Scored Cylinder Sleeves

[rgmutchler]

Another thing to consider is the serial # on your Texas title. I think you said you got the jeep from TX. If so TX MVD uses the engine serial # on the title. Not that some don't slip through but that is the # by TX MVD regs that they use.
So, what # is on your title? Is it the # on the data plate, the # on the patent plate, as assigned VIN or the engine #? If it is the engine # does it match the engine you now have?

I don't think it is hard to change the # on the title if you have to swap engines, at least in TX, Don't know about Florida. But in most states you have to have the vehicle #'s inspected to apply for a new current state title.

[Naugha]

Here is a RMC engine available from a source suggested by Ron in a previous post. Would someone like to critique this L-134 in terms of appropriateness for my M38 / # MC 52408 .... 2/52 ..... over stamped 55 on the dash data plate, which is another oddity I don’t understand.... uh, did they even make M38’s in 1955?

I have also located a MCxxxxxx engine (or two). Like you guys said, you got to ask.... suppliers don’t always list stuff sitting under a tarp in the back room.


https://smd.craigslist.org/pts/d/hughes ... 52680.html

[RonD2]

Don,
Maybe it's just me (computer challenged) but I can't see anything with that link.

I seem to recall that a few M38's were made after the main production ended in July 1952. Foreign military export contract in 1955 maybe? But that doesn't explain the over stamp.

Does your M38 also have the Patent Plate? Do the serial numbers match?

This is a Wes question.....but I bet he tells us it's in the M38 Reference Guide (a.k.a. "the Book"). I'm looking now.....

[RonD2]

Don,
I figured it out. If you remove the [/quote] at the end of the link it'll work.

Hard to tell which motor is which. Does the loose crankshaft belong to the RMC motor? Not having the original (and serviceable) crankshaft and matching main bearing caps means extra special machine shop work to mate them up properly. Generally speaking (and I'm a rookie) they look pretty good M38 to me. It's hard to inspect long distance isn't it? There's nothing like a hot bath and a magnaflux to really get a good look inside her kimono and see if you really really want to lay out the geeters.....

I like not seeing broken studs anywhere on the manifold and head or anywhere else. Makes me think somebody cares. Does anybody do that for scrap metal? The one with the Industrial head has bolts vice studs which makes me wonder proper or not.

[Mike_B]

Ok, I'll jump in here...these are my engines and that's my CraigsList ad.

https://smd.craigslist.org/pts/d/hughes ... 52680.html

I added 9 new pictures today to let Don see more of the RMC block. All of these parts came to me in a buyer takes it all or nothing deal, sort of. I don't have any history on the parts and I can't confirm that the loose crank was originally in this block, but the main caps are bolted in place by whoever took this engine apart.

The Industrial head is bolted to a block with no serial number stamped...this engine is still all together (head to oil pan) and does turn over.

I'll do my best answering any and all questions, but I'm a Jeep rookie also!

Mike B

[RonD2]

Hey Mike,
I thought that was yours.

Looking at the crankshaft photo again I think I see a straight cut gear on the snout, which I believe is used on chain drive motors. The gear driven MC/RMC motor uses a helical cut gear to mate with that big helical cut fiber gear on the end of the camshaft. Meaning, unless somebody just stuck the straight cut gear on there (everything else about cranks being equal), it doesn't belong to that RMC motor. Also noticed, the counterweights on my gear drive crank are bolted to the crankshaft, not cast into it like the photo. Not sure if that's another indicator or not. Maybe I'm missing something totally. I'm too ignorant of any other tell-tale indications without a lot of research. Rookies!

Is there a Doctor in the house?

That RMC block with that rebuild tag looks pretty good to me. If it has no serious defects, and a good crankshaft could be sourced, I'm pretty sure a competent L134 experienced machine shop could line bore it for the crankshaft properly. The L134 takes very special line boring I've learned --- not like other motors anyway. Can't tell much about the other with the Industrial head on it.

[wesk]

A - RMC68963, early 641087 casting, was a LKY Ordinance Depot rebuild 1959 (bores + .020, Mains & Rod - .010), intake is early civvy

B - No Serial engine, late 641087 casting, Civvy pulleys, industrial head.

[Naugha]

Do not overlook the four different castings used over the production life of the M38 by Willys!

Hello Wes,
The RMC block I have located does have casting number :
641087-l-W-A-N1-CR-N2.

The owner sees no visible cracks but block has not been magnafluxed.

I am trying to decide on an engine plan for the M38.:

* Keep looking (lots of other stuff to do)
* Try to rebuild the CJ2A block in it (scored sleeves)
* Buy a MC block I have located but don’t yet have details.
* Buy the RMC block mentioned
* All the blocks I have located so far would require shipping and not get my machine shop’s inspection.

Also .....
can the cam and drive shaft of a CJ2A be used to rebuild a MC or RMC L-134 engine?

