Is there anyone in Blackburn area who can help with an engine problem on my Marlin. It's powered by a Briggs and Stratton 35 hp vanguard V twin. It will only tick over on 1 cylinder. But appears to run on both when revs are high. It was running fine a few weeks ago when I was out from knott end. Until the fan blew up. I suspect one of the coils. As both plugs have been replaced. Any advise would be appreciated