Fingers crossed. Our local marine engineer visited today to look at our poorly generator. From my description of the problem, which we had during our trip out in October, he suspected air getting into the fuel line. A quick check around with a couple of spanners and he discovered that the pipe fitting on the top of the fuel tank, which is underneath the generator, was a bit loose. Having explained that I had replaced the pipework for the cooling system at the start of his visit, he wondered if I had loosened it accidentally when fitting the new pipework, which was very close to the fitting, and I did struggle to get the new pipework in around that fitting. This tied in, as the problem had started after I changed the cooling pipework. He also tightened a few other joints whilst he was at it Hopefully this has fixed the problem. We will know when we set off hopefully next month for our Spring/Summer cruise.