Aging an engine by crankcase numbers.

Identification of case numbers and cylinder heads
Speeding Big Twin
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Re: Aging an engine by crankcase numbers.

#31

Post by Speeding Big Twin »

Jerry, I have photos of M8 on BT trans lids, BT trans cases, BT starter covers, Pan left cases and Pan R-H cases.

I haven’t yet seen M9 on BT trans cases or Pan crankcases. I have photos of M9 on Pan front heads and 12 9 (Dec 49) on Pan rear heads, Pan left cases and Pan R-H cases.

I don’t know if there’ll be M9, or even I9, on a BT trans lid cast in 1949. I have A9, B9 and C9 but they may not have gone much beyond that due to the intro of lids with casting number 33–49.

I haven’t seen I9 yet on a 45” left case cast in 1949.

On 121-41 45” trans cases I have M8 but no I8 yet. Still looking for M9 and I9 on these.
Eric
Last edited by Speeding Big Twin on Thu Jan 05, 2017 1:51 pm, edited 1 time in total.
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Re: Aging an engine by crankcase numbers.

#32

Post by Speeding Big Twin »

old man emu wrote:Would it be a useful if we posted the casting date code and corresponding crankcase numbers and engine numbers so some documentation could be created for researchers?

OME
Do you mean DCs etc from BTs?
Eric
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Re: Aging an engine by crankcase numbers.

#33

Post by old man emu »

My interest is in WLAs, so I haven't looked at anything about BTs, but publishing both would be useful.

Did you see my PM regarding flywheel casting dates?

OME
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Re: Aging an engine by crankcase numbers.

#34

Post by Speeding Big Twin »

Yes I saw the PM re flywheel DCs and it will be interesting to see how they relate to numbering info on your left case.

You’re asking would it be useful if we posted DCs, corresponding BNs and engine numbers? Isn’t that what I did above for 45s? 8)
Eric
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Re: Aging an engine by crankcase numbers.

#35

Post by old man emu »

Speeding Big Twin wrote:You’re asking would it be useful if we posted DCs, corresponding BNs and engine numbers? Isn’t that what I did above for 45s? 8)
Eric
I didn't mean just you. I meant that if members of this forum could supply that information it would widen the database and make for better analysis.

OME
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Re: Aging an engine by crankcase numbers.

#36

Post by Bigincher »

Eric is the only person I know of that is doing this kind of extensive in-depth research. We should be thankful he is willing to share the results with us.
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Re: Aging an engine by crankcase numbers.

#37

Post by Pascal »

Although nowhere near Eric's lists..almost all the VINs on the Yahoo list with a DC are my contributions.
I like this list to be as complete and accurate that's why I'm updating it on a regular basis.
Originally just for the 42WLA..there are also XAs, 41WLAs, WLDs and BTs listed.
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Re: Aging an engine by crankcase numbers.

#38

Post by 1950Panhead »

I have photos of M8 on BT trans lids, BT trans cases, BT starter covers, Pan left cases and Pan R-H cases.
1948 - Pan cases, BT tranny case, lid, kicker cover.
1949 - Pan front heads.
Is this the complete list of M dated parts ?
I posted a M 14-8 UL cylinder in 2012
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Re: Aging an engine by crankcase numbers.

#39

Post by Speeding Big Twin »

For BT aluminium parts, at this stage yes.

For 45" aluminium pieces, apart from the M9 left case I posted above I have M8 on trans cases as I mentioned earlier:
M8 on Flathead 45 trans case.jpg
M8 on Flathead 45 trans case.jpg (109.7 KiB) Viewed 3686 times
I haven’t yet seen I8, I9 or M9 on a 121-41 case.

In 2012 Palmer told me he had M9 on a 50G but he didn’t say what the part was.

I remember your M 14-8 cylinder. I have other examples of M on cylinders from several years and models: Flatheads, Knuckles and Panheads. And it would have been used on Knucklehead heads too but all these are cast-iron parts so M is expected.
Eric
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Re: Aging an engine by crankcase numbers.

#40

Post by 1950Panhead »

I remember your M 14-8 cylinder. I have other examples of M on cylinders from several years and models: Flatheads, Knuckles and Panheads. And it would have been used on Knucklehead heads too but all these are cast-iron parts so M is expected.
So aluminum foundry only used M in 48 and 49.
Did Mocastco ever use I, you have M photos for all the years ?
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Re: Aging an engine by crankcase numbers.

#41

Post by Speeding Big Twin »

I have examples of M on cylinders from several years, not all. These are 38, 43, 46–47, 50–52, 54, 57–59 and 61. And maybe on a 68 but it’s hard to be sure.

AFAIK, MCC didn’t use the letter I on cast-iron parts for H-D Flatheads, Knuckles or Pans.
Eric
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Re: Aging an engine by crankcase numbers.

#42

Post by Speeding Big Twin »

While we're on the subject of the letters I and M, some 45” left cases had the letter I in 1953 but two characters were used for the year:
1953 casting.jpg
1953 casting.jpg (51.04 KiB) Viewed 3658 times
1953 Flathead casting.jpg
1953 Flathead casting.jpg (72.2 KiB) Viewed 3658 times
Apart from I53, other photos in my collection show B51, F51, G51, L51, E52, J52, K52, A53, E53, J53, L53 and B54 on 45” left cases. No photos yet of I for 51–52. No M yet for 51–53. For 1954 there probably won’t be I or M because as early as July 54 the DC had no letters and had become a numbers-only format: 7 4. BTW, 45” left cases with DC 7 4 were around for some time and you’ll even find some with authentic serial numbers as late as 1957 models.

Trans cases cast in 1951–53 for 45s had the same DC format as 45” left cases and examples so far are A51, B51, D51, E51, K51, L51, H52, J52, L52, A53, B53, E53, K53 and L53. These DCs are all under the filler spout. No pictures yet of I or M for 51-later. At some stage the trans DC changed to a numbers-only format and two numbers were used for the year. I don’t know exactly when the change occurred but the earliest example I have is 7 58. Also please note that 7 58 is inside the case, not under the filler spout. (The 45” trans DC changed to another numbers-only format at some later point and was moved to the underside of the case.)
Eric
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