she drove as normal as you can expect for a 82 300sd that has been run hard and put up wet 300,000 + miles as odometer quit years ago. the 617 had alot of blowby and oil leaks [crankcase press] being the faithfull old girl she was she made it home and wouldnt fire next morning.checked compression below par, less then 300 psi in all 5 holes spining her with 24 volts my questions are #1 how does one check inj. pump and cam timing? #2 does the piston "kiss the valves" in this eng? its a tough call as to whether or not its cost effective to replace chain and tensioners as the rest of vehicle is badly deteriated. many thanks 4 any info or a referal to another site. regards butch