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Discussion Starter #1
OK, from what I can see, you can buy basically two different "engines" the one without the intercooler that has about 200+ lbs torque and the intercooled one with 400+lbs torque. Is one more desirable then the other? I'm building a 1952 Willy's Jeep truck into a rock crawler and would love to go 4bt..... My son is currently in diesel mechanic school, so it would be fun for him to work on. Any info is appreciated, thank you!
 

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The main issue is whether or not you have enough room in front of your radiator to mount an I'cooler. Your Jeep might not have enough length. The is at least one person here who has done that with a Willys truck, don't know if he has an I'cooler, though.
Also need to consider the weight of the Diesel engine, a modern D-44 would be adequate, but not an old 27 or such. Also need to allow for a cruise RPM in the 1,800 range for most efficiency, that means some kind of close ratio trans. and high diff. ratio, many OD units are too long, a 5 speed trans with OD and married transfer case, right drop, would probably work.

Ed
 

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Discussion Starter #3
Edpruss, thank you for your reply. I like the torque in the inter-cooled motor, what are guys getting out of the non-inter cooled engine?
 

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First off, no road use 4bt had 400 lb ft of torque. That number was on the stock 160 HP 6bt found in the Dodges. The base 105 HP engine had 265 lb ft. Next up in the line was CPL857 which had the water aftercooler. That one is 120 HP and had around 300 lb ft torque. The king dog in the group was CPL1839 which had the P7100 injection pump and was air intercooled. That one was 130 HP and had around 325 lb ft torque. You'd probably need to tune one to around 160-175 HP to get 400 lb ft. Would definitely need a intercooler when upping the power. You'd also want a better turbo than came on the 105 and 120 HP models, especially for crawling around.
 

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Discussion Starter #5
OK, the tag on the engine says 420ft lb torque at 1600 rpm, so what am I looking at here? I know, very newby questions here...
126687


 

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Discussion Starter #6
I know the pic is not that clear, but the link takes you to the engine for sale as well.
 

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I read only 2 digits in that grainy Ebay screen shot - maybe 43 lb ft ???

Ebay is for selling stuff - Technical research should be done on more trusted web sites
 

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Discussion Starter #9
No, it is definitely 420 ft lb torque on the engine tag.... You are saying that is not an option?
 

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Feel free to believe a grainy Ebay picture and ignore the advice of one of the most experienced posters here (that is not me). Did you notice the word "ELECTRONIC" in the "(unreadable) Timing Code line?

Without knowing the CPL# and a clear picture of ALL of the engine tag, this is a mystery motor. Any advice is throwing darts while blindfolded. I will concur with char1355's opinion that 420 ft lb is usually 6 cylinder territory.
 

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Yes, that helps and yes that looks like a Cummins tag

And I eat my words, it does say 420 FT-LB @ 1600 rpm. I am concerned that you are buying an engine before you understand some of the issues of a diesel conversion.

This is NOT a 4bt, it is the newer ISB 145 with electronic fuel injection - I know nothing about the newer electronic engines.

"This engine is not certified for use (hidden by dirty plastic tape). You really need to know (and understand) what these restrictions are. In rural Arizona, currently there is no smog tests, the bigger cities have smog tests. Most likely, a 1952 Jeep truck is exempt.

The folks at the Reno, NV got real excited when I drove my 4bt thru the motor vehicle inspection lane ("1/2 ton trucks never had a diesel engine!!!!"). Calmed down after I assured them that the travel trailer was being titled to my son and I would soon depart NV and take this truck with me.
 
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That's not a 4bt. That's an ISBe 3.9 common rail engine with 145 HP and 420 ft lb torque. Don't often see the 145 HP model. Most on road units were 170 HP. That engine can be a lot more complex to install since it's all computer controlled. Even the accelerator pedal is electronic. Also, those engines only had an SAE3 or possibly SAE2 transmission adapter. They normally had Allison transmissions which are tied into the computer on the engine. That particular engine has the Eaton 5 speed. Good transmission but does not have an OD gear. Pretty sure that one is an SAE2 mount. You could replace that with an Eaton 6 speed with OD but those are very expensive. We have a few members who have done installs with that type engine. That thing has more torque than the 6bt found in the Dodge.
 

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Rear gear train ISB. Charles responded right before me. Anyone know how to delete response or is it even possible on this new format?
 

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Discussion Starter #16
Thank you all for the replies. I am not going to buy this particular motor, it is just an example... I've just begun looking into the idea of using a 4bt. I am not sure it is the right engine for what I am building, but i love diesel engines and my son is going to diesel mechanic school, so it would be fun for us to work on, I think.
 

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A 4bt is a true mechanical diesel. At the most you only need 2 wires for it to run, one on the injection pump solenoid and one for the starter. If you change the injection pump to manual then it's 1 wire. Not sure how much your son may learn about these engines in school. They are sort of dinosaurs compared to the modern electronic stuff. The main thing is there seems to be about a zillion fewer things to go wrong vs the computer engines.
 

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Yes, that helps and yes that looks like a Cummins tag

And I eat my words, it does say 420 FT-LB @ 1600 rpm. I am concerned that you are buying an engine before you understand some of the issues of a diesel conversion.

This is NOT a 4bt, it is the newer ISB 145 with electronic fuel injection - I know nothing about the newer electronic engines.

"This engine is not certified for use (hidden by dirty plastic tape). You really need to know (and understand) what these restrictions are. In rural Arizona, currently there is no smog tests, the bigger cities have smog tests. Most likely, a 1952 Jeep truck is exempt.

The folks at the Reno, NV got real excited when I drove my 4bt thru the motor vehicle inspection lane ("1/2 ton trucks never had a diesel engine!!!!"). Calmed down after I assured them that the travel trailer was being titled to my son and I would soon depart NV and take this truck with me.
 

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sorry but there were certainly diesels in 1/2s, there were hundreds orphan FC170 jeeps sold to marines/navy and airforce and perhaps to utility companies, with the cerlist 3 cylinder 2 strokes, moaners,, then there were thousands IHC scouts with the LD33 2.8 liter diesel versions of the 240 Z motors, and then the dodge wi mis\tsubishis 2436 cylinder in half and 3/4 tons, have fun, let us know
 
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