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2008 Avalanche LTZ - Dropped Valve?

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Old Oct 2, 2014 | 07:13 PM
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Default 2008 Avalanche LTZ - Dropped Valve?

Hello everyone. I am new to the forum. I recently replaced the valve seals on my 2008 Avalanche LTZ. Long story short, I forgot to run compressed air into the cylinder and the valve dropped slightly. The kicker is, that the valve only dropped a few inches and not all the way. I can still see the valve stem, but cannot grab it. I put compressed air in to prevent it from dropping further. Is there any way I can get the valve back up? What if I turn the crankshaft? Any other suggestions? Am I pooched? Thanks
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Old Oct 2, 2014 | 10:55 PM
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First try a magnet, if that doesn't work you can carefully crank the motor over by hand at the crank pulley and let the piston push it back up far enough to grab it....I'd try the magnet first, just make sure it's a good powerful one!
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Old Oct 2, 2014 | 10:56 PM
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(Edit John B beat me to it lol )I would try to turn the motor slowly by hand and see if you can get it to come up or try a stick magnet and see if has enough pull to bring it back up.
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Old Oct 2, 2014 | 11:00 PM
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Another thing that may work with some creativity would be to use a shop-vac and seal it against the head and see if it has enough vacuum to pull it up while using air in the cylinder. Not sure if it will work but it sounds good lol.
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Old Oct 3, 2014 | 08:18 AM
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Definitely try the magnet first and if you are unable to pull it up with magnet I would turn the motor using the crank bolt. If you have to turn the motor over make sure you are turning the motor over the right way so the piston will be on the up stroke and not the down stroke.
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