willysmjeeps.com

Hello all,
I have searched online and cannot seem to find what i'm looking for. Is there any way at all to verify for certain that a 1952 M38A1 motor is original other than using the MD serial #? I have been able to locate a number and it starts with FR ######. I am curious if that means anything other than that it may be a rebuilt motor but specific to a M38A1.

Please help me with this confusing info.

Thanks,
Holly

If your engine was installed in your jeep by the Willys/Kaiser factory then the serial number will be MDXXXXX or MDXXXXXX. Once that serial is gone there is no other way to ID any L134 or F134 to a specific chassis application. All the bolt on accessories that make an M38A1 engine can be bolted on a CJ5 or CJ3B or Willys Pickup F134.

If the engine is a factory supplied brand new replacement engine purchased by the Army then it will have a Replacement engine serial number like RMDXXXXX or RMDXXXXXX.

Your FRXXXXX could have came in any Willys/Kaiser built F134 application chassis. The FR is not a standard Willys/Kaiser engine serial prefix.