rough idle after head install

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Old 10-18-2008, 10:05 PM
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rough idle after head install

I just finished putting the finishing touches on my head swap today. I started it up and it started fine but the idle is extremely rough, the whole engine shakes from side to side. Is this a timing issue or do I have a compression issue? Its a 1981 with the 300. any input is greatly appreciated!!!
 
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Old 10-18-2008, 11:55 PM
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Try spraying around the intake-to-head surface with a can of carb cleaner spray while the engine is idling. Try each runner, and be careful not to get it on the exhaust manifold. It may be safer to do this with the motor cold, before the exhaust heats up a lot. If the idle jumps up, then the problem might be a vacuum leak.
 
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Old 10-19-2008, 05:46 AM
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Id check the the valves/rocker adjustment again.
 
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Old 10-20-2008, 08:45 AM
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I took off the valve cover again and checked my torque settings, they were all torqued to factory specs, nothing seemed out of the ordinary. I also timed it and when I'm at idle i have to keep giving it gas or else it sputters and dies.
 
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Old 10-20-2008, 10:13 AM
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Did you check for vacuum leaks?
 
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Old 10-21-2008, 07:33 AM
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Would it seem I was a jerk, if I ask, did you torque them at TDC
 
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Old 10-22-2008, 09:18 AM
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I did torque them at TDC....I finally gave up and dropped it at the mechanic, turns out I have one of the worst exhaust leaks he's ever seen. He said it wasnt due to my fault, the manifold needed to be resurfaced and my gasket was probably faulty, should have the truck back by tomorrow! Thanks for all the help guys.
 
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