Valves Adjusted, Strange Results

[MMcCallie]

Hadn't had my valves adjusted in roughly 50,000-60,000 miles and was talking to my mechanic about it and he suggested they be adjusted every 10,000 miles. I was telling him how I'm making about 10 psi less boost than a year ago and my fuel economy has dropped a few mpg.

I've heard lots of different numbers as to when they should need adjusting but he said the engine should purr at an idle perfectly smooth, like it used to but no longer does and that convinced me. So he adjusted the valves and told me both the intake and exhaust valves were all quit a bit off and were badly in need of adjusting.

Took it for a test drive and am making even less boost, max of 35.9 psi at about 100 mph up a mountain, EGTs just under 1,700 F. Previously seeing 36.7 psi with EGTs reading over 1,900 degrees. I wonder if my BD X-Monitor is inaccurate. Anyway, still lots of smoke even at max boost.

Strangely, boost decreased the more I drove. Boost was also far slower to respond and climb. Between stop lights I was no longer seeing any boost, even up to 45 mph unless laying very heavily into the throttle, even then only in the teens but tons of smoke. Another thing I noticed was that the engine does seem to be smoother and sounded different under heavy throttle. No longer as pingy, more of a deep, mellow roar like a V8.

Mechanic had waited until the engine was cool to adjust. Says he set everything by the book. since the engine runs smoother, I assume he's right. He's suggesting a boost leak since I've had low boost for a while. Last fuel filter swapped a month ago was filthy so we'll swap that out too.

Is it possible for the engine to make more smoke and less boost after a valve adjustment? Engine still seems so responsive so I don't suspect the timing has slipped but we can check that. He said we'll isolate the boost tubes and the intercooler from the turbo and check for leaks.

If I still have low boost after we figure things out, how do we adjust the wastegate actuator rod on an HTT HTB 62/12 for more boost? Can't even see it from above.

Thanks for any ideas,
Matt