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  #11  
Old 07-31-2024, 11:52 AM
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Be sure to check for bent rods. Also check the block deck and heads to see of they are flat.
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Old Yesterday, 06:05 PM
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We pulled the heads on my 67 Nova SS with a 327 and found coolant in the cylinders. Both headgaskets were toast on my new 700 mile motor. Any ideas as to why this would happen?
After an expensive rebuild of my detonated 327 my builder/machine shop figured out the timing mark on my larger harmonic balancer from a 350 didn't jive with my 327. At TDC the mark was out 14 degrees so he scribed a new correct mark on my balancer.
This wasn't the first motor I lost to a bad timing mark. The first build didn't have forged pistons so it was toast after 40 miles. The 2nd build lasted 700 miles...fingers crossed for the 3rd build!
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  #13  
Old Today, 01:07 AM
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I'd be looking for the correct balancer for the 327. They were much thinner and lighter. That 8" balancer might be stressing the crankshaft.
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Old Today, 04:33 AM
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I would like to know which cylinders had coolant. I’d also like to know what valves were damaged, and a lot pictures.
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  #15  
Old Today, 12:08 PM
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Originally Posted by Too Many Projects View Post
I'd be looking for the correct balancer for the 327. They were much thinner and lighter. That 8" balancer might be stressing the crankshaft.
L79's, L76's, and L84's all had 8" balancers
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  #16  
Old Today, 12:09 PM
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Quote:
Originally Posted by bav70ss View Post
After an expensive rebuild of my detonated 327 my builder/machine shop figured out the timing mark on my larger harmonic balancer from a 350 didn't jive with my 327. At TDC the mark was out 14 degrees so he scribed a new correct mark on my balancer.
This wasn't the first motor I lost to a bad timing mark. The first build didn't have forged pistons so it was toast after 40 miles. The 2nd build lasted 700 miles...fingers crossed for the 3rd build!
Same engine builder?
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  #17  
Old Today, 02:19 PM
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I always check the timing mark on a engine that I'm building using a piston stop before putting the heads on. I never trust it until I verify that it's correct. I even verify TDC on a running engine that someone brings to me for tuning using a piston stop in the spark plug hole.
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