1939 Pontiac Silver streak head tightening sequence

[openslather]

Hi guys it’s my first post here, and I’m inquiring about about the torque specs and tightening sequence on the head of my Pontiac Silver Streak inline six 223ci. Any help would be greatly appreciated. Thank you.

[Bloo]

Welcome! I have seen this somewhere, but cannot find it right now. That is pretty far back in years for torque wrenches. You may just have to pick a slightly newer Pontiac to get a good guess for the torque spec. I know I have seen the tightening pattern though.

 

EDIT: 60 FT/LB, diagram 174. https://drivcat.com/livedocs/99999.pdf

 

Edited April 24, 2021 by Bloo (see edit history)

[openslather]

Thanks for your reply Bloo. I’ve only just bought the Pontiac and want to try do things the right way. I think 60 FT/LB is correct and the same for both the 6 and 8, it’s the tightening pattern that I can’t find out about, I’ve searched the net high and low to no avail. Not a major problem, I’ll get there. 

[Bloo]

Try Page 65 of the PDF I linked in my post above. Diagram 174. Great to see another Pontiac in here.

 

Edited April 24, 2021 by Bloo (see edit history)

[openslather]

Done. Thanks again. See if I can get it out to get it up to normal running temp and retighten the head to spec.

The old beast (original flat 6) did 560 miles (just over 900 kms) in 2 days to drive it home from South Australia to Victoria here in Australia. No problems. 

[Oldtech]

If you don't have a diagram always start in the center and work evenly out to the ends. Dont tighten one to spec when others are loose,  do it in about 3 stages.  Works on anything.

[Graham Man]

This one should be close, at least you can see the pattern.  On my Graham the only hole that is the correct size is the #1 bolt, all the rest are clearance holes.