tends to get smaller. Run engine until warm and recheck settings. If the rocker shaft is removed replace using a hardened flat washer under fastening nuts (1/2″ UNF).
Torque to 100NM.
Refit the rocker cover. Using a good quality contact adhesive, glue the new gasket to the cover. Use a good quality gasket sealant between the gasket and cyl head face. Use sealant conservatively. Exess sealant causes havoc with the engines oil feed system. Inspect the cover fit and knock high spots down for a uniform fit.
Ensure that both the rocker cover breather outlet & breather pipe are clean & free of obstruction to avoid what appears to be exessive blow-by through the engines dipstick.
If replacing rocker shaft ensure that the rubber grommet for oil feed pipe is installed.