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Diesel CJ8???

norstar

Basic User
Bare with me guys, I'm trying to beat CA at it's own game.....

Anybody have any knowledge/experience with a diesel conversion into a CJ, i.e. which motor, mods, did it actually work, etc.

I'm having a hard time finding an '8 that hasn't had it's smog equipment modified, and it's a PITA to get it up to spec. However, if's a diesel they just smile, pat you on the back and send you on your way...Go figure.

Any thoughts?

Kevin
Georgetown, Occupied CA
 

Dwain

Basic User
City
Baytown
State
TX
Diesel

Nostar,
I believe Jefe runs a diesel. He has a web page, but I'm not sure of the address. Look back through the post, I'm sure you'll find it. Hope this helps - Dwain
 

trust

PITA
City
White Rock
State
NM
diesel

There are a couple guys on the SWB board at offroad.com that run 6.5 L GM diesels in their jeeps. CJATE has toyed with the idea a few times but hasn't done it yet. I sort of know a guy in Las Cruces NM who runs a Cummins 4 cyl in his short nose CJ5. In the early to mid 1980s there was a company doing diesel swaps into all the various jeep vehicles but they're probably gone now, they used Perkins I think.

So with all of that crap, I think the GM would be the easiest and I think you can use typical chevy v8 swap hardware to put it in.

I know, no help at all just noise

tr
 

CJATE

R-u-n-n O-f-t
City
NAPOLEONVILLE
State
LA
I think you are on the right track. There are a lot of good reasons to go diesel. Trust is right, I have toyed with this idea for some time. Nobody makes a kit to help, so you have to be pretty resourseful to pull it off. The best choice I believe is the Cummmins 3.9 liter 4BT. It is identical to the 6 cyl used ion the Dodge 3/4 ton pickup but a 4 cyl. The power is pretty good and it is very frugal. The trouble is it is kinda hard to find used and new would be pretty expensive. Cummins also made (still makes?) a small 6 cyl (6AT?) which was used in a bunch of UPS trucks and bolted to a GM Turbo 400, but the power wasn't too exciting. I have read most everything that has crossed my path and I haven't seen a convenient way yet to get it done without big bucks, and still keeping power steering and brakes etc. The chev 6.5 Turbo is a good choice but the injector pumps on the 95 and later are suspect. They are really strong diesels and bolt up to NV4500s as well as the 4L80E autos. They also may be easier to find in salvage yards in running condition. The cost to rebuid the 6.5 can be significantly more than a gas motor. I have also seen some info on the Mitsubishi diesels found in some of their small cabovers and some GM capovers but nothing that concrete. Sorry I couldn't be of more help. The guy Trust mentioned in Las Cruces may be the guy to contact since I believe he has a diesel repair business and his CJ-5 has a Cummins 4BT. Let us know what you find out or decide.

Tim
 

jefe

Basic User
City
Nevada City
State
CA
I've been a diesel fan for many years. I originally bought my present CJ 8, AND a GM diesel V-8, expecting to install it to replace the smog device ridden '6'. I found out to my chagrin that CA smog laws would not permit me to do this. It'swhat they call, "out of class", which means any engine that was only

I've been a diesel fan for many years. I originally bought my present CJ 8, AND a GM diesel V-8, expecting to install it to replace the smog device ridden '6'. I found out to my chagrin that CA smog laws would not permit me (or you) to do this. Besides the legal issues here's my take:
1. Most diesel engines with ENOUGH power for your Jeep are too heavy for the frame, or too wide, or too long.
2. If you can get around the smog laws, a 6 cyl. Perkins would be good. Also, a 3.9L Izusu Turbo , 120 hp, (at least the one captive for GM version) is said to bolt right up to a SM-420 or SM-465. I have a post somewhere of a Canadian Jeeper who installed the Izusu and is ecstatic about it.
[Rob Mullen wrote: I have found what I believe to be the ULTIMATE diesel motor for swapping
into formerly gas vehicles. It's a 3.9l Isuzu turbo diesel that makes
120hp. It's used in those "cab-over" 3(?) ton trucks which I beleive are
sold both as Isuzus (don't know the model number) and as GM 3500s. I
recently saw one in a Land Cruiser and it's a VERY clean conversion. A
factory Isuzu bellhousing is available that will mate to a Chev SM420. All
you'd have to do is get an SM420 (7:1 first gear--should crawl respectably
;) and either an adapter that would go between your transfer case (Dana 20,
is it? I'm not real good with Jeep stuff) and the SM420 OR get an SM420 and
a Chev-application transfer case that has the driveshaft outputs in the
right spot for your Jeep.]

3. Everywhere in the world, except the USA, uses diesel 4x4's as a matter of course. If you could get your hands on a foriegn job and have it imported (?).
4. I drove a 1980 IH Scout Traveller, 3.3L Nissan Turbo Diesel about 100K and loved it. It only made 101HP , but boy the torque with that 80 lb. flywheel was monumental. Since diesels are all fuel injection, you erase one of the snags of carbed gas engines.
5. One of the hidden troubles with Diesels is vibration. I have owned a '79 Cadillac diesel Sevile, and it about shook the car apart. I've also owned Benz 220D, Peugeot 505S T. D., VW Dasher diesel, with varying success. The Peugeot was my clear favorite.
6. My vote is for the 3.9L Izusu Turbo Diesel. Right size, right power, right MPG, monumental torque at 400 rpm, works upside down, sideways, straight down, straight up, not too complex to install, lasts a LONG time.
I still have a thing for diesels, and bought a Dodge Cummins P.U. 2 years ago and couldn't be happier with it as a tow rig.
regards, as always, jefe
 

cj7berry

Basic User
City
rochester
State
nh
I saw and talked to a guy at the essex junction summer nationalsthis past summer. He took the whole engine and tranny ,transfer case out if a 1980 scout 2 and put it in his scrambler. He said the power output wasn't great but he used it for wheelin and he said it was great offroad. Looking at the install it looked pretty straight forward as far as making it fit. He said the biggest thing was placement of the engine and the mounts.
 

