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| | | | Joined: Nov 2011 Posts: 196 'Bolter | | 'Bolter Joined: Nov 2011 Posts: 196 | OK- so after all the recent posts I thought I'd better take a look at what my numbers say.
So here is what I have found thus far:
DBA339360 (next to dsitributor) + down to the right of the distributor it looks like just two digits: 20
839401 (on top by valves) + CONY12
Little confused here.
Thanks! | | | | | Joined: Jul 2005 Posts: 581 Shop Shark | | Shop Shark Joined: Jul 2005 Posts: 581 | Engine Serial# : . D=1946 . B=Reg. Prod. 1/2 ton . A=Flint MI . #'s=Sequence Head # was used thru the 40's. Standard 216. Between the exhaust valve of 4 & 5 there is another number like "L26 6". The L is the month, 26 the day, and 6 the year; so Nov. 26th, 1946.
Last edited by 641Workmaster; 01/03/2012 3:44 PM.
| | | | | Joined: Nov 2011 Posts: 196 'Bolter | | 'Bolter Joined: Nov 2011 Posts: 196 | Great. Thank you. I will look for the other numbers.
What does the "conv12" or "cony12" stand for?
I saw it noted in one of the previous posts, but no explanation. | | | | | Joined: Sep 2001 Posts: 29,269 Bubba - Curmudgeon | | Bubba - Curmudgeon Joined: Sep 2001 Posts: 29,269 |
It supposedly refers to the assembly line CONVeyer number.
| | | | | Joined: Nov 2011 Posts: 196 'Bolter | | 'Bolter Joined: Nov 2011 Posts: 196 | Bingo : J56 October, 5th 1946! Thanks again, now I just have to get it to turn over!  Andy | | | | | Joined: Apr 2005 Posts: 507 Shop Shark | | Shop Shark Joined: Apr 2005 Posts: 507 | Remember the letter I and O are not used to indicate the month of the casting.
Last edited by 41Chevy; 01/03/2012 3:13 AM.
"If it ain't Steel it ain't Real" "Earth the insane aslyum for the rest of the Universe" 41 1/2-ton, a work in progress 68 Shortbed stepside 327/325hp/700R4
| | | | | Joined: Nov 2011 Posts: 196 'Bolter | | 'Bolter Joined: Nov 2011 Posts: 196 | Ohh....
Didn't know that!!!
So J = September!!
Thank you! | | | | | Joined: Nov 2011 Posts: 196 'Bolter | | 'Bolter Joined: Nov 2011 Posts: 196 | On second thought the skipping of the "I" and the "O" certainly contradicts the link Tim psoted about the head and date casting codes earlier in this thread!!?! | | | | | Joined: Sep 2001 Posts: 29,269 Bubba - Curmudgeon | | Bubba - Curmudgeon Joined: Sep 2001 Posts: 29,269 |
Andy,
I do not know about the I/1 and O/0 being skipped on USA Chevrolet trucks. But, it is possible.
I do not have GM documentation on date casting codes. I'd be interested in learning that my interpretation is wrong.
| | | | | Joined: Jan 2001 Posts: 5,337 'Bolter | | 'Bolter Joined: Jan 2001 Posts: 5,337 | I do not think Tim is wrong in this case.
See the USA in your vintage Chevrolet! My Blog | | | | | Joined: Apr 2005 Posts: 507 Shop Shark | | Shop Shark Joined: Apr 2005 Posts: 507 | only the letters I and O are not used to prevent confusion with the numbers 1 and 0.
"If it ain't Steel it ain't Real" "Earth the insane aslyum for the rest of the Universe" 41 1/2-ton, a work in progress 68 Shortbed stepside 327/325hp/700R4
| | | | | Joined: Jan 2001 Posts: 5,337 'Bolter | | 'Bolter Joined: Jan 2001 Posts: 5,337 | I have several problems with that statement.
First there is no need to use "O" as "L" is the 12th letter, M if L is not used.
Second I am pretty sure I have seen an "I" used.
This would also mean that M was used and I do not remembering ever seeing that.
See the USA in your vintage Chevrolet! My Blog | | | | | Joined: Sep 2001 Posts: 29,269 Bubba - Curmudgeon | | Bubba - Curmudgeon Joined: Sep 2001 Posts: 29,269 | Dave, Thank you for your post. It confirms what I had thought was the case on blocks/heads but I have no supporting documentation. 41Chevy's comment about Os and Is tweaked my unreliable memory regarding that practice - I think I now remember where I read that Is were not used in AC Delco Remy (Division of GM) date codes: example 1 (for Is); example 2 (for Is); and, example 3. | | | | | Joined: Apr 2006 Posts: 506 Shop Shark | | Shop Shark Joined: Apr 2006 Posts: 506 | Good point Dave for month "O"
Ditto, A thru L.
The letter "I" was not used in the vehicle serial number, year.
Example,
1950 = "H"
1951 = "J"
-Tom
1950 Chevy 3100 w/ 1956 235
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