Johnjum
24-06-2008, 10:20 PM
Having a problem timing my T4 after a head rebuild following a timing gear key failure [took a while to diagnose what had occurred!] What I need advice on is the correct position of the cam 'slot' to set the timing, the slot being offcentre to the centre on the pump end of the cam. I have made up a locking tool from a piece of flat steel so that I can get the horizontal position but it can be in two postions [ above or below centre]. Am I right in thinking that providing the No 1 piston is at TDC, the cam can be in either position because the crank turns twice to the cam's once [ combustion stroke and exhaust stoke]. I have removed the head [again] as I could'nt get the engine to run smoothly and discovered two exhaust valves were not sealing properly [ liquid test]. Not sure yet whether the valves are bent or not seated properly, the 4 new valves I originally replaced were tested OK before the re-fit. Is it possible for the cam to have twisted when the failure occurred, thus affecting the timing? I am going to get the head professionally checked, but would like clarification regarding the cam timing. The van has done 210,000 , but I've had 60,000 trouble free miles from 'her' untill the gear failure.. Advice from me now - if your 2.4 dies and the timing belt is OK, check that the belt turns with the engine, if not, it'll be the key on the timing gear sheared ! John :(