Slpbear

Wyoming Scrambler nut
Diesel engine

I own an rV park and have seen many jeeps this summer being towed by different RV's, the one i was interested in most was a 46 2A, He had a Perkins 4 cly Diesel and was very happy with it. I called a friend who use to be a jeep dealer and he said that in the late fifties and early 60s they actually put the perkins in the jeep, mainly the overseas Jeeps. I hope this helps a little. Now finding a perkins is difficult but not impossible from what I understand. The 2A was a sweet jeep, this guy was from Maine.

Thats my 2 cents worth. Dave:)
 

pointer

pointer
City
Mer Rouge,la
State
la
perkins diesel

I live in mid south farm country and there are quite a few 4cyl Perkins around,but a decent used one would cost a couple of thousand unless it eas in bad shape.
 

norstar

Basic User
Diesel-o-rama

Thanks for the input, guys!
Sounds like it's as much of a pain in the a$$ to swap a diesel in as it would be to try to smog a gas motor...Note to Jefe- your website's not up last time I checked, I've been wanting to get a look at your 8!!
All Best,
Kevin
Georgetown CA
 

Aussie Scrambler

New member
City
Mt Garnet
State
QL
I have three 1981 CJ 8 diesel scramblers, made in Toledo as a RHD for export only. They originally have the Isuzu C240. I replaced one with the Isuzu 4jb1, 2.8ltr turbo. Very easy swap and gave me power steering and power brakes. Excellent economy, 8ltrs/ 100klms ( about 30 mpg) good power. Ran with the standard Tremec four speed Dana 300 transfer and 3.7 diff ratio. Next rebuild used an Isuzu 4JG2 3.1 ltr turbo on a AX 15 gearbox with the Dana 300, still with the 3.7 diff ratio. Power is good but economy is down a bit 11 to 12 ltrs /100klms ( just above 20mpg). Currently fitting a bigger turbo hoping to fix the economy.May also try a 4.11 diff ratio. From what I have been able to source I believe there were 300 CJ7 RHD diesels produced for export only, most of which came to Australia, and 270 CJ8 diesel Postals for the Canadian postal service. I have not been able to find how many other CJ 8 were produced.Here in Australia we also have the CJ10, some have a Nissan SD 33 diesel and provided brilliant off road performance.
Aussie Scrambler.
 

walkerhoundvm

Just trying to stay upright
Lifetime Member
City
Cave Creek
State
AZ
I have three 1981 CJ 8 diesel scramblers, made in Toledo as a RHD for export only. They originally have the Isuzu C240. I replaced one with the Isuzu 4jb1, 2.8ltr turbo. Very easy swap and gave me power steering and power brakes. Excellent economy, 8ltrs/ 100klms ( about 30 mpg) good power. Ran with the standard Tremec four speed Dana 300 transfer and 3.7 diff ratio. Next rebuild used an Isuzu 4JG2 3.1 ltr turbo on a AX 15 gearbox with the Dana 300, still with the 3.7 diff ratio. Power is good but economy is down a bit 11 to 12 ltrs /100klms ( just above 20mpg). Currently fitting a bigger turbo hoping to fix the economy.May also try a 4.11 diff ratio. From what I have been able to source I believe there were 300 CJ7 RHD diesels produced for export only, most of which came to Australia, and 270 CJ8 diesel Postals for the Canadian postal service. I have not been able to find how many other CJ 8 were produced.Here in Australia we also have the CJ10, some have a Nissan SD 33 diesel and provided brilliant off road performance.
Aussie Scrambler.
You know you can't get away with saying something like that and not posting pictures, right?
 

Aussie Scrambler

New member
City
Mt Garnet
State
QL
I am not the greatest computer wiz but will give it a go. The three CJ 8 diesels have vin numbers, tabs, tags and Australian compliance plates that determine their authenticity. I know one original owner. It amazes myself, that these three jeeps were manufactured in Toledo and landed in my backyard. I know of one other in New South Wales, Australia and some time ago there was one on a web sight in America ( the one that did not get away). I have not found any others so I conclude they are extremely rare. I refer to them as the unknown jeep rarest of the rare CJ8 Scramblers. Any information as to their origin and number produced would be greatly appreciated. Will attempt to attach pics, which are, three CJ8 Scramblers, latest rebuild, original rebuild and 4JG2 on AX15 and Dana 300.
Aussie Scrambler
 

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DustyBritches

Scrambler Rookie
Lifetime Member
City
Las Cruces
State
NM
diesel

There are a couple guys on the SWB board at offroad.com that run 6.5 L GM diesels in their jeeps. CJATE has toyed with the idea a few times but hasn't done it yet. I sort of know a guy in Las Cruces NM who runs a Cummins 4 cyl in his short nose CJ5. In the early to mid 1980s there was a company doing diesel swaps into all the various jeep vehicles but they're probably gone now, they used Perkins I think.

So with all of that crap, I think the GM would be the easiest and I think you can use typical chevy v8 swap hardware to put it in.

I know, no help at all just noise

tr
Do you have a name for the guy in Las Cruces? Thanks
 

mhinchliffe

CJ-8 Member
City
W-S
State
NC
There was a guy on here a while back that put an OM617 and a 5 sp in his 8. He got t-boned at an intersection if I remember correctly. He had a really nice write up with loads of info and pictures. He also made a parts and cost sheet.
 
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