BTW/ My jeep came with a 24v electrical system (maybe origional) but nothing has been tested.

[Naugha]

[quote="RonD2"]Don,
Does your M38 also have the Patent Plate? Do the serial numbers match?

The M38 serial numbers on dash plate and tag behind passenger seat match.
24v system..... much of the jeep looks original with a good body but the engine is a CJ2A.

Note what looks like ‘52’ with an overstrike of ‘55’.

https://photos.app.goo.gl/9qEybGikWJoxQn5T9

[Naugha]

Don,
I figured it out. If you remove the

at the end of the link it'll work.

. Try that.

[Xamon]

Just have to remember that the cam in a gear drive, such as the MC, spins the opposite direction of the chain drive cams such as the MB. not sure which is in your CJ block.

[Naugha]

.....The ultimate question is what kind of restoration are you after? Factory showroom, as maintained in the service motorpool, a restomod, or just whatever the wallet can afford? I call mine a motorpool, but technically a restomod because it's electricals are 12 volt vice the original 24 volt. The 24 volt parts are rare, expensive to buy, and harder to maintain properly. Good luck!

Not Factory. Not new. Not ‘Trailer Queen’. Not interested in shows. Not ‘Rock Climber’. Not ‘Mudder’. Yes road worthy. Yes rides on country roads, dirt roads. Yes reliable small town driver @ 40mph. The 24v system (origional?) came with the jeep but has not been tested. I am finding/reusing almost all original parts, even found an origional underhood battery box that I am refurbishing.

My idea was/is a M38 with so much original gingerbread showing plus a few minor imperfections and a little dust, that at 50 ft. most folks (except you guys and MPVA judges) would wonder if that sucker just pulled off a battlefield through a time warp .... but maybe no stars or insignia. All is still under consideration.

[Naugha]

So, what # is on your title? Is it the # on the data plate, the # on the patent plate, as assigned VIN or the engine #? If it is the engine # does it match the engine you now have?

My Florida title uses the matching ID numbers from the jeep which is what I think was also on the Texas title.

The Florida and Texas titles show the M38 as a 1955 but the dash plate year looks like 52 with a 55 over strike. I will let more knowledgeable folks opine on this possible irregularity.

https://photos.app.goo.gl/9qEybGikWJoxQn5T9

[wesk]

I would suggest staying with a gear drive cam engine to keep all rotational issues the same as the original M38 engine. Remember, the cam drives the oil pump and indirectly the distributor.

Year errors are common with surplus military vehicles because the DMV folks often went with the year listed on the SF-97 form the surplus vehicle left the auction with and they seldom checked serial listings or databases. Usually if you provide your DMV with a serial/year listing that shows the error they will correct it. Most likely whomever registered it originally as a 55 did the overstamp on the dash serial plate.

For a restoration target all indications are you are looking for an M38 that qualifies as a safe daily driver as close to stock as is practicable.

[Naugha]

Ok, I'll jump in here...these are my engines and that's my CraigsList ad.

https://smd.craigslist.org/pts/d/hughes ... 52680.html

I added 9 new pictures today to let Don see more of the RMC block. All of these parts came to me in a buyer takes it all or nothing deal, sort of. I don't have any history on the parts and I can't confirm that the loose crank was originally in this block, but the main caps are bolted in place by whoever took this engine apart.

The Industrial head is bolted to a block with no serial number stamped...this engine is still all together (head to oil pan) and does turn over.

I'll do my best answering any and all questions, but I'm a Jeep rookie als

Mike B

I figured this would happen. It’s like a small town where everyone knows each other. ...... Yes, I am Don in Florida scratching my head about stuff.

Having made a few mistakes ($$) along the way, I wanted to get the engine thing right. This seemingly simple choice is actually a jigsaw puzzle of decisions.

I recently discovered an overlooked strategy for the M38 restoration.... ‘VISA’. Instead of busting knuckles, inhaling clouds of rust and blinding myself with the welder, how about ‘pay’ someone for more usable parts and get an actual mechanic to jump in when my skill set will not suffice.

Sounds reasonable. Right? Nope .... Some parts (especially originals) are hard to find or refurbish and most mechanics in my area don’t regularly work on things like seventy year old Dana differentials.

Anyhoo .... today we are talking about what best to put in the engine bay that would be relatively “reliable”, historically acceptable, passes some basic inspection needs for such purchases, close enough to pick in Central Florida or be shipped without doubling the cost ..... you guys know the drill.

I was thinking of using the CJ2A engine that came with the jeep but the local machine shop man frowned at the idea and ..... well here we are. Plan B.

BTW ..... If anyone would like to revisit the actual topic of this thread, “Scored Sleeves” . I would still be interested in hearing any other experiences or opinions about my CJ2A engine. If it really can’t be refurbished then I can’t use it or sell it .... hmmmm..... coffee table ?

Don