It's been laid up since october and will be going for it's first service next week so I decided that I should get it running. Fitted the battery and the tank (it had been emptied and kept indoors) put fuel in it and fired it up. It started readily, however it was quite rattly. I'm guessing (I've no experience of OHV / hydraulic tappet motors) that this is a characteristic of hydraulic tappets?