chevy k1500, popped then quit

mmm, check if the cam and crank turn...perhaps the timing chain has slipped or has broke~

Checked the timing chain, it's tight. The marks on the crank and cam line up perfectly at top dead center on #1 piston

with sparkplugs in, engine turns over 3 times then seems to bind up. with plugs out it will wind over as long as you turn the key

Popped then quit...it "dead-heads" when spark is put in....the spark timing is off...perhaps the distributor was accidentally bumped forward in timing~ see if (god forbid) the distributor gear went crunch...but that would not spark too soon...but would check the distributor to see if the position is OKAY~

Thanks, I'll try tomorrow it's pouring rain right now. don't have a garage.