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| | | | Joined: Feb 2010 Posts: 41 Wrench Fetcher | | Wrench Fetcher Joined: Feb 2010 Posts: 41 | Snow here has kept me from crawling around my, "new," 1948 6400 2-ton's engine looking for casting numbers. However, I do have the number behind the distributor which is: 55F1017N. I've spent the morning looking around the Stovebolt archives, etc., and one list suggests that if my number was F55, I'd have a 1955 235. So what's my number mean? It would be nice to find that this truck has a replacement 235 full pressure engine. No idea of it's condition yet; just trucked it home right before snow began.
Am I gaining much by this number?
Happy Thanksgiving,
Dennis | | | | | Joined: Dec 2005 Posts: 2,557 'Bolter | | 'Bolter Joined: Dec 2005 Posts: 2,557 | What are the casting numbers on the block near the starter ?
1951 3100 Chevrolet1951 Chevrolet Suburban CarryallImage"A house is built with boards and beams. A home is built with love and dreams." "Look deep before you leap !!!" / "Everything is Everything" "If I say a mouse can pull a house, hitch him up"
| | | | | Joined: Aug 2000 Posts: 346 Shop Shark | | Shop Shark Joined: Aug 2000 Posts: 346 | Looking at an original 1959 Chevrolet parts manual I found the following note regarding engine serial numbers.
"After October 1, 1956, past model service engines will show the latest year of application immediately preceding the source letter."
The source letter = 'F' means it was built in Flint, 'T' = Tonawanda
In 1954-56 serial numbers were a straight numeric serial number followed by a suffix like these used to indicate 261 engines:
1954 5000 Series F54Q, T54Q
1954 6000 Series F54N, T54N
1955 5000 1st Series F55Q or F54Q55
1955 6000 1st Series F55N or F54N55
1955 6000 2nd Series F255N, T255N
1956 6000 Series F56TA or F56TD
The book doesn't give any further information on the form of serial number that you have (like what the 'N' means).
Last edited by OlBlue; 11/26/2010 9:00 PM.
'38 Chevy 1-1/2 ton
'49 Chevy 1/2 ton
'54 Chevy 6400 2 ton
'55.2 GMC 3/4 ton
'56 GMC 1-ton
No Room Left in Shop
| | | | | Joined: Feb 2010 Posts: 41 Wrench Fetcher | | Wrench Fetcher Joined: Feb 2010 Posts: 41 | Thank you both. I'd have given the block number in my first post had I been able to get to it to read it. I just came in from brushing snow off the truck and taking my camera. (Just got truck home and have yet to get it inside-but even with snow, it's very dry here)
If I can attach a photo properly here, this should help. After spending all last evening reading everything I could find on line, today I see two, what appears to me to be, "captains bars," on the block. I had begun to doubt my reading the engine number correctly, but photo also shows the, "55F."
Questions: do captain's bars ALWAYS indicate a 261 engine? (desirable engine I understand)
From last night's reading, I understand that if an engine has a rocker cover held down with four screws at the gasket flange, it is ALWAYS a high-pressure, post-1954, 235, (or 261?). (Or could it only mean it's a late model head?)
Finally, has my engine number created a new mystery to 235 experts? At this point, I'm thinking that I got lucky and got a 261.
Well, I can't see any way to post a photo. And I don't have a flicker page, etc. My photo showed two, short, vetical bars cast into the block just above the starter. It also confirmed engine number 55F..etc.
Dennis | | |
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