I am working on a 1998 Trailblazer and it has me at wits end...It has been bored with all new top end and all new crank bearings and seals...It has fire and have cleaned the carb time and time again...Just wont crank...I even tried putting gas in cylinder to make it fire off with no luck...Any help would be greatly appreciated...I fell like it is maybe a weak fire issue but see what yall think...THANKS STEVE

 

Gotta have good compression,I'd recheck it even with a new top end. Good spark.Pull the plug cap and see if you have a good spark grounding it out to the cylinder. Air supply and fuel.One thing that can cause problems is the reverse limiter if it starts to short out.Pull the black wire from it at the circuit board and see if it starts.Leave the black wire unplugged any way.If this doesn't help and you think it's spark related,best to have a manual that gives you the resistance specs on the stator and coil.If the stator and coil check out,then a cdi could be faulty. http://gh-ftp.com/ORV%20Manuals/Pola...e%20Manual.pdf