Hi everyone, I'm new to the group and seeking suggestions. I bought a non-working Allen scythe last year and have begun trying to get it running to work, rather than enjoy an elegant retirement. I have stripped and freed the cutter bar, inspected the oscillating drive mechanism but have found the engine is solid due to the piston being seized in the cylinder. Also the exhaust valve has corroded off the end of its stem. These problems are due to it being left under a hedge for many years with the spark plug missing. The engine fan casing plate is almost unreadable but towards the top right hand side is a number 25T which I think must indicate it to be a mk 25 stationary engine mounted to the machine via a flange on the shaft outlet plate. Having been watching ebay for a while and not seeing anything on the lines of valves or pistons I chanced across this group and wondered if anyone has suggestions for (a) getting the piston out and (b) sourcing a valve?