ok just replaced me cylinder head all went back fine timing spot on to the dot,and ive noticed now im using shedloads of fuel got 75 miles outta 15 quids worth that cant be right! have i missed summat setting back up or ... does it just want a tune cus i changed the head?? and also the cars seems to labour a bit on acceleration as if it sorta deciding whether to go or not temp sensor and crank sensor are both brand new as well as breather mod done etc like a bit of a stutter in 1st and 2nd
well thats what the textbooks say, but its not to be trusted. the crank pulley has a "harmonic balancer" built into it. the crank pulley is made of two parts, the hub and the pulley, and these are joined by a tough rubber ring. the two halves are allowed some movement as part of their tolerance. and hence the outter ring can, in some instances, slip round making the timing marker scrap.
to time it up correctly, get the cam sprockets on their markers, then use a rod down number 1 spark plug hole (nearest cambelt end) to get piston 1 in the dwell of TDC. an alternative method is to remove the 6 crank pulley bolts, remove the pulley and there is a big fat notch on the rim of the crank sprocket, and a big notch below it in the oil pump. when these two are aligned that is TDC also. fit and tension the belt, check again that the cam sprockets point at their markers when piston 1 is at TDC.