308 engine decode

schillazschillaz Posts: 274Expert Adviser
Curious what the stamped number on the raised boss (left top) side of my engine is. The number format is F1XXXX.
I have two engines both starting with F1 and they both appear to be different years.

Casting numbers below the distributor are:
S     2

The other engine with F1xxxx serial #
S    2 

What I have found so far: ;https://hudsonrestoration1948-54.com/HudsonEngineIDCodes1.pdf
308 cu. 1955 532500 A135 CWC
308 cu. 1956 532500 K45 CWC


  • 54coupe54coupe Posts: 331Member
    The K 45 code... the k is the month. November. 4=fourth. 5=1955.
    k 135 is Nov. 13, 1955.
  • schillazschillaz Posts: 274Expert Adviser
    Thanks 54coupe,

    So that being said I will visit with Ken Cates and see if we can modify that document. I assume it should read K46 if its a 1956 example in the document.

    I'm still curious of the F1 serial number. Is that just in 1955 they used F1XXXX?

    Reason i'm am asking is both these 1955 engines are in 53 and 51 cars. One of them has some gray appearing on it and makes me think its a JC Whitney replacement engine.
    *or didn't those engines have any serial numbers?

  • GlowplugGlowplug Posts: 1,962Expert Adviser
    Dan as you already know, I am working the "facts" with the chart author and will react accordingly.  Thanks for providing input for the website.  As far as replacement engines go... Factory replacement engines were not painted. The blue engines are generally know as the "crate engines or left over engines" that were made available near the end of the HUDSON big 6 usage years.  If the engine was installed in an earlier vehicle the relieving vehicle ID was to be stamped onto the replacement engine.  Sometimes this was not done.  I have a 56 308 with a 53 serial number stamped into the engine boss.  This engine was sourced from a 1953 Hornet.  So, as some say... it is what it is....  Will update as the facts are sorted out.

  • GlowplugGlowplug Posts: 1,962Expert Adviser
    Dan you can go to my website and see the updates that have been made to the chart after a review by the keeper of the data that is contained within them.  The information on the page reflects the date known to the data keeper.  The revision date shown is from the original information provided and it reflects what should have been posted.  Ken Cates
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