I sprayed a small amount down the air intake hose, which didn't do anything, so I sprayed a small amount in the carb where the air intake connects, also did nothing.
I tested my plug in a running mower and it works fine, so I've narrowed it down to lack of compression or ignition/timing.
I will purchase a compression tester on the weekend and measure the compression.
I'll keep you updated with the results.
