1998 Chevy Lumina Need some ideas on what to look for?????

1998 CHEVROLET LUMINA
132,000 MILES • 6 CYL • FWD • AUTOMATIC
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MARTWEIN
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I replaced the intake manifold gaskets on this car. I made damn (3-times making sure) that the pushrods went back in the same spot. I put it all back together and when I tried to start it, it had no compression. I immediately tore it back down to the pushrods. I took each pushrod and measured them individually. The exhaust rods were 6 inch and the intake were around 5 3/4. They were installed correctly. I put it back together and still no compression? I did a compression check on each cylinder. (1=65) (2=90) (3=90) (4=120) (5=150) (6=60). I know each cylinder should be over 100psi. Any ideas of why I would have no compression when the pushrods were installed correctly? I should not have any bent valves? I also torqued the rocker arms to 124 in lbs with an additional 30 degrees. I have also read it should be 89 in lbs with an additional 30 degrees. With 124 are my valves too tight?
Apr 28, 2009 at 9:55 PM
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DOCFIXIT
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124 and 30 is correct.Recheck that you are getting the shorter one on the intake and longer on exhaust.
Injector will locate the rocker for intake.
Apr 29, 2009 at 10:34 AM
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MARTWEIN
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124 inch lbs is TOO TIGHT on those valves. I re- torqued them to 89 inch lbs with an additional 30 degree turn and it fired right up. All Data's TSB is incorrect.
Apr 29, 2009 at 12:57 PM
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DOCFIXIT
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That's good to know Mitchel said 124. Checked all Gm TSB they do not mention any change. is this a 3.1L?
Apr 29, 2009 at 3:16 PM