Used engine, been sitting

[Barbarino]

I recently got a 2003 6.0 lq4, past owner says it has sat since 2011, has wiring harness and drive by wire, and computer. Have .not checked to see if it turns freely, thinking I should spray some WD40 before turning the crank. If it turns freely, gonna replace seals and gaskets, etc. Are my plans good... is there a better way to get the parts rotating before starting the engine?

[SMWS6TA]

was it covered (sealed) or left outside exposed? it really makes a difference. may want to run a bore scope thru plug holes see if any rust in cylinders before you spray wd40 and turn over. if there's rust, a mixture of cheap regular trans fluid (non synthetic) and diesel, let sit for 24-48 hrs in cylinder. of course change oil after

[Whamhammer]

I recently got a 2003 6.0 lq4, past owner says it has sat since 2011, has wiring harness and drive by wire, and computer. Have .not checked to see if it turns freely, thinking I should spray some WD40 before turning the crank. If it turns freely, gonna replace seals and gaskets, etc. Are my plans good... is there a better way to get the parts rotating before starting the engine?

I agree with SMWS6TA, borescope first, then soak the cylinders, when you do turn the crank (after draining the fluid out of the cylinders of course), do it without the plugs in it.

If it's been sitting for over a decade, I wouldn't be surprised if it needs a slight honing of the cylinder bores, which means new pistons; probably a good idea to get new pistons, especially ones that increase the compression ratio, as I believe the compression ratio of a LQ4 was below 10:1