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fastback4
06-05-2010, 07:22 AM
1997 3100 Monte. 41 ft. lb. doesn't seem like very much torque for a head bolt, but adding 90 degree's more to the bolt on the second pass seems like a lot. So whats the final torque? Do you mark the head bolt, call that 0 degrees, and turn 90 more degrees from that point?............Tom

geldartb
06-05-2010, 07:43 AM
off on your numbers a bit but here are the correct specs.

Tighten the NEW cylinder head bolts to 60 Nm (44 lb ft) in the order shown. Use the J 36660-A torque angle meter in order to rotate the cylinder head bolts an additional 95 degrees .

fastback4
06-05-2010, 08:55 AM
Here's what this site's home page under engine specifications has for bolt torque sequence and foot pounds applied.
First Pass 55n 41ft.
Final Pass Add 90 degrees

*Manifold Side*
6 2 3 7
Notice the circular torque sequence versus your staggered sequence?
5 1 4 8
* Outer Side *

geldartb
06-05-2010, 10:31 AM
the torque sequence was revised so depending on when that was written on here it most likely was written before the specs were revised.

date on this article for the revision say 08 so most likely the stuff on this site was written before that.

INFORMATION

Bulletin No.: 02-06-01-003B

Date: April 15, 2008
Subject:
Revised Cylinder Head Bolt Torque Specification and Tightening Sequence

Models:
1994-1998 Buick Skylark
1994-2002 Buick Century, Regal
2002 Buick Rendezvous
1994-1996 Chevrolet Beretta, Corsica, Lumina APV
1994-2000 Chevrolet Camaro, Lumina
1994-2002 Chevrolet Monte Carlo
1997-2002 Chevrolet Malibu, Venture
2000-2002 Chevrolet Impala
1993-1996 Oldsmobile Ciera
1993-1997 Oldsmobile Cutlass Supreme
1994-2002 Oldsmobile Silhouette
1996-1999 Oldsmobile Cutlass
1998 Oldsmobile Achieva
1999-2002 Oldsmobile Alero
1994-2000 Pontiac Firebird, TransSport
1994-2002 Pontiac Grand Am, Grand Prix
1999-2002 Pontiac Montana
2001-2002 Pontiac Aztek

with 3.1L or 3.4L Engine (VINs J, E - RPOs LG8, LA)

Supercede:

This bulletin is being revised to include a Notice advising that the cylinder head bolts are NOT to be re-used. Please discard Corporate Bulletin Number 02-06-01-003A (Section 06 - Engine).
Notice: This component uses torque-to-yield bolts. When servicing this component do not re-use the bolts. New torque-to-yield bolts must be installed. Re-using used torque-to-yield bolts will not provide proper bolt torque and clamp load. Failure to install NEW torque-to-yield bolts may lead to engine damage.

The cylinder head bolt torque and tightening sequence have been revised. This revision has been made in the SI. If you are using a paper version of this Service Manual please make a reference to this bulletin on the affected page.

The revised specification is as follows:
this and the specs i posted were pulled from my alldata subscription

fastback4
06-05-2010, 11:27 AM
Thanks........Tom
By the way. I used your new numbers for torquing the heads + 95 deg. I used a dial foot pound torque wrench and after adding the 90 degrees, final torque was at around 97 foot pounds...This number is what i got. Please do not use it for a replacement of actual bolt degreeing.