Engine information

willysmbnut · Post by **willysmbnut** » Mon Jul 21, 2008 6:08 am

My 1943 Willys MB has an engine of a later date. The engine number is RMD 116440; casting number 908756. I would like to know more about this engine (when was it built; construction details; can I use modern multigrade oil; is it advisable to use a lead replacement additive).
Can anyone help?
Thanks,
Henk Strijker.

Post by **wesk** » Mon Jul 21, 2008 7:12 am

That is a Willys factory replacement M38A1 engine. It is an F134 having the four exhaust valves in the block like an L134 but having the four intake valves in the head like an overhead valve engine and is called an F134. It is not the correct engine for your MB. It is several inches taller than the L134 that belongs in your MB. This usually requires a hole in the hodd for the carb or lowering of the driveline in the chassis. That casting was used from the mid 1950's and up.

Any quality oil will work. Lead supplements are not necessary in these old low compression, long stroke, low RPM engines. They will handle todays unleaded fuel just fine. If ran hard or prolonged highway use at 50 MPH or higher then the stelite exhaust valves and hardened valve seats should be used but should already be there..

willysmbnut · Post by **willysmbnut** » Tue Jul 22, 2008 3:29 pm

Hello Wes,

Thank you very much for answering my questions . It's a pity the engine in my jeep is not an original, but, on the other hand, maybe the quality is better. Anyway, I will keep it in, for the time being.

Searching on the Internet I found a message at G503 Forum stating that 908756 blocks were L134 blocks, almost identical to 804380 blocks (mainly differing by hardened valve seats). Could you comment on that? Were 804380 blocks really F134 blocks?

One last question, if I may: Is it possible to find a more precise production date of the engine in my jeep (RMD 116440)?

Thanks again for your help,

Henk Strijker.

Post by **wesk** » Tue Jul 22, 2008 6:13 pm

MDXXXXXX is the serial number of a M38A1 and M170 F134 engine.
RMDXXXXXX is the serial number of a M38A1 and M170 factory replacement new F134 engine.

Perhaps you have fed me the wrong serial number prefix from your block?

I actually ignored your casting number above. But now that you are emphasizing your casting number then the serial number you gave us is no where near correct for any L134 block.

willysmbnut · Post by **willysmbnut** » Wed Jul 23, 2008 11:56 am

I double-checked the prefix. It is definitely RMD. If this does not match the casting number I guess the casting number must be right and someone must have put the wrong prefix to the engine number.
If this should be the case (casting number 908756 is correct), would that mean that it is an L134 block?

Post by **wesk** » Wed Jul 23, 2008 9:39 pm

Yes a 908756 casting is an L134 engine (all valves are located in the block).

908756

Here's a new in the crate 1962 MDXXXXXX series F134 engine.

Post by **Ryan_Miller** » Wed Jul 23, 2008 9:53 pm

Henk,

Are you sure it is RMD and not RMC?

willysmbnut · Post by **willysmbnut** » Thu Jul 24, 2008 4:19 am

Hello Wes and Ryan,

Thanks for the pictures Wes. Yes Ryan, I am absolutely sure I gave the right numbers. To prove it I have taken some pictures just now but I don't know how to attach them to this message. Could you explain how to do this, or shall I attach them to a private e-mail to you?
I guess I must have a remarkable engine in my jeep! Please let me know what you think of it.

Thanks,

Henk.

Post by **Ryan_Miller** » Thu Jul 24, 2008 2:41 pm

Hey,

To post a photo you have to upload the photo to a photo sharing website. Then on the post reply box in the upper right there is an icon "Img" click that then past in the URL and then click the "Img" icon again and that is it.

RMC engines were often used as replacement engines and for generators.

When a block is rebuilt and decked, the numbers get removed from the water pump boss. They have to be restamped and that is what could have happened.

Pictures would be great.

willysmbnut · Post by **willysmbnut** » Thu Jul 24, 2008 3:23 pm

Hello Ryan,

I don't know how to use a photo sharing website, so I sent the pictures to your private e-mail address.

Henk Strijker.

north-shore · Post by **north-shore** » Fri Jul 25, 2008 2:56 am

Hi

http://imageshack.us/?x=my5&myref=http: ... highlight=

and after copie the link in you message

Post by **Ryan_Miller** » Fri Jul 25, 2008 1:12 pm

Hey,

I checked my email and have not recieved the photos yet.

Make sure you click on the email icon at the bottom of this posting.

The photo sharing websites are easy. You can also request a phot album on this site for use here.

Ryan

willysmbnut · Post by **willysmbnut** » Fri Jul 25, 2008 3:49 pm

Hello Ryan,

I'll try your e-mail again.

Henk.

willysmbnut · Post by **willysmbnut** » Mon Jul 28, 2008 6:56 am

Hello Ryan,

I answered your e-mail on Saturday 26th, and attached the engine pictures. Did you receive that? If not there must be something the matter with your e-mail, because later I sent pictures by e-mail to someone else that were received all right.

Henk.

Post by **wesk** » Mon Jul 28, 2008 1:40 pm

My guess is an engine shop had your block in the same time they had a F134 for a M38A1 in and stamped the rebuilt M38A1 engine's serial on your block by mistake. That means there may well be a RMD engine owner out there with a Jxxxxxx stamped on his serial pad.