It's amazing how some motors just wont die,they'll run forvever but poorly,even if you try to blow it up on puropse,or just dont care if it does..

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We had a '6o or so Chevy C-60 truck at the junkyard,that had a 235 or 261 straight six in it,it had a long flat bed,and a home made crane setup on the rear of it that was operated by a PTO winch mounted near the cab end of the bed..it looked like another 2 ton truck's frame was used to build the "boom" part.
It was scrapped because evidently the radiator leaked and they kept adding plain water,no anti-freeze,and the engine block split wide open right near the center,under the head,a good 1/2" wide split!--you could see the piston in that cylinder sliding up and down!..yet it would run pretty decent a good 20 minutes before it started screching and would slow down like it was binding up...
To get it started from a cold start,we had to pour about a cup of oil down the carb,while cranking it,then chase that with a shot of gas..once it fired up and burned the oil off,it actually ran pretty well,on 5 cylinders..the split one pumped air like a compressor,sounded like an engine with one spark plug left out..
We just had the valve cover lying on the head with no bolts for the duration we used it too..the bolts all were busted off in the head..we tied a cinder block on top of it to keep it from bouncing off!..
We used that truck often to load cut up cars,engines,and other heavy things into customers trucks,or to load up the ramp truck with cars to be squashed at another location...
I was always amazed that thing always re-started after you let it cool down,it was good for another 20 minutes or so,which was about as long as we needed it to use,so we never bothered trying to put some other engine it it!..we asked the boss many times "-Can we put this engine & trans in it",and he'd say "NO!--if its still running,just USE it!"..