Serial Numbers FYI

[Ralph]

It has been asked how the serial numbers on the frame and the serial numbers on the block relate to each other on the same tractor.

My 65 cub Blackie has a Frame #226974
Engine #250917

Difference 23943



My 70 cub Florence Has a Frame #235004
Engine #272742


Difference 37738

[Ron L]

Ralph. I heard it said here that the earlier the Cub, the closer the serial numbers would be..... My '48 Tilly's serial # is 55108. Her engine ser # is 55515 (difference of 407). . So I guess that could hold true........

[Matt Kirsch]

Makes sense. They also used Cub engines for power units, and they were almost certainly pulling them off the same assembly line.

[cowboy]

What I have on my 1964 cub is

frame tag is
223744 J

cast int the block by the dipstick is
251341 R7

on the head
251228 R1

for what its worth difference of 22,484

[Bigdog]

Cowboy, those numbers ending with an R & a number are part numbers, not serial numbers. The engine serial number is here:

[cowboy]

Thanks BigDog

I am sure I would not have found them hiding behind the hyd. lines like that.

Learned me somthing new today

now I have on the frame
223744 J

and on the block
F CUB M 244971

for a grand difference of
21,277

[electromech31]

What can I do if Im missing the tag for the serial number on the frame. I have found the engine serial number.

[Bigdog]

With a missing serial # tag, you will never know your tractor's serial number but by looking at the engine serial number and the casting date codes you can approximate when your tractor was built. The casting codes are located on all of the major castings and it will give you the month and day plus a letter code for the year. There is a chart at this link (thank T.M. Tractor) that will tell you the corresponding year for the letter.
You can check those numbers on all the castings. They should be fairly close but not necessarily the same for the major pieces. Different castings had different inventory lead times. For example, it would not be unusual to have castings from late 48 and early 49 on the same tractor. Anyway, your tractor was probably built within a few weeks to month after those casting dates.

[electromech31]

So my little red tractor is a late 47 to 48. Now I can have a birthday party

[Jim Becker]

OK, here are a few more numbers to try to chew on:

October '54, first Cub built was serial 181650, engine 185035. (Last digit of each number is a semi-guess because the photocopy chopped the edge off.)

The last Cub built in October '54 was 182161. I don't know the engine number of this tractor, but since it was 500+ tractors after the one above, you might guess it was around 185550 or so.

The next Cub after that one was built in November '54. The engine number was 185574, which seems about right. The tractor serial number was 185001.

Serial numbers 182162 through 185000 were skipped. Evidently there was no skip in the engine numbers.

[Lurker Carl]

Here are some more numbers. I am assuming these are the original engines in the tractors because the major castings are very close in date to the engine. Does anyone know whether the engine serial numbers started at 1 or 501?

Cub sn 11772 with Engine sn 12445 = 673 more engines in early 1948
Cub sn 147352 with Engine sn 148779 = 1427 more engines in early 1952
LoBoy sn 15516 with Engine sn 233927 = WRONG ANSWER

The LoBoy is 10th one made in 1962, adding first 1962 Loboy serial number to first 1962 Cub serial number = 235544. That's mighty close, not knowing how many 1962 Cubs came down the assembly line before first LoBoy or other serial number discrepancies. Be aware that there are replacement blocks and power unit blocks that throw the serial numbers off, but the LoBoy line grabbed thousands of blocks as well.

[Jim Becker]

Bud,
The first Farmall Cub built in '62 was 220038 with engine 238885. The first Lo-Boy in '62 was 15506 with engine 238892. Check your engine number again. If 233927 was really 238927, it would look pretty reasonable. By the way, engine 233927 would probably have had a 1960 date code.

Keep in mind that engines were not necessarily used in strict number sequence. As far as that goes, the tractor serial numbers didn't necessarily come off the line strictly in sequence either.

On quite a few models before the Cub, IH kept the engine and tractor numbers in sync. That pretty well forced the engine numbers to start at 501 as well. Even though the Cub numbers weren't kept in sync, I imagine the engines still started at 501.

[Lurker Carl]

The first Farmall Cub built in '62 was 220038 with engine 238885. The first Lo-Boy in '62 was 15506 with engine 238892. Check your engine number again. If 233927 was really 238927, it would look pretty reasonable.

Jim,

I rubbed some chalk on that engine number for better contrast - the real engine number is 238927. That explains why the date codes match!

Thanks,

Carl