Who's Happiest?

Hey gang I have a question. My engine in my M38 looses oil press & starts to rattle after about 20 min running. Engine has never been out. I patched it with 4 rod brgs, piston rings & a broken piston replacement 20 yrs ago. So, all you boys who have re-powered your little flatfenders who's happiest with their re-power? Who would do it different? Who wouldn't do it over at all? Who's wife threatened to shoot them if they didn't get that pile of parts running? I'm leaning towards the 153 Chevy, have found several close by but I've yet to lay my hands on any manifolds! Just so yall know, I live out the country, 16 miles from a Walmart so I would not be driving to town, it would still be a 45 mph Jeep around my place & the community. Only thing I would rather keep the Ross steering since it is all rebuilt. I don't want to chop this Jeep up & I may wind up just re-doing the 134. Thanks!

 

…but I doubt you (or anyone) would want to go through what I did.


The Chevy is a solid platform. Just don’t cut the hood to make it fit!

 

Me thinks it just needs it's OEM engine rebuilt. You've got a very nice Rig there. I would keep it original. Just Say'n

 

I'd keep it OEM original, or go Dauntless.

 

If it wasn't so original, I'd say a Dauntless 225 V6 or a Chevy 4.3 V6. Since it's so original and you're not going to be driving it on the highway, I'd just rebuild the flathead.

 

Well, it's PRETTY Original...I still run the 24V waterproof distributor but I have an external 12V coil & a 11SI Delco. This Jeep came from a State of Arkansas Sale way up above Little Rock. They were using it to stripe the roads with. It didn't look Nuthin then like it looks now! But all that paint they spilt on it saved that metal!
Yeah this summer I'm gonna pull the engine / trans / transfer case out & do something. I need to use this Jeep but I don't want to ruin that little engine either. I wish I could mate a little 22R Toyota to that T90 but I don't think that's doable...I know keeping the Ross steering hobbles the project. In 1975 I helped a friend put a 289 Ford in an M38, that's a job I don't want to repeat!
What I thought about doing was getting me a John Deere Gator & selling this M38. But the grand daughter likes it. Besides, I can re-do all the driveline in this Jeep for Half what a used Gator would cost!

 

A lot of people have gone with the 4.3 and love it. I love the original Jeeps and think this one is worth a rebuild. Very nice looking M38. That being said, there are a lot of well-done, re-powered Jeeps on this forum that are very well engineered. One of the guys in the AACA club rebuilt his F134 in his basement and took his Willys wagon on a nationwide tour to all the National parks. That was one sweet running engine. I like having the original electrics and running gear in my military Jeeps, but they aren't daily drivers. If I did do a repower, I would keep all the stock parts so I could reverse it if I chose to.

Dave

 

Got an old Toyota pick-up with the 22R. Was always going to do a 4.3 swap, but a timing chain, valve seals and weber carb is all I've had to do to it to keep it going. It won't quit. If I could just keep the bed from rusting out, I'd be good. Another back burner project. I think this one is worth an OEM rebuild.

Dave

 

I would rebuild the 134 if it passes a torn down inspection. Otherwise the chevy 153 or a ford 2.3 would pep it up nicely if they fit. The 225 and 4.3 really wake them up but it puts a lot of stress on the other systems.

Fwiw I swapped my 4.3 in about a month but they are tall in tbi and carb form. The 225 fits better but takes some air filter tricks. A mpi 4.3 fits the best but they are 200hp 260ftlb... a lot more than you need.

 

Hard pressed to swap in something new, given your use and the retention of the Ross system (and presumably brakes).
Quickest, easiest is a rebuild. Raise the compression a tad and bump up the timing.
Next is a swap to an F head (with a corresponding junk hood to hack up).
Everything else is fairly entailed and somewhat irreversible.

 

Rebuild the flat head and enjoy.

 

Plus the Jeep would still be fine in ten and twenty years from now.

 

The cost to rebuild any motor has at least doubled in the last few years. Stick with tried and true if doing a swap. Buick v6 is almost always the easiest. If it is a forever yours Jeep it is probably best to find another running L head.

 

I would say rebuild what you have.
If the engine isn't a rebuild candidate I'd go for an F-head swap BUT find the Holley one barrel carb that allows the hood to be kept original. I had an MB with an F-head swapped in using the Holley. There may be other carbs that allow this but I know that Holley made one that works.

 

I often give this place recommendation. I have an excellent remanufactured Dauntless from them. The cost was easily worth the time it would take to chase parts and labor.
I now see they will paint your engine in a variety of colors.
It looks like you can get a L head or F head here.
SANDJ Engines

 

First, not sure why anyone would suggest trying to put a (wt)Fhead in a M38. First, it won't fit without fugly mods. and second, like most of the population it's overweight and under powered. I had one in a Wagon for years, biggest waste of time and money...
If you're going resto-mod, go with something that fits like the V6. IMHO, the overall stock look of your Jeep is paramount especially to value. But IIWM, I'd opt to keep it stock engine as well. The place @dnb71R2 mentions above seems reasonable; swapping in an exact fit is just the easiest and fastest thing to do, getting you back on the road and trails with the least amount if hassle.

 

My search showed only an Overhead Valve L-4. That is a very rare Jeep engine.

 

I just brought home a MB with an F-134 and a ford carb and you could close the hood without cutting it up,I have a flat 134 Im putting back in.....my vote is to overhaul what you have and run it...

 

I think id start by replacing the oil pump. Nothing to loose. What oil are you running?