Gentlemen, thank you all for your replies. I believe that I have the answer to my problems. When I bought my car in November it had been standing for 25 years, yes 25 years. I fitted a new cylinder head gasket and numerous other items plugs leads etc.
I believe that the rods bent because the old petrol had somehow burnt gunge onto the inlet valve stems. OK when the engine was running but when left to cool solidified. Then when starting engine again held the valves open long enough for the rods to move away from their rocker location, then when coming back up collided and bent.
I was badly advised to leave the old fuel as it was an "old wives tale" to remove it. I have changed it now.
Rebuilding tomorrow, new gasket valve seats machined, valve sealing faces machined and lapped, new petrol, new oil new filter and hope in my heart.
