Thank you Max for the information on the air hose housing and spark plug. The spark plug is new, and I spoke with the owner yesterday who said the motor was rebuilt about 10 years ago. I reset the points gap at 0.024", where initially I found it to be 0.021" compared to stated gap of 0.027". An in between option as a starting point (No pun intended). With the timing plate, I initially set it about 1/8" from TDC (as indicated), which is about the width of the shear pin keyway, and started the mower. It ran on mid throttle, but when pushing up to full throttle it started to backfire and die, which is where I started with it after the carburettor was cleaned. I rotated the timing plate about 1mm anticlockwise and started it again, but the backfire issue was still there and again dies going to full throttle. I changed the timing two more times by moving it about 1mm anticlockwise each time with the backfire getting worse and it still starting to die when pushing to full throttle. I made 4 short videos that are between 15-50 seconds with each change, but they are all too big to link directly to the conversation, being 33-103mb each. If I go too far anticlockwise, the mower won't start, and I can't move the timing any further clockwise from where I started, so am rather stuck. Do you know what the correct points and condenser part numbers are for an engine with a 3F carburettor? All the ones I found only mention G3 & G4. Thank you again for your assistance.
