250 Engine Runs Terribly Update

First of all, thanks to all responders. I started the car for the first time after getting the head back from the machine shop twice on March 25 and
the 8 year old Die Hard died. I left the dome light and glove compartment light on too many times and you can only recharge these batteries so many times. I called the owner of the machine shop that did the work and though he didn't personally do the work he was adamant that the work was done to exact industry standards. He said that the valve stem heights are correct and that the tips were grinded. He said that my problem was retarded timing and to try advancing the timing. I finally got a new battery on April 3 and started the car after advancing the timing. Same exact results with 10" of vacuum, no power, and smoke coming off the engine. I removed the head and placed a long straight edge against the tips of the valves and only two tips touched the straight edge. The other tips had maybe a 30 thousandts gap. I spoke to another machine shop owner and he suspects the valves are not seating correctly. I told him that I thought that the valves were not closing when the spark arrives at TDC of the piston stroke and the problem could be incorrect valve heights. He responded that the engine shouldn't smoke if that was the problem. I also noticed that when I removed the rocker assembly with cylinder one at TDC the exhaust valve was depressed quite a bit. However, every exhaust valve was blackened with fine soot except for number 1. I also see rust around the newly machined surface of the head and suspect that water is getting on the head surface. Could the problem be water getting into the cylinders? I also checked every pushrod against the glass of my pinball machine and they are all perfectly straight.
I am bringing the head to the shop owner who suspects incorrect valve seating. He is going to perform a vacuum test on the valves and go from there. I thought it was going to be a simple matter of removing the head, having the head machined, reinstall the head, and drive away. Another machinist told me that this is exactly what should have happened.
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On Tue, 8 Apr 2008 11:35:26 -0700, "azazel scratch"

0.030" seems to be a lot of variation in stem lengths. It should not make that much difference if there is enough compressed lifter clearance to allow the valves to fully seat when running. Now that the head is back off, a vacuum test would be a good approach to determine whether the valves are capable of sealing if seated. A quick check of each valve stem length and valve spring heights may also be adviseable if they pass the vacuum check. A valve with a inadequately compressed spring will not seal when running, hence, the free and installed spring height check to compare to specs. A good automotive machinist will know exactly how to do all of this to be sure everything is to specs.
Lugnut
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wrote:

I am wondering why the basics were not done? what was the after compression test results? a comp test will tell real quick if the valves were leaking after the valve job. KB
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wondering,what did you torque the head to?
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I torqued the heads to 55, 65, and finally 75 fl-bls with a Craftsman Dial Torque wrench.
Thanks for the help you have been giving me.

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