Many thanks to those members who took the time to respond to my initial enquiry.
Thanks to the advice offered we were able to start the engine and run it continuously. My only remaining query relates to the water pump. When we started the engine, water flowed freely through the engine. After a few minutes it was hot, suggesting that the pump was working adequately. Should we, as a matter of course, now replace the water pump or could we ignore the replacement for the time being?
In closing, is there any indicator which we should look for which would be a trigger for replacing the pump?
Many thanks