Have a 02 blaster comp is round 145, has good blue spark, but wont start. To eliminate a fuel issue ive tried putting fuel directly into the cylinder occasionally sounds like it wants to start but wont. My leak down tester needs new regulator so unable to perform that test. Any ideas welcome.

 

Just my two cents,I'd get the leak down tester repaired or start replacing crank seals,head and base gasket,plus you can't over look the engine case itself for leaks in the crank shaft area of the case. It has to have good top end compression, a good bottom end seal to compress the air/fuel mixture and shoot it up the transfer ports for ignition.