Timing problem?

Hi Ihave a 93 escort with a 1.9L engine. The thermostat froze up while my wife was driving it and of course it cracked the aluminum head. I ordered a rebuilt head head and installed it. The problem is now I can't get it to stay in time. I turned the crank to make sure it was lined up TDC before I installed the head. Line up the timing mark on the cam shaft sprocket with the mark on the head. Installed the belt in a counterclockwise direction. Turned the engine over twice to make sure the marks lined up and they did. Did this several more times to be certain even gently put a screwdriver in the NO1 sparkplug hole to be certain it was TDC. Everything good I start it up and fires right off. Shut it off and the marks no longer line up. Irepeated this process several times and same result each time. Please Help!!!!!!!!!!!!

Does the car start and continue to run? If it does and the belt is new then there shouldn't be a problem regardless of whether they line up or not.

Is your tensioner loose??

weel that seems to be a concern of mine also. The torque is supposed to be between 17-22 ft-lbs. If it is torqued down how can it adjust to the stretching of the belt over time.

thanks Jet-Lee I went out and tightened it up and sure enough no more trouble. I am by no means a mechanical person but with a book and help from people like you Iwas able to do it. Thanks again.