One of the better Blackstones I have had over the years and passed on, it came from a property at Jerrawa creek near Canberra/Yass district, a sketchy video of it running, the knock was the water pump binding. https://www.youtube.com/watch?v=jUtG0-7SpZU
thanks for that harry i purchased it in 2013 and bought it to WA runs nice i would like to put a better water pump on it . also it bangs very loud out the exhaust acasionaly. not sure what causes it
nearly time to take it out again.
Nice engine Shane.
Sometimes unexploded gas can explode in the muffler. I have had it happen, I seem to remember there was rust particles in the carburetor and some times partially blocked the jet causing a misfire with a build up of gas in the muffler and exploding just as the exhaust valve opens after ignition in the cylinder. My hot bulb Hornsby also started doing it when the hot bulb cracked. A new hot bulb fixed that one.