I am running WVO in my 1990 Suburban. After conversion, everything ran great, although the engine ran a little rough at times. So I had the injectors cleaned and the timing advanced, but now I think things are worse: much more 'clack-clack', power not as good, even on dinodiesel.
I cannot afford to pay the mechanic every time I need to have the timing tinkered with. I am new to diesel engines and want to learn how to adjust the timing myself. Can it be as simple as rotating the injector pump in small increments (engine off) in a trial and error approach? Also, I need some guidance from anyone who is familiar with this particular engine about how the injector pump is mounted; best I can tell, it is just 3 bolts, although two of them are kind of tricky to get to.

Any help is greatly appreciated.

Jaybee - I have a wvo 6.5 and have worked on both the 6.2 and 6.5 You are correct that the IP is simply mounted on those 3 bolts. It is very easy to adjust the timing by loosening the bolts and tweaking the IP. Little changes go a long way. Advance toward driver, retard toward passenger side. There is a cast line right at the very top of the block that lines up with a case line in the IP for "rough" timing. While somewhat unorthodox, when changing the IP, I use this line to get the motor running. Warm it up. Turn it off and loosen the bolts slightly. Start it again and slowly adjust it until you get that sweet V8 sound. It should not move more than 1 degree either side of the line, unless your engine has other problems. You are probably on the wrong page for your question; for more info go to the Diesel Place and do a search for 6.2 timing - http://www.dieselplace.com/forum/index.php

JAYBEE,
you can loosen the screws on the IJ pump just so you can turn the pump by hand (but not too loose just snug enough) and while its running turn the pump very slowly until you here it smooth out a little you should only have a little black smoke at full trottle then you know its set pretty good also it should start right up when its warm as long as everything else is good.

good luck!

I've been reading not to try adjusting while running. Seems dangerous. Do you have a spec on "(but not too loose just snug enough)" Lots more info at this site.