Im working on a 97 with the 5.7. When I try to start it, it kicks back and it seems like its struggling to turn over. After it starts it seems to run fine. I dont know if any of this matters but it has a new flywheel, starter and timing chain. Any suggestions are greatly appreciated.

 

sounds like the timing chain/cam timing or ignition timing is out. did the problem start after timing chain replacement? If the ignition timing is xs retarded you would have a long crank time before starting. if to advanced you would have a slow, uneven crank over.

 

1997 gmc 5.7 hard to start. turns over like timing is off, then will start. replaced battery,starter,battery cables