Build Thread 1974 CJ5/1.8L 4FB1 Isuzu Diesel
DieselJeep
Jeeper
Hi everyone.
New to the site. Lots to learn about my new project, a 1974 CJ5, with an 1.8L 4FB1 Isuzu Diesel. My build is a first to me in almost all ways. This is my first 4x4, and is the first diesel I have ever owned personally.
The 1.8L 4FB1 I found on CL, out of a Chevette, with @ 55,000 original miles. Auto trans was left behind, as of no interest to me whatsoever. Got it cheaper, too. I have been meditating on the concept for a year, so when I saw the 1.8L, I did some fast research, and I jumped. Parts seem to be a slight concern, but they are out there. But the tiny size and proven reliability should more than compensate. Actually just spoke with a guy who has plenty of spare motors just a few hours away...
And for those out of the loop, these weigh @ 368lbs FULLY DRESSED, and have almost ALL the features of a high end boosted diesel. Piston squirters, beefy rods and crank, ect...
Goals of the project are:
1) Mechanical injection exclusively. NO electronics on running motor. I don't care if it hurts economy slightly.
2) Cheap Fuel The ability to dump nearly any kind of waste/junk oil into the tank. Constructive input welcome here, but I have personally seen everything from used soybean oil, used motor oil, to old auto trans fluid used in various diesels (including common rail). No strange additives, mixing, ect. Works great, cheap, and easy. I have seen mid 90's Ford common rails burning just about anything. My personal thoughts are if the "junk"(filtered to 1 micron) is cut with diesel #2, you would have no real concern. Diesel #2 has a much higher sulfur content, which is very slippery...And #2 is STREET LEGAL in a diesel older than mid or late 90's(correct me if I'm wrong for OH at least). Just read the placard on a diesel #1 pump the other day. It said RECOMMENDED for older than late 90's...
3) Power Perhaps @ double or triple factory HP, which is possible.
4) Reliability
5) Simplicity
6) Cost (as in, as little as possible), but with a huge nod towards safety and reliability. And after buying the CJ, and the motor, I am WELL under my goal of > $2,000 so far. And still have plenty $$$ for trans., transfer case, and tires(which I feel will be the pricier items).
7) Fuel economy I know a 4x4 brick is not efficient, but if I can bag 30-40 MPG on the highway, I'd be happy. And no I don't want huge knobby swamper/mudder tires.
I noticed a Isuzu P'up at another site, that is running an Eaton M90 SC. Works very nice. Used Cummins 4BT boost timing components installed inside of the Isuzu "Altitude Compensator". I am awaiting some more info on the successes/concerns of the mod. It's of particular interest to me as the gentleman I bought my 1.8l diesel from threw an M90 in, along with a inter-cooler(i believe from a Saab). It reminds me of a modern radiator, with plastic tanks on either side.
However in the mean time I am tossing the idea @ of using it, as it is on hand, free and ready to roll(as far as the unit itself goes). Versus trying to buy/ship a turbo(or two) that probably wouldn't be quite right anyways. I noticed the T25's are too big really, and the T-15's seem small. To use the turbine side of a T-15, and compressor from T25, well, there's 2 used turbos I gotta buy, still have to have it balanced, rebuild the unit. Then fab pressure oil line, return...
Prelim very rough calculations if I were to use the M90 reveal @ 1 to .95 (appx) drive would yield @ 12- 15psi at 6,000 RPM's. The blower would live dang near forever. I know TECHNICALLY the M90 is way too big. But it's THERE and READY. I think personally for my project my goals are to get full boost at 5,000RPM(this motor's Red Line), and keep it conservative, as I won't go that high often(hopefully). I'd like to HAVE the power there, available, but actually use it as sparingly as possible(so I don't stand out like a lil ol' lady angering everyone else merging with traffic!) My biggest concern is parasitic losses @ cruise, and at redline. Tiny motor can't afford much HP to spare...But decent economy is also a factor, but then it WOULD be uber reliable, and 150 lbs torque is fine... And perhaps I could wire up a on/off switch to a A/C clutch, ala Mercedes Benz and/or Mad Max.
