Bought a storage yard 1991 Jeep YJ 4X4 a while back. It had sat out in the Florida weather for 5 years and even had the junk yard dog living in it. After 2 years of pestering the owner, they relented and sold me the Jeep for $800.00. We car dollied it a few miles to the house and there it sat. I pharted around with it and after a new in-tank fuel pump, battery and fresh fuel, it started right up and ran nicely Someone had Earl Scheibe'd a green paint job on it over the original white and it was falling off in sheets, shot. I dis-assembled the trim and misc. hardware trying to get it ready to paint. There was one little dent in it about the size of a finger tip and zero rust anywhere, yippie! About 4 months went by with little progress so I decided to send it out to a neighbors paint shop to get it painted. What color??? Blue looks nice. Red looks stanzy, white as it originally came and then I saw a picture of an orange CJ and boy did it pop. I decided on Peterbilt orange with a tan top and interior so it wouldn't look like a pumpkin ride. The additional black trim gives it a nice 3 color finished look so, I am very happy. But what about a diesel engine...

 

Well, I have been keeping my eye out for an OM617.95X diesel engine and finally bought a 1983 Mercedes 300SD here in town. The motor ran like a top with little if any blowby out the oil fill hole. The auto trans. was shot which didn't bother me 'cause I wasn't going to use it anyway. $800.00 for the Benz later and out came the motor. I told the owner all I was really after was the engine and a few loose ends and he said he was interested in the rear window and tail lights so I told him he could keep the car if we could pull the engine out where it sat. He was elated to do that deal. Spent 4 1/2 hours one day with my brother, tools, lift and a trailer and got it out. What a greasy job!

Went through the diesel with a fine tooth comb and had the valve cover, turbo housing, intake manifold and exhaust manifold powdercoat the various colors, they are beautiful to say the least. I bought the transmission adaptor plate, motor mount saddles and oil pan kit from Mercedes4X4 in Tennessee. It is very nice hardware but not without some issues... Once the motor was finished I planned on waiting until school got out to do the swap (my wife is a school teacher) Well, that didn't pan out because the clutch slave cylinder decided to give up the ghost in mid May. I pulled out the transmission only to discover the AX5 had other, more serious issues I completely rebuilt the AX5 with all new bearings, seals and cluster shaft. I also did the 5th gear retainer mod and all is well. As a side note there is a flaw in the 5 gear needle bearing assembly which puts into proper place the 4 absent needle rollers which I rectified before re-assembly.

Well, do I re-install the trans to the 2.5 gas engine or do the diesel swap? Diesel it was. What I thought would take me 2 weeks took almost 5 weeks to complete. I am by nature OCD and have to be owning a precision plastic injection mold making shop. Our adage is this: "There is never time to do it right but there is always time to do it over" So, I try to do things right the first time.

The engine swap went well enough as I gutted out most all of the under hood wiring removing all of the EPA and engine fuel injection wiring, sensors and the such. I then pre-wired all of the needed connections so when the motor went in it was simply plug and play. While the stock motor was out, I painted the engine compartment the matching orange and frame with the new mounts the factory black. It came out purdy. Now comes the problem(s), the engine adapter plate has a design flaw in it in that the Jeep starter motor does not seat squarely to its mount. The clearance hole provided needed to be moved .125 closer to the starter mount otherwise the starter ***** up a little because of what is actually 2 very small but problematic lips in the starter casting. These lips not only cause the starter to ****, they cause the 3/8" allen bolts to bind up as well. Also, I had to machine away a fair size portion of the 3 piece laminated engine adapter in order to just get the starter in place to begin with. Another problem I had was with the oil pan modification. As built per the specifications with the inside front walls required to be flush with each other the timing pin in the harmonic balancer then hits the forward lip on the new portion of the aluminum pan. This had to be ground away as well.

 

The wiring re-work took some figuring but both a Haynes and Chiltons manual helped with color codes etc. I was fortunate in that I only had one small wiring glitch when it was all done and that had to do with the reverse switch at the transmission. Lots of little details took lots of time but it was certainly all well worth the effort. I used the mercedes glow plug driver as well as the Mercedes Alternator connector block. Everything was run it stock flexable wire shield and retainers. Under the hood looks better than factor new except for the K&N conical air filter.

Everything operates as it should. Had a guy at the fuel pump excitedly quiz me as to why I just put diesel fuel in a Jeep. I thought he was gonna wet his pants when I showed him under the hood, what fun. FWIW, I have about $10K in this whole adventure. I did all of the work myself except the outside paint. Yes, I'd do it again in a heartbeat!

Whats left? Re-install the A/C, a functioning tachometer and I am not happy with the limited, tight oil pan clearance so I have a 2 1/2" lift kit on order. This YJ with see very limited, mild off road use so don't rag on me about the transmission and axles etc. This is my fun daily driver. I raced the Baja 1000 in 1981 on a Yamaha YZ465 and don't plan on doing the same with this

Enjoy, I will!

 

First mileage check today. Went from 14.5 mpg with the 2.5 gasser to 22.2 mpg with the diesel. This includes getting on it multiple times as well as all around town driving, no highway runs yet. Nice sounding turbo spool-ups too. Will see what the next tank will provide

 

Quick video of the engine running...

 

Nice job! got an 81 i am doing in the near future, got all the parts just need time.

 

W O W !!! The JEEP looks like new

 

24.4 mpg this tank which was 100% all around town driving. Sure beats 14.5 mpg as a gasser

 

really good. i can see you unturned every stone in your project

 

Hello- New to forum . Do you know what part# the coolant hoses are- both radiator and

heater core hoses.

I have been racking my brain at the autoparts store trying to find needles in a haystack!

Nice clean build you did- really sweet and factory looking