Cylinder Head Tightening Chart 262

48Sed
48Sed Senior Contributor
I came across a Technical Service Bulletin that shows a different chart for tightening the head down than the factory manual chart.
Does anyone know if one is better than the other.
It starts off All Hudson Owners but later talks about the Aluminum head.
I want to use the best chart for a 48 iron head.
Thanks

Comments

  • Lee ODell
    Lee ODell Senior Contributor
    48Sed

    Walt Mordenti uses this pattern to tighten his cylinder heads with success for all 6cyl 48-54 This information come out of Walt's Hudson Tech Tips book Volume 1

    carburetor side
    21 14 6 2 8 12 19
    16 11 4 1 5 10 17
    18 13 9 3 7 15 20
    distributor side


    With 7/16 bolts tighten 40. lbs., then 50, then 65

    With 1/2 bolts tighten 50 ft. lbs., then 65., then 80, then 95. You will notice that the 1/2 bolts or studs require four steps.

    An important part of this job is waiting at least 15 minutes between each step. Once you have started torqueing the cylinder head do not stop until the job is complete(i.e., don't allow any interruptions like answering the phone or talking to friends). .

    After you are done torqueing, run the engine until it is warm (or at least 1/2 hour), then let it sit for 12 hours. Now set your torque wrench to two (2) ft. lbs. above your last setting and re-torque the head
    Any questions contact Walt

    A little more information than you requested but I thought you might like to have it. I recommend getting a copy of both Walts Tec books, they have invaluable information you will not find elsewhere.

    Lee O'Dell





  • Lee ODell
    Lee ODell Senior Contributor
    Correction: Torque pattern for all six cylinder Hudsons
    I missed adding that note under the diagram.

    There is also a torque pattern for all eight cylinder Hudson in Walts Tec book.

    Lee O'Dell
  • 48Sed
    48Sed Senior Contributor
    Thanks Lee
    This now makes 3 different charts for the big 6 so I quess any of them will work.
  • KTRON
    KTRON Member
    edited March 2015
    Ive worked on hundreds of flat head engines, and have never seen a torque sequence so linear/symmetric. I surely would have thought that the order of torque would have been more diagonally opposed from one fastener to the next. This is all good to know, but does the torque value change if you are running a "composite" or "copper" head gasket, and what would be the acceptable "out of flat" range be for the aluminum and cast iron cylinder heads? Judging by length maybe 0.002" on the minor axis and 0.004/0.006" on the major?

    Thanks,
    Chris
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