car turns but doesnt start

i just bought car about two weeks ago had a broke harm balancer replaced it thanks to wynn carter of texastbirds.com car ran fine for 5 days then fan didnt come on and blew head gaskets now ive completly went thru the motor and got it back together and it took a while for fuel to pump back up in injectors but it finally started then it idled up and down then it finnaly just shut off then when i went to crank it again it just turns over but doesnt start if i press the gas when it is turning over it will act like it is going to start but it doesnt im thinkion the crank sensor is bad but im not sure ive only had this car about 3 weeks and it is begining to really pinch a nerve oh and it had water in pipes when it finally started does anyone think this could keep it from starting

Engine coolant in the exhaust can damage your o2 sensors but shouldnt prevent it from starting......if the crank sensor is bad the upshift light on the dash will blink during cranking.
Check your balancer and bolt....maybe it damaged the crank sensor or knocked it out of adjustment..
Can you do a koeo test and pull the codes from the ecu....

[im going to try and change the crank sensor today it took me a day to find a wrench small enough to get it off the upshift light does blink when im turning the ignition and the tach jumps all around

The crank sensor may just be out of adjustment