Originally Posted by mayco
I hope this isnt a stupid question but, once the valve cover is off, can you actually get your head in there to see top dead center on the damper? It just looks awfully tight. Can you get a socket on the damper retaining nut to turn the motor? Please forgive my lack of knowledge. (Or at least put up with it)
Thank you as always,
No such thing! I have got some stupid answers though.
Can't speak for the Isuzu but cummins has 2 positions that you identify the open close sequence and both valves being unloaded on two companion cylinders. You can usually rotate the engine by the alternator nut because it easy to get at while you can observe the rockers. There's a chart telling what valves to adjust. Make a mark on the balancer and rotate one turn and adjust the rest. Cummins says to adjust them with the engine below 100 degrees and above 50 I believe. I'm sure there is a similar procedure for the Isuzu.
These engines generally have solid lifters. As the valves wear into the seats the gap loosens up and they start hammering causing wear. It can also reduce the travel of the valve and effect performance a small amount. Cummins says adjust them every 20K miles.