Help Identifying MB engine

1941 - 1945, MB, GPW Technical questions and discussions, regarding anything related to the WWII jeep.
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jkillelea
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Help Identifying MB engine

Post by jkillelea » Mon Jan 22, 2018 2:10 pm

Hi Guys.
I have MB engine 390112. The casting date on the block is 3-27 and the casting date on the head is 3-23. Anybody have an idea about the DOD or the Willys serial number? It has a recondition tag from the 5th Service Base Shop in Newark, Ohio. The date of the reconditioning is stamped 3 29 45, then overstamped 3 30 45
Thank you so much.


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Re: Help Identifying MB engine

Post by sjalbert » Tue Jan 23, 2018 9:39 am

The engine is from 1944. If you remove the oil pan you'll find the machining date near the rear journal bearing. That date is likely early April 1944. MB Serial numbers in early April were around 320xxx.
Seth
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1944 MB 349858, 20620361
1942 MBT 10968 viewtopic.php?f=18&t=149552
1942 MBT 15799, USA 0217497 viewtopic.php?f=18&t=225199
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Collecting Willys Engine Info. Please send me Engine #, Casting Date & Machining Date if known

jkillelea
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Re: Help Identifying MB engine

Post by jkillelea » Tue Jan 23, 2018 9:43 am

Thanks so much sjalbert!

jkillelea
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Re: Help Identifying MB engine

Post by jkillelea » Tue Jan 23, 2018 11:03 am

Thanks. I know to look on the oil pan surface, but unfortunately, I'm not able to take the pan off at this time.

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Michael O.
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Re: Help Identifying MB engine

Post by Michael O. » Tue Jan 23, 2018 1:36 pm

I bet your machining date is 3-29-44 or 3-30-44.
Michael O’Connell

Too many jeeps…and a Dodge.

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jkillelea
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Re: Help Identifying MB engine

Post by jkillelea » Tue Jan 23, 2018 3:18 pm

OK, so if the casting date is Monday March 27, then would the block be cooled enough two days later to be machined (on Wednesday March 29) as opposed to Thursday March 30? How long does a block take to cool down enough for machining? Would/could a block be machined when it is room temperature, still in the cooling down phase? Is it better to machine a block when it is slightly cool or warm? Just a little curious about metal expansion/contraction in this whole process. March 1944 had Willys delivering lots of jeeps. Maybe they had blocks cool down faster in a cool area of the building so that they could deliver jeeps faster. Didn't they roll a jeep off the assembly line every 90 seconds?
Thanks

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Re: Help Identifying MB engine

Post by sjalbert » Tue Jan 23, 2018 4:07 pm

Shortest I've seen is 3 days between cast & machining. Typical is 5 days. Blocks were not necessarily machined in the order they were cast. Just like tubs weren't used in the order they were received. Hence the reason their is not a definitive correlation between serial number, tub number and engine number for a MB. Fords had the block serial number stamped at the same time as the vehicle serial number so they "match".

Generally blocks that went into a jeep ended up there between 2 & 10 days after machining from the data I've collected.
Seth
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1944 MB 349858, 20620361
1942 MBT 10968 viewtopic.php?f=18&t=149552
1942 MBT 15799, USA 0217497 viewtopic.php?f=18&t=225199
MVPA # 8587
Com / Inst. SMEL
CFII - ASEL
KI5LYB

Collecting Willys Engine Info. Please send me Engine #, Casting Date & Machining Date if known

jkillelea
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Re: Help Identifying MB engine

Post by jkillelea » Tue Jan 23, 2018 4:16 pm

Thanks Seth, Bantamj, and Michael. All this knowledge is much appreciated.
John

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Chuck Lutz
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Re: Help Identifying MB engine

Post by Chuck Lutz » Wed Jan 24, 2018 8:47 am

FYI....GPWs did not have the block number and vehicle serial number stamped at the same time.

The engine was built in Dearborn and stamped with a serial number at that time. Motors were then shipped to any factory needing resupply and when the frame and motor met up on the assembly line, the frame was stamped with the motor number. The data plate was then also stamped with the motor number.

That is how a "matching numbers" GPW came together.
Chuck Lutz

GPW 17963 4/24/42 Chester, PA. USA 20113473 (USA est./Tom W.)
Bantam T3-C 1947

jkillelea
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Re: Help Identifying MB engine

Post by jkillelea » Wed Jan 24, 2018 9:10 am

Thanks Chuck,
Always great to hear your contributions to this site and research.
John


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