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With or without decompression?
OK, so you need to open the carb and pull several times to get the highest reading. With the decompressor (pull start), those numbers might be OK.
Does it start and run? What is the symptom? Are you getting spark? Are the plugs wet or dry?
So, why are you testing compression?
I've got a 2008 20 HP Tahatsu w/electric start. with engine at operating temp, both spark plugs out, and throttle open I have 40 PSI Compression in top cylinder and 38 PSI in lower. This seems very low?? I looked in with endoscope pretty small view but I could see some carbon build up on edge of valveVerify your tach. Should approach 6000. What pitch do you run now?
Disassembled and cleaned carb with carb cleaner and air preasure. 3 times
I don't know anything about decompression, whether it is on or off i don't know how to tell