. . . for the responses and links (sorry for my delayed response, been out sailing for a few days)
It would seem from the SSCA forum that the experiences are mixed and I guess that probably holds true for a lot of marine gear. Since I have no idea of the history of the unit or it's maintenance regime, I have no way of knowing how it has been in it's past. It has 430 hours on the hour meter and the unit looks in very good shape, no signs of any neglect.
I bought it for the equivalent of US$550 and that includes a brand new injector pump and two injectors, a new starter and a host of other spares. The mere existence of all the bits gives me a goodish feeling about it's service history because if it was troublesome, surely these parts would have been used??
It came out of an 84 ft "super yacht" and was simply replaced as part of a complete refit. It was seemingly their back-up unit to the main genset which was also replaced with no apparent signs of neglect. The people who I got it from didn't know too much about the history but never had anything bad to say, simply that they had been instructed to replace it amongst a whole long list of other also-still-good gear.
I have no operator's manual so the content is moot, I have no connection to the manufacturer so their service response quality is also moot (but looks to be pretty good all the same).
I reckon what I'll do is carry out whatever maintenance looks reasonable and then do some saturation testing for a while. If everything checks out OK I'll make the move of ripping the heart out of my engine room to install it. If that turns out at some point in the future to be a bad choice, at least the space will be available to install something else.
Thanks again.