Hi.
There's usually three things to look at; compression, spark and fuel delivery. Sounds like compression is okay (it usually is) but both spark and fuel delivery are in question here.
Do you feel compression when you pull on the recoil starter? If you do a compression test, look for at least 90 psi in each cylinder.
What kind of test was done to determine the spark was good? If spark is good the pulser coil is good. So, I think we need to understand the tests that were done to indicate good spark.
All that aside, if spark is good, send a squirt of premixed fuel (please, no ether) into the carburetor intake. Close the choke and pull starter two or three times. You should get a pop. The ether burns too hot for this hardware and can damage the piston. It sounds tempting but its not for these two-strokes. Use the same 50:1 mixture that fills your tank.
If you can get the serial number we can get right down to business on troubleshooting. Serial number is located on the transom bracket or on an aluminum cap plug on the engine block.
Thanks,
J
