I'll start at the beginning, bought a 5.3 a year or so ago. Running engine,
sat on a motor stand inside until a few weeks ago. I changed the oil pan and the old one was nice and clean, pulled the valve covers and again everything was nice and clean looked like the oil was change regularly.
Went to put the motor and trans in car, but when I tired to bolt up the
torque convert to the fly wheel the motor would only turn 2/3 of a turn.
Finally got a chance to pull the heads last night and this is what I found.
It looks like the carbon build up dried up and fell off, enough to stop the motor from turning.
Is this common???????????

 

Not common at all, though glad that's all it was.

Sounds like the tune was way off or the injector spray pattern was fubared.

 

Glad you figured it out, but did you personally see the motor run before you bought it?

 

Me no, It was sourced from a good ( yes a good ) friend.

 

Vacuumed out the crap, spray in un a little WD40 and turns free now.

 

Can you post some better pictures...???

Looks like a lot of rust/carbon/scratches in those cyls for something I would just button up and run...(and I'm the king of running high mile junk).

 

OK, never mind...I saw your other post asking about shops...excellent idea.

 

Multiple threads, same question/issue. Here's the main one: https://ls1tech.com/forums/generatio...f-ed-am-i.html