For the technically minded, here is an account of our latest engine issue.
Faced with sudden overheating we found that there was no salt water flow. Having checked the inlet and strainer for obstruction, we opened the Jabsco pump and found that although the impeller was perfect, the wear plate behind it had fractured. Only half of the plate was visible in the pump chamber, so we dismantled all the hoses looking for the remainder. A few de-zincified fragments turned up in the oil cooler, but that was all. I decided that this was an old injury and that failure of salt water flow was probably caused by a failure of self-priming..
Now for the ingenious bit. Becalmed and it being too early for serious fiveses we decided to manufacture our own wear plate. Looking for a sheet of something suitable Ian came up with a piece of tupperware, which we cut to fit. All reassembled, we started the engine again and, hey presto, we had excellent exhaust water flow.
A very satisfying 8 hours of labour, for which we rewarded ourselves with a fine sunset imbibulation and comestibles.