# Cam swap help?!?!



## Billy Loretto (Nov 2, 2016)

I just recently put a cam in my ls2 and now trying to spin the engine by the crank pulley to time it on the compression stroke on the first cylinder and it'll spin so far one way then stop and then so far backwards anyone got any ideas what it could be?


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## svede1212 (Nov 1, 2005)

Did you check piston to valve clearance?


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## Billy Loretto (Nov 2, 2016)

svede1212 said:


> Did you check piston to valve clearance?


yes everything checked out okay and it only happened recently because after i put it in i spun the engine to tighten the rocker arms


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## svede1212 (Nov 1, 2005)

I'd pull the push rods and try spinning it. If it locks up it's hitting a valve.


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## Billy Loretto (Nov 2, 2016)

svede1212 said:


> I'd pull the push rods and try spinning it. If it locks up it's hitting a valve.


okay ill try that


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## Billy Loretto (Nov 2, 2016)

is it possible that the timing is off bad enough to where that the piston is coming up and hitting a valve before it can finish its cycle


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## svede1212 (Nov 1, 2005)

Billy Loretto said:


> is it possible that the timing is off bad enough to where that the piston is coming up and hitting a valve before it can finish its cycle


Yes. Two things that should be done on a cam install is checking PTV clearance and degreeing the cam. The cam could be off when they ground it or it is installed a tooth off on the chain


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