Finally back working on the Zafira. As there was no compression in cylinders 1 and 3 I have taken the head off and there are marks on the pistons (all of them) where the inlet valves have hit the pistons. Before I decide if it is worth to continuing with the rebuild I would like to know if there is any further damage. I have remove the sump to remove pieces of broken cam chain guide. My question is whether I can check if there is any bottom end damage whilst the sump is off as there may have been a bottom end noise when the car was running? Is there an easy way for an average home mechanic to do this?