All the project goals are slightly variable, to a point...
Any thoughts?
New to the site. Lots to learn about my new project, a 1974 CJ5, with an 1.8L 4FB1 Isuzu Diesel. My build is a first to me in almost all ways. This is my first 4x4, and is the first diesel I have ever owned personally.
The 1.8L 4FB1 I found on CL, out of a Chevette, with @ 55,000 original miles. Auto trans was left behind, as of no interest to me whatsoever. Got it cheaper, too. I have been meditating on the concept for a year, so when I saw the 1.8L, I did some fast research, and I jumped. Parts seem to be a slight concern, but they are out there. But the tiny size and proven reliability should more than compensate. Actually just spoke with a guy who has plenty of spare motors just a few hours away...
And for those out of the loop, these weigh @ 368lbs FULLY DRESSED, and have almost ALL the features of a high end boosted diesel. Piston squirters, beefy rods and crank, ect...
Goals of the project are:
1) Mechanical injection exclusively. NO electronics on running motor. I don't care if it hurts economy slightly.
2) Cheap Fuel The ability to dump nearly any kind of waste/junk oil into the tank. Constructive input welcome here, but I have personally seen everything from used soybean oil, used motor oil, to old auto trans fluid used in various diesels (including common rail). No strange additives, mixing, ect. Works great, cheap, and easy. I have seen mid 90's Ford common rails burning just about anything. My personal thoughts are if the "junk"(filtered to 1 micron) is cut with diesel #2, you would have no real concern. Diesel #2 has a much higher sulfur content, which is very slippery...And #2 is STREET LEGAL in a diesel older than mid or late 90's(correct me if I'm wrong for OH at least). Just read the placard on a diesel #1 pump the other day. It said RECOMMENDED for older than late 90's...
3) Power Perhaps @ double or triple factory HP, which is possible.
4) Reliability
5) Simplicity
6) Cost (as in, as little as possible), but with a huge nod towards safety and reliability. And after buying the CJ, and the motor, I am WELL under my goal of > $2,000 so far. And still have plenty $$$ for trans., transfer case, and tires(which I feel will be the pricier items).
7) Fuel economy I know a 4x4 brick is not efficient, but if I can bag 30-40 MPG on the highway, I'd be happy. And no I don't want huge knobby swamper/mudder tires.
I noticed a Isuzu P'up at another site, that is running an Eaton M90 SC. Works very nice. Used Cummins 4BT boost timing components installed inside of the Isuzu "Altitude Compensator". I am awaiting some more info on the successes/concerns of the mod. It's of particular interest to me as the gentleman I bought my 1.8l diesel from threw an M90 in, along with a inter-cooler(i believe from a Saab). It reminds me of a modern radiator, with plastic tanks on either side.
However in the mean time I am tossing the idea @ of using it, as it is on hand, free and ready to roll(as far as the unit itself goes). Versus trying to buy/ship a turbo(or two) that probably wouldn't be quite right anyways. I noticed the T25's are too big really, and the T-15's seem small. To use the turbine side of a T-15, and compressor from T25, well, there's 2 used turbos I gotta buy, still have to have it balanced, rebuild the unit. Then fab pressure oil line, return...
Prelim very rough calculations if I were to use the M90 reveal @ 1 to .95 (appx) drive would yield @ 12- 15psi at 6,000 RPM's. The blower would live dang near forever. I know TECHNICALLY the M90 is way too big. But it's THERE and READY. I think personally for my project my goals are to get full boost at 5,000RPM(this motor's Red Line), and keep it conservative, as I won't go that high often(hopefully). I'd like to HAVE the power there, available, but actually use it as sparingly as possible(so I don't stand out like a lil ol' lady angering everyone else merging with traffic!) My biggest concern is parasitic losses @ cruise, and at redline. Tiny motor can't afford much HP to spare...But decent economy is also a factor, but then it WOULD be uber reliable, and 150 lbs torque is fine... And perhaps I could wire up a on/off switch to a A/C clutch, ala Mercedes Benz and/or Mad Max.
All the project goals are slightly variable, to a point...
Any thoughts?
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