1930 Pontiac Big Six Torque Specs

[Ken Tereck]

I have a service manual for the 1930 Pontiac and nowhere in the engine or specifications does it provide the torque specifications for the critical fasteners such as the main bearings, conn rods, cylinder head, flywheel, etc. I have also searched the web for these as well with no luck.

I would greatly appreciate anyone providing this information. 

Thank you in advance

[Bloo]

This is because torque wrenches were not a thing yet in typical garages in 1930. "Tight" or "Snug" is probably what the book says. I have a 1936 Pontiac, and there are no specs for it either. In some cases you can look at newer engines of the same engine family. That worked for me, but won't work for you as the split-head six did not remain in production long enough.

 

There are tables of standard torques for standard bolt and thread sizes, and that is probably the best you can do. You should assume grade 2 on the charts unless you know the bolts and threads are better than that, as bolt quality took quite a leap in WW2, and prewar fasteners may be rather soft.

 

There are other split-head six owners in this forum, so you may get better answers that this as the thread progresses. If not, you might try posting in one of the Pontiac sections.

 

[keiser31]

4 hours ago, Ken Tereck said:

I have a service manual for the 1930 Pontiac and nowhere in the engine or specifications does it provide the torque specifications for the critical fasteners such as the main bearings, conn rods, cylinder head, flywheel, etc. I have also searched the web for these as well with no luck.

I would greatly appreciate anyone providing this information. 

Thank you in advance

This might help....

[Bloo]

Wow, I have that chart and didn't realize it went back to 1926! 👍

 

The head torque sequence diagram shown would only apply back to 1935 however, as earlier Pontiac sixes were a different engine family and had 2 heads.

[32Pontiac6]

The Oakland Service manual does not specify a tightening sequence or recommended torque for the '30 Pontiac 6.  They do provide some instruction on the V-8.  My process is to tighten per the sequence shown on the photo.  I torque to 60 ft-lbs.  I progressively torque using the pattern below to 20, 40, then 60 ft lbs.  Another thing is that after you run the car and get it warm I suggest tightening again (and again) until they stay at 60.  I have found after the first run of the car the bolts will rotate maybe 1/8 of a turn to reach torque spec.  No guarantee this is the proper method but it has worked well for me on both a '30 and '32 over the years.  

Hope this helps.

Rob

 

[Ken Tereck]

Thanks for all the information provided. Greatly appreciated