Has anyone ever had motor sieze up after restart from doing injectors in 8.1 chevy 2001 . And why ?

Hi I haven't personally had this happen , but it has been known to, this could be a few things, normally either the injectors have let to much fuel in ie they are open all the time and when you switch on ignition the barrels fill with fuel and it has hydro locked the engine, best thing to do in this case is, disconnect battery, loosen injector pipes and let the pressure off, reconnect battery then try again, if it does the same you have problems with injectors, another thing that would do it is timing..have you adjusted something that has put the timing off? say replaced the timing belt or something like that?, the other one is, are they the correct size injectors? are they to long? some people make the mistake by buying second hand injectors and find they are from a totally different engine and are to long, and the piston will not travel fully hence it stops and will not go further, but this is a long shot answer, anyway hope its been of some use to you..