Motor seized?

Attempting to get my 91 back running after sitting many years. When I go to start with a fresh battery I turn the switch and get a solid "thunk"

Took the belt off and all accesories turn freely but can't spin the crank one millimeter....


Truck ran fine prior to the rear end letting go hence the lay up an letting it sit for a week turned into a month turned into 5 years. It had been cranked and turne over ever couple of months up until a year ago an it just slipped off the radar.


So I remember several old car we used to have this problem we would drag them and pop the clutch and they would break loose. This truck is a turbo 350, will it work the same if put in gear?


Pulling the plugs now and putting mystery oil in...

alrighty then :(

Yep it's seized. Nope don't try to bump start it. Every day pull the plugs, put some oil in there and try to turn it by hand with a long ass bar. Eventually it will give. I've had to do this with 3 or 4 old tractor engines.

^ good advice, thats what i would try and do. put some penatrating fluid in the plug holes, let it sit for a day or so, then try and turn it over, work with it dont force it. she'll eventually move

thanks guys, still trying not giving up yet :D