cj power train in an M38?

[jeeps8]

Have been working on the power train on my M38 and have ran into a few things that are not correct for an M38. The shifter has a screw on shifter ball and no skid plate on the oil pan. There is no MC serial number on the ser. # pad (above the water pump) but there is a 9729 stamped onto the front, on the the water pump face and also on the head. there is also a data tag under the distributor with raised #'s of 3557598, the rest is painted over. There are only 2 freeze plugs on that side.Is this enough info to tell if it is a CJ motor, or is there a way to tell without a serial # ( or is the # somewhere else on the block if it is a CJ)?
The motor was painted years ago, but all the accessories did have green paint on them. Are there other things i should look out besides the oil pan and shifter in order to make it correct?
Thnx.

[jam51m38cdn]

Check out this site, WW2Jeeps.com It has a good visual reference of engine blocks and heads. Jim

[jeeps8]

ran some looks of the website, didn't even see the markings on my head. maybe that was a replacement.

6/48 casting date maybe

Late style block though

should of included these in the first post i guess

[jam51m38cdn]

You must have missed something on the website, the head and block are m-38 Jim

[wesk]

The 800376 head casting number is correct for a M38 however it must have the raised boss on the front end drilled and tapped for the water pump bypass hose fitting. If not is a civvy head.

The 804380 block casting appears in late spring 1952 and was used in many jeep products besides the M38. The only way to tell in what chassis that engine was originally mounted by the factory is by the serial number above the water pump. For that engine to be an originally installed M38 engine it must have a MCXXXXX serial number. No other number will work for an original Willys installed engine in an M38. A factory new replacement engine installed in the field by the military would have the serial RMCXXXXX. Without the MC or RMC serial your block has no way to prove it was an original M38 engine. The lack of a oil pan skid plate also enforces the opinion the engine is a civvy engine.

The plate below the distributor is a rebuild plate and the number is likely a work order number.

[jeeps8]

no tapped hole. also an EM along with the 9279 on the water pump mounting face.

It looks like the pad was machined, probably 20 years ago by the engine shop. It's probably wishful thinking but there does appear to be a real faint 8 still slightly there. Any cops with any ideas to see if there was a serial number stamped there?
I found an oil pan with a skid plate and with have to put in a bypass fitting. Either way, it's an M38 motor now. Any other details i should look for and possibly change to get the details right?

[wesk]

Without the visible MCXXXXX on that pad above the water pump you have a generic 804380 block. You are welcome to fake it but the bottom line is it can never be established what chassis or power unit that engine was originally installed in. If you want a factory correct show M38 you'll have to find a block in the right MCXXXXX serial range. To make the bare block you have look like an M38 block just paint it OD 2430. The only difference between an M38 bare block and a CJ bare block is the serial number and the paint. Then to complete the dillusion just add all the appropriate accessories listed in the M38 ORD 9.

[jeeps8]

I guess sometimes you don't always hear what you want to hear on here. Like your rebuilt motor isn't correct. But if your gonna do it right, do it right the first time. So my question is: is there a certain serial number range or does it just have to be a MC or RMC number? I saw on the data base the number range was pretty wide.

Is there anybody out there close to St. Louis that might be willing to trade for a decent running correct motor for this one?

P.S. Thnx for setting me straight Wes.

[wesk]

Unless you are doing a show ready factory class resto the missing serial number has no effect on your jeep.

Let's take a look at how the ball can roll during an M38's 60 year life span.

1-New M38

2-In 1957 the engine gets tired at Fort Amos & Andy.

3-Motor pool selects a new factory replacement 804380 casting, serial number RMC123456 and installs it. All factory new replacement engines came with the RMC prefix.

4-In 1976 Podunk, KS fire department owns the M38 and has the engine rebuilt. The block gets decked and the serial disappears. The head was cracked and here comes a civvy replacement.

I cannot prove this theory and in all liklyhood no one can disprove this theory. So as I said above if you are not building a factory class trailer queen then press on with what you have.

[jeeps8]

http://www.suzukihayabusa.org/forum/ind ... opic=92921.

Have seen a few more posts asking the same question about the serial numbers. I ran across this during my research. I haven't tried it yet, but plan on it soon. Hope it might help.

[RICKG]

details are a good thing-but theres such a thing as too much
of a good thing. i find that when MY attention to detail overcomes
the reality of what i have to work with im stuck-work stops-
-nada. altho i'm not related to bubba i gotta run with what i got.
the important thing is that we're rescuing a mv and having FUN
DOING IT.

[rgmutchler]

I know this might be a little late but I just ran across this post. Contact your local Police dept. or Sherif's Office or State Police. They should have an acid kit that is used to raise serial numbers that have been ground off guns or other metal things. While they might not do it for you they can give you the info to make or buy your own kit.