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Oct 29, 2023 | 02:47 PM

Remy_

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Top dead center

I am removing the heads to replace my head gasket and was wondering if I really needed to set the engine to TDC or if there were any advantages in doing so.

Oct 29, 2023 | 05:55 PM

mmartinez

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From: Espanola New Mexico

I don't know why you would need to have the engine at TDC for head gasket replacement, you do need the engine at TDC when replacing a cam shaft or timing chain.

Oct 30, 2023 | 08:55 AM

schmuckingham

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Older distributor motor, sure. With this as long as the cam is not removed then it doesn't not matter for removal.

Oct 31, 2023 | 10:04 AM

vettenuts

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From: At the beach in little Rhody

Yes, should be a TDC. It's for rocker tightening sequence later when you are re-assembling the valve train. I would set it and mark your damper with a dab of paint.

Oct 31, 2023 | 02:02 PM

mmartinez

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Learn something new everyday.

Oct 31, 2023 | 05:20 PM

C5MSG2004Vert

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Quote:

Originally Posted by vettenuts

Yes, should be a TDC. It's for rocker tightening sequence later when you are re-assembling the valve train. I would set it and mark your damper with a dab of paint.

This is what I found. For tightening rocker arms.

Set motor at TDC for No. 1

Tighten: exhaust valve rocker arm bolts 1, 2, 7, and 8 to 30 Nm (22 ft lbs)

Tighten: intake valve rocker arm bolts 1, 3, 4, and 5 to same torque setting.

Rotate crankshaft 360 degrees

Tighten: Exhaust ........3, 4, 5, and 6

Tighten: Intake..........2, 6, 7, and 8

Nov 12, 2023 | 10:00 AM

vito02

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From: SW CO

Quote:

Originally Posted by vettenuts

Yes, should be a TDC. It's for rocker tightening sequence later when you are re-assembling the valve train. I would set it and mark your damper with a dab of paint.

Yes, I think its wise to verify TDC whenever the opportunity presents.

Nov 12, 2023 | 01:07 PM

grinder11

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Though it's probably best to have as little tension as possible on the rocker when tightening the mounting bolt, I have never had a problem with stripping threads on the AFR 225 cathedral heads I once had, or on the current LS7 heads I'm now using on my LS7 C5. NEVER start the bolts with a power tool. I've always started them by hand, and used just a good old ratchet. My opinion.....