Flame from decomp button, but won't start Stihl 066

[redandblack]

I have an older 066 that i rebuilt, and wouldn't start. I played with the flywheel timing a bit as i heard there are different flywheels for these saws, and eventually the threads on the crank were toast, so i bit the bullet and started over with a Chinese crankcase and cylinder/piston assembly. Now i am getting a slight flame out of the compression release button, and it did start twice, but mostly it won't start. The flywheel is also Chinese, as is the coil (guess it's just the plastics that are German at this point). I played with the flywheel mounting a bit (removed key, aimed for 5 degrees advance and also 5 degrees retard), and with it advanced it would close the comp release button quickly....but still didn't run.
I am guessing factory timing is OK, as i can pull it thru 4-6 rotations per pull without it kicking back, but stumped why it won't start. Clearly i am getting some fuel combustion with that slight flame coming out the comp release, just not enough to get it to rotate thru and begin the next combustion cycle. Any suggestion are appreciated!!
PS: I've rebuilt 8 Stihl's, and 1 Huskie and 1 Jonsered 920, so i usually get 'em going.

 

[Ketchup]

Plug the decomp. Passed Pressure and Vac test?

 

[redandblack]

thanks for the tips. the entire crankcase is brand new, so it has tons of compression, and i am assuming good seals. I can barely pull it thru even one rotation if the Decomp is closed.

 

[Wood Doctor]

As Ketchup implied, it sounds like that decomp valve is defective and/or doesn't seal right when up.. Replace it and try again.