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Discussion Starter #1 (Edited)
This discussion started on the cummins4bt yahoo group. It was moved here to facilitate future searches.
A few of us have or are in the process of swapping a 4bt into a Jeep TJ.
The pictures and info on our swaps will come soon.
 

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Discussion Starter #2
My current plan is to swap in the engine and TH400 that came with it. I will run it as 2wd to work out any bugs. After I am satisfied I will tackle 4wd. I would like to install a 700r4 for a trans but I do not have one right now. The intent is to use the Jeep 50% off road and 50% street. I am going to swap in a Ford 9" rear diff and hopefully a Dana 44 front.
The stock 4.0 I6 has been pulled out, and the trans and t-case will be out this weekend.
 

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Any pics to go with? I plan a 4BT for my '98 TJ; it might be hooked to a NV3500, since the AX5 is about to go bust. If I replace the tranny soon, I would like to re-use in the future.
 

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Discussion Starter #4
I have taken some pictures but the computer I am at will not read the memory card from the camera. So I must wait till I can use my other computer.
 

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Discussion Starter #5 (Edited)
I have found out that the stock gages will work if you use the stock input sensors through the ECM. The only hang up is the tachometer, but that is still being ironed out.
I also believe the 231 T-case will handle the torque of the stock 4bt, I say stock because who knows how far someone will push the envelope.
I sized up a 79 Bronco 9" rear diff. it is 65" WMS-WMS. The stock TJ D44 is 60.5" IIRC. I think the D44 is a good strong unit, but I came across this 9" with a Detroit locker at a price I could not refuse. So this may very well get used full width with some offset rims.
The D35 front I feel is lethargic at best, especially after adding bigger tires and the weight of the engine.
I saw one 4btTJ where it was manditory to use a "center outlet" exhaust manifold, I was told it is needed but I have not fit my engine into the TJ yet to see if there is a way to use the standard rear outlet manifold.
I saw it mentioned that dual fuel pickups may be needed after removing the stock gas fuel pump due to no baffeling in the tank. I agree dual pick ups will be better than one but I doubt it is necessary. I have seen no stock light truck diesel fuel tanks that employ baffels and they are not having fuel starvation issues. Albeit with after market fuel pick ups we don't run them real low on fuel. am involved in several high performance diesels and some have used sumps, but this leads to issues with sucking garbage from the bottom of the tank.
 

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Discussion Starter #6 (Edited)
Here is the engine just before starting it. I used an old bread cart from the grocery store for a running stand. It worked out very well.
I have edited the photos to be dial up friendly.
 

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Discussion Starter #7 (Edited)
Here is the Jeep, it came with that windshield sticker.
 

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Discussion Starter #10 (Edited)
Here are some pics of the TJ fuel sender/pump I asked about in the last post. Well it will not let me post any more photos so sorry but I guess no more pictures of this 4bt swap, or at least until I can buy a star.
 

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Discussion Starter #11
I was able to remove the trans, transfer case, driveshafts, and drain the fuel out of the fuel tank last night. Yesterday I bought a S.S. pick up tube and bulkhead fitting to install in the fuel tank.
 

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Discussion Starter #12 (Edited)
Wohoo lookie there got a star now!
Here are some more pics then.
S.S. pick up tube with JIC flare and nut, and bulkhead fitting, and a couple more of the fuel sending unit.
 

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I ran SS tubing and two Walbro fuel pickups. Works well so far!

http://autoperformanceengineering.com/html/pickups.html

I'm guessing that fuel tank is non baffeled? while it is probably smaller and not nearly as long as mine, it may not be a bad idea to run multiple pickups. The wallbro will suck shut if it's dry and draw from the other pickup.
 

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Discussion Starter #14
I did a dry install to see how it is going to fit.
 

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Discussion Starter #15 (Edited)
You are correct the tank is not baffled. I have run my pick up truck with a straight pick up tube like the one I made and I have had no fuel starvation issues. I am sure rock crawling might though with the extreme angles they drive. I do like those Walbro suction "feet" I think I will try one just for grins. Thanks for the link.
 

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Gregg,

hey check your starter clearance. I had a problem with the cup that takes the control arm from the axle on the passenger side. there was a major clearance issue. I had to lift my engine up to make it fit. I am in the process of moving my alternator so I can get enough belt touching it. Also the Jeep alternator won't work with out putting an external alternator regulator and I am getting really bad light pulses from the alternator. I am going to put the GM alternator back on the Jeep and that should hopefully fix the problem. On my fuel tank i put a piece of aluminum pipe in the place of the fuel pump.

Donald

http://web.mac.com/my96z28ss
 

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Discussion Starter #17
I did another dry fit with the engine today. I was determined to use the stock Jeep frame mounts, but I have come to the conclusion that they just will not work. Donald I do see where the starter might get in the way. My turbo drain tube is also in the way, as is the A/C condenser in the way of the turbine housing. I will most likely use the forward most holes on the passenger side. The drivers side will use the rear most holes as the P/S pump gets in the way. Plus I want to run an engine driven vacuum pump from a 6bt for the brakes which will put the P/S pump even farther back. This engine is going to sit much farther back than I thought, I might need to "massage" the firewall for exhaust clearance.
Donald on the fuel pump, did you leave the spring loaded cylinder the pump is mounted to in tact and run the p/u tube along side it? What application is your A/C dondenser tank from?
 

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I did another dry fit with the engine today. I was determined to use the stock Jeep frame mounts, but I have come to the conclusion that they just will not work. Donald I do see where the starter might get in the way. My turbo drain tube is also in the way, as is the A/C condenser in the way of the turbine housing. I will most likely use the forward most holes on the passenger side. The drivers side will use the rear most holes as the P/S pump gets in the way. Plus I want to run an engine driven vacuum pump from a 6bt for the brakes which will put the P/S pump even farther back. This engine is going to sit much farther back than I thought, I might need to "massage" the firewall for exhaust clearance.
Donald on the fuel pump, did you leave the spring loaded cylinder the pump is mounted to in tact and run the p/u tube along side it? What application is your A/C dondenser tank from?
Gregg,

My A/C system was custom built by an A/C shop here in Cancun. I am not sure what it fits if you are going to use your A/C you might want to look at the inside of your firewall first. The Heater Core Box sits there and there isn't much room to move the firewall without disturbing the heater/air conditioning box. I removed the fuel pump from the tank and put a piece of aluminum pipe in it's place to still retain the slush tank.
 

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Discussion Starter #19
I have come up with a bad case of "creative block" similar to writers block when you just can't think of how to fabricate something. I just can't seem to come up with a design for the engine mounts that I like. After looking at the passenger side floor I saw that the a/c box was right there and it would limit how far I could move the firewall. Maybe a body lift will work. I removed the front springs and lowered the Jeep down to where the bump stops will be. That way I can see where the link arms will be in relation to the mounts and oil pan.
I rebuilt my TH475, who ever does them for Frito Lay in OH does some very poor work. Bushings were worn, reverse clutch was broken, steels were discolored due to excessive heat but reused after being scuffed up with a grinder, new friction material was used, poor quality converter with a weak design pump drive flange was used as well, it had excessive end play. Judging from the new condition of the friction material the trans was rebuilt recently and all the rest of the issues were just left alone.
 

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I'm looking to do the same conversion on my '97 TJ. I was wondering why you couldn't use the stock fuel pump with a regulator. Eliminate the mechanical pump on the side of the engine. Also run a return line back to the tank from the injectors.

I need to find out what the pressure is of the stock TJ pump.
 
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