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Discussion Starter #1
After refitting cylinder head I noticed a timing issue. Having camshafts properly assigned to their marks with No. 1 at TDC the mark on crankshaft pulley is about 8 degrees ahead. The engine seems to rev well. What could be the reason, a stretched timing chain or the pulley has slipped into its rubber hub by the time?
 

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How do you know No. 1 is at TDC? Are you measuring piston position?

Pete
 

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But Mad North-Northwest
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If this is an Alfetta engine the crank pulley has a rubber damper in it that can apparently slip. This happened to someone on the board recently.
 

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Discussion Starter #4
How do you know No. 1 is at TDC? Are you measuring piston position?

Pete
Taking out spark plugs I can see piston's top in No. 1 cylinder. I tried back and forth the pulley to obtain the TDC. Actually the piston don't move in this 8 degrees (about) difference as it is the point where crankshaft rotation chang direction of conrod. Sorry if I can't expess better myself.
 

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Discussion Starter #5
If this is an Alfetta engine the crank pulley has a rubber damper in it that can apparently slip. This happened to someone on the board recently.
Yes, the pulley has a rubber insert that's why I think make such difference.
 

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But Mad North-Northwest
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Unless you cracked the pulley at the keyway, it sure sounds like the rubber. I can't find the thread where the guy had the same problem, but it was pretty recent.
 

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Discussion Starter #7
Unless you cracked the pulley at the keyway, it sure sounds like the rubber. I can't find the thread where the guy had the same problem, but it was pretty recent.
No , pulley key is ok. Rubber insert however is visible from the back and its external surface was aged and cracked. I think that rubber slip is the reason . I don't see any other reasonable explanation...
 

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Poke a pencil down #1 plug hole and rotate the engine back and forth to find the TDC. Mark the pulley with a dot of paint in line with the pointer. Then adjust your cams to your desired timing. Use the cam timing templates on Centerline's website and mark the cam caps with the pencil at the timing that you want to use. 104/104 is a good starting point.
 
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