2003 GMC Yukon Adjusting Rockers/valves

DEREKROSENBERGER

MEMBER
2003 GMC YUKON
6.0L
V8
AWD
AUTOMATIC
216,000 MILES

Just replaced the Head Gaskets in my Yukon. When following my Hanes Manual it says to locate TDC for Cylinder number one then torque Intake valves on 1, 3, 4, 5 and exhaust valves on 1, 2, 7, 8 to 22 ft/lbs. After doing this I am suppose to rotate the crank 360 degrees. At this point I was unable to rotate the crank because it came to an abrupt stop. I loosened all the valves and I am able to rotate again. My engine does not have timing marks on it so that I can correctly find TDC. I made sure that I was on the compression stroke and tried the screwdriver in the spark plug hole trick (not confident in this method) to get to the TDC. Is there another method for finding TDC? Do I have to have it exactly at TDC with the self adjusting valves? Is there something I missed?

3 Replies

HMAC300

MECHANIC
48,601 POSTS

See pic, you can also use your finger in plug holeand if you tighten rocker down and valve starts to move down then it's in wrong position. Make sure rocker ar m pivot support is installed and that pushrods are centered on valve lifters. Not on edge.

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