Mazda Premacy engine cranking but not starting

Unfortunately its a case of retracing your steps. If it was working before overhaul. It must be something not put back correctly or timed properly.

Is there fuel at injectors?
Is there a spark?
Check for a spark at the correct time with a strobe light

the sparks are ok, fuel from injectors are coming out but not starting.

Ok. Fuel and spark.
Does it have a coil pack or separate leads.
It must be a timing issue check all timing,if available try a strobe light on cylinder 1 bit like the old days when timing an engine and turning the dizzy.
Make sure it is firing roughly before top dead centre.
If no marks on bottom pulley remove plug number 1 turn engine by hand with a thin rod in the hole turn it till the piston is at the top.mark the pulley and casing,
Then run a strobe to see if it sparks roughly before the marks meet.
If it does maybe its just the can timing