As this is a follow on , not a duplicate posting,
Does the engine turn by hand?, if so it is not hydro locking.
Is your starter man enough for the job , if it is turning by hand then try moving the prop back till it stops, then spin the starter up and push it onto the spinner and see if it turns the engine over, try it with full throttle as well as at idle.
You do need to prime the engine, put your finger over the carb or exhaust outlet (with glow disconnected) and flick the engine over untill fuel delivery pipe is full, then a couple more flicks, then remove finger, a couple of flicks by hand, connect glow plug , throttle closed fully but trim open fully, and flick it over by hand, should start within a couple of flicks. If it is not turning over, check you have not put a long reach glow plug in and the piston is not hitting it.
Does the engine spin over on the starter when it is completely dry, with no fuel or priming? or if it is that tight you can crack the glowplug loose and start the engine, then tighten it once it is running.
One other thing, is it an ABC engine, if so you may need to heat the head to expand the bore to get the piston to move freely, the fuel may be cooling it down to much and the bore is to tight, try holding the head in your fist for a couple of minutes or if possible a heat source of sorts ( not naked flame) then see if it spins over.
So many variables it is difficult to give you a direct answer, but if you keep reporting back I am sure we can all help you eventually.