2001 vauxhall corsa 900cc 3 cylinder?

yes the altinator, water pump engine support and bottom pulley have to be removed,then remove sparkplug cover and the cam cover.then you loosen all the screws around the timing cover including the ones from the sump up.There is a bung on the lower O/S of the block that you remove that allows you to enter the tool into the crank to locate TDC ,when this is done you place another timing bar across the groves on the back of the camshafts. This is the timing set and held. Then you push closed the chain tensioner and retain with a a pin that comes with the timing tools.you should then be able to remove the chain if not then loosen the sprocket on the front cam as it does not carry the ignition timer.You rebuild in the same order. This is not an easy or simple job and you would need some technical know how and the proper tools and timing tools to work at these small engines.

rob
November 2011