Postwar Lionel 2346 versus 2359

Exactly identical other than the number. Anyone's guess why different #'s, probably because they were made 3 years apart and Lionel didn't want to reuse the same number for book keeping and accounting purposes.

I think O verses O27.    My guess 2346 is O, and 2359 is O27. 

You could ask the same question about other GP7/9 engines of the period, Wabash and C&O for example,

One could be for Lionel, another for a train set for say Sears?

They are both identical in appearance, but were issued in 1961 in a set, then reintroduced again in 1965-66 in another set. A quick check from Olsen's library only lists part numbers and the cab #'s are 2346-2 and 2359-2.  Someone who owns either or both, could take the body off, and check for a mold number inside.  It would be interesting if a 2359 cab had a 2346 mold number, or vice versa with a 2346 has a 2359 mold number.  

It does seem odd for what appears to be an identical body, to have a different cab number stamped, unless it was to differentiate what year it belongs to!!

An example with mold numbers compared to number stamp is the S-2 turbines (671/681/682/2020).  Every shell is a 671-3 shell, and the number stamped is the only difference as far as the number shown in repair manuals.  There are modifications to the original casting, "E unit slot, linkage boss", but all of these shells are marked 671-3 inside.

You could ask the same question about other GP7/9 engines of the period, Wabash and C&O for example,

The Wabash and C&O Geeps, made in two different numbers have different features:

2337 Wabash - non operating couplers
2339 Wabash - operating couplers.

2347 C&O - horn
2365 C&O - no horn, or fuel tank (battery cover)

 Someone who owns either or both, could take the body off, and check for a mold number inside.  It would be interesting if a 2359 cab had a 2346 mold number, or vice versa with a 2346 has a 2359 mold number.  

Lionel didn't mark the insides of their finished shells with a part number, such as 2346-2. Most of the shells have a mold number that did not change. Usually it would be based on the first use of the mold.  In 1955, when the Geeps were introduced, they made three models, the 2028, 2328, and 2338. Since many Geep parts carry a 2328 part number, I am going to guess that the mold number of a Geep shell is 2328-3. I don't have a shell handy to check.

I think maybe Moed321 hit the answer:

2359 came in a Super "O" set
2346 came in an  "O" set

Lionel did offer the same engines with different numbers when they were designated "O", "027" or "Super O"

Only problem with that theorem is both engines were offered for separate sale. 

The only differentiation of "0" and "Super 0" is the track supplied in a particular set.  All of the 2346 and 2359 locos are considered 0.  Not for 027.  My original point was the mold number under the shell, and the reference to part number is what you find when you look at a Service Manual.  I know that not all Postwar shells had mold numbers, but it would be interesting of someone who owned either of them, to see if there was a mold number.  My reference to the numbers listed in Service manuals, is merely the number that Lionel used, to specify how it was stamped for the number.  (Also the paint schemes, and road names)

My guess that if there is a mold number inside the shell, it should be 2359-something, as the 2359 was made first.  If you look in Service manuals, of the various locos that share the same basic casting, GP-7, GP-9, GG-1's etc., the basic assembly starts with one mold, painted a specific color, and stamped with a certain number, but would all originate with ONE specific mold, for the very first issue of that style.  The group of 2328, 2337, 2338, 2339, 2348 and 2028 are all the same BLANK shell before paint, number, etc..  The service manual lists the cab assemblies 2028-2, 2328-2, 2337-2, 2339-2, 2348-5.  Those numbers represent Pennsy, Burlington, Wabash, etc. trim, but the basic body should have one common number molded inside the shell.

I had a Modern era Christmas Geep cab handy. The postwar mold number, #2328-5  was still there when this shell was molded.

There were modifications to the mold, including some new markings in a different location under the roof:

 "Lionel"
"Chesterfield MI 48051-2493"
"Made in U.S.A."

C W Burfle posted:

I think maybe Moed321 hit the answer:

2359 came in a Super "O" set
2346 came in an  "O" set

Lionel did offer the same engines with different numbers when they were designated "O", "027" or "Super O"

I don’t know the answer but I don’t think that is it.  It’s true that with very few exceptions during the post-war period, Lionel used a different cab number on the same engine type when cataloged in an O27 set vs. in an O or Super O Set.  But it appears that rule did not apply to O vs. Super O sets.  Just look at the 1957 and 1958 catalogs as there are 5 different engines that headed Super O sets in those two years that had the same number as when they previously headed O sets.  Those engines are 646, 665, 736, 2331 & 2360.

The Lionel Postwar Trains on-line reference library says “The 2359 Boston & Maine GP9 diesel is almost identical to the 2346 Boston & Main GP9 produced in the mid 1960's.” but they don’t say what that difference is.  The key is finding out what is not identical.  Surely someone on this Forum has one of each and can enlighten us.

Bill