RMC block date

[Harleygaz]

Hi. I have an 804380 casting RMC block to go in my M38. The block has 12 31 on the lower left side where the green book shows the date would be but mine also has a cast letter D next to those numbers. Is there any record of Willys adding a year mark on the 804380 blocks when they came into service? If so what year would the D be? Could it be the 4th year of production i.e. 1956?

[RonD2]

Hi Gary,
Is there a serial number on the block?

[Harleygaz]

Serial number RMC106676.

[RonD2]

Hi Gary,
No help, but I have RMC104057 as a spare that I'll eventually get around to rebuilding.

I came across this post from earlier this year. Not sure the answer has changed since then? Maybe the Army was still buying RMC serialized L-head motors in 1956, some 4 years after M38 production ended? From what I gather from Wes and others, the M-series production (contract) records weren't archived anywhere near like the MB/GPW history that was saved from WW2. Most if not all records were destroyed. No way to ever know for sure as far as I can tell. Maybe a field trip to the lowest basement at the Library of Congress would yield a clue.

http://willysmjeeps.com/v2/modules.php? ... hlight=rmc

I've often wondered (for example) using your serial number, if the Army actually bought more than 96,676 motors? One for every M38 off the assembly line, plus spares, and including generators, welders, and maybe a few MB/GPW's still in service? Sounds like an awful lot of motors to me. But our Uncle Sam has a long history of going overboard in the spare parts department. Color me thankful for all the NOS M38 parts still in cosmoline available today!

Just my 2 cents. Good luck!

[wesk]

Gary,

Often an assembly date can be found on the lower face of the block where it mates wit the oil pan.

[Harleygaz]

Hi Wes. Yes, I read about that but I can find nothing on the block where the oil pan fits at all. I’m wondering if post MC production for M38s the RMC blocks were processed differently.