Chevrolet Repair: timing belt, isuzu truck, valve job

Question
i have that 1992 isuzu truck, 4cyl,5spd,2.3 ltr engine, you helped me out greatly last time...so here i am again.  i replaced the head on it about a month ago, thenlast mon.(26th) i pulled my spark plugs cause it was running pretty rough,the no.2 was oily but 1&3 were like new, i put them back in the next morning it sounded like it had a rod knocking, i cut it off &towed it home. i pulled the plugs again and they are all smashed and my timing belt appears to be a tooth off. what happened and what do i do now? new motor or block. i appreciate your time and thank you much.   ron newburn   newburn@sptc.net

Answer
Hi Ron,
The timing belt being off, weather a notch, or all the way, wouldn't cause anything to hit the plugs. It could cause the piston to hit the valves, though, and knock a bunch of carbon and stuff loose, but I haven't seen it smash the plugs.
You could get by with a valve job and new belt, if it didn't bust the pistons too bad.
Van