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I've been lurking for a while and finally started some real action yesterday. I picked up a 4bt about 2 months ago and started putting things in motion. Since my Traveler is in pretty good shape it won't be doing any significant wheeling. Since it's set up for automatic, I'll be going for a 4x4 46rh when I can find one for a reasonable price. The passenger side drop of the front axle will make for tricky exhaust routing, but I think it'll work out. If not, I'll fight that battle later.

One of my objectives is to have nothing outwardly indicating that this is any different than any other Scout-- no cutting the hood, no stacks... I'm going to be proud that it's a diesel, but I'm more proud to drive a Scout. The 4bt itself will be painted IH red.

The operational objective is to have the best of all worlds: torque, towing capacity, mpg/range, reasonable highway comfort, etc. Most of its driving will be kicking around town, going out to the beach, and weekend camping trips to the mountains. Just a great all-around Scout. So basically it's going to be what a Scout already is but with better fuel economy.

The 345/727/D20 setup got pulled yesterday, and the engine compartment will be cleaned and prepped in the coming weeks. My 4bt is supposed to already be in good shape, but there's a trusted diesel guy nearby who will be going through the motor to be sure. Right now the task is to thoroughly clean the engine compartment after 33 yrs of the IH factory oil leaks, then establish as much sound deadening/isolation as possible for the passengers.

Where I am, and where I want to go:

The truck has D44s front/rear with 3.54 gears, and the tires are 33-10.50 BFGs. That seems to put the 4bt in a great RPM range for all ranges of driving. Lift is a 4" Triangle with slightly longer-than-stock shackles and Procomp 9k shocks. I have the 33-gal fuel tank and a new Griffin aluminum radiator w/ integrated trans cooler.

The Griffin is the style needed for a SV, so passenger side upper inlet, driver side lower outlet. I think the 4bt can be adapted to fit that, and I'm pretty confident the Griffin has enough cooling capacity for the 4bt. I will be going with an electric fan.

The body bushings on the truck are the factory ones and have squashed over the years; I have a new set that will be installed in this effort. If the 4bt will still not fit, I'll only add enough body lift to squeeze it in, but I hope not to.

The Traveler's A/C works great and we were able to move everything out of the way for engine removal without cracking the refrigerant; everything will be mounted up to the 4bt later.

Question: The A/C heat exchanger in front of the radiator takes up a fair amount of room and I'm concerned about the front surface area recommended for the intercooler. A friend has a Perkins diesel in his truck and the intercooler is maybe 2 sqft. I realize I'll be able to find different shapes/sizes for the intercooler, but how small (or big) would you guys recommend? I'd like to find one that wide but not tall, that can fit below the A/C HX in front of the Griffin.

I share my garage with a drag race guy, and he's going to help me with the intercooler, bracket fab, and other bits. Another nearby Scout guy will be leading the charge on placing motor mounts and cross members. While it's gutted, I'm going to clean up the steering with a lower Borgensen joint (I did the upper already). After the 4bt is up and running, the Traveler will get its axles cleaned up/gone through and get discs all around. At some point I'll cut down the liftgate and install a regular Scout tailgate. I also have a factory Warn bumper and rebuilt Warn 8274 that will be installed. Yeah, it's a bit poser but it looks cool and the winch has come in handy on by buddy's Scout on more than one non-trail occasion.

Feel free to offer critique and recommendations, but don't knock the choice for going with an automatic. That decision has been made. I'm open to suggestions and ideas, even if they're little ones. I'm trying to read other build thread to catch lessons learned but I still have a lot to learn.

A pic of some toys (the 4bt in the foreground will go into the blue/white Traveler in the center) is attached, as well as a solo shot of the Traveler...

:beer:
 

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Discussion Starter #2
Maybe this is more appropriate in the Build-up section? Either way, looking forward to advice. Thanks!
 

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If you search the build up section there are several Scouts there, and I'm sure you know some Scouts came with Nissan Diesels. I'd got with a 47RH from a 94-96 Dodge truck with diesel. It will bolt up, and you can also use the 241 transfercase, and a D44 from a Ford to solve the driveshaft /exhaust problem.

My only reccomendation is don't stress over ride height. Install the engine and all equipment first, and then "correct" the ride height. Many guys waste time worrying about what springs to use, and it is virtually imposssible to preplan. Take your best shot and correct using spacers or shackels. just don't try to correct a 3" problem with shackles. In my experience there is alot less spring deflection with the 4BT's extra weight than most people, including me, thought there would be. I ended up having to "raise" the rear of my Jeep because of this. Always remember, there are 2 springs up front sharing the load, so the spring rate for one spring gets doubled. IE 200lbs/inch is really 400lbs per inch.

Your Traveler looks clean, Do you have the top also?

Randy
 

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Suggestion: ENJOY! That should be a real fun truck when you're done. I've always liked those vintage Scouts, just something about them.

I'd second the 47RH opinion, stronger, more trans for a diesel.

I don't know on the gears, maybe I'm wrong, but sounds too high for happiness. Others may have better info but on mine, 4.1 gears, 30" tires, NV4500 o'drive trans these seem ideal gears. Plenty of power for anything including towin but a nice top end cruising speed, with excellent mileage. I don't think I could pull 3.54's in the mountains or towing, seems like 3.73 max to me for your needs, especailly with 33's.

Again, that only my own partially informed opinion, others may have different experiences on this? Maybe things are different with the automatic...
 

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1989 Jeep Wagoneer, 360v8, 727, stock for now,
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Nice truck!
33"s and 3.73 or 31's and 3.54 is what I'd recommend. (You can always adjust the tire size if you want.) I've been running 3.73 and 33 for 7 years, great combo.
As far as I know you can't get a 46rh to mate with a Cummins. The 46rh bolt pattern was for the gas 5.9 and will not bolt up to a CTD 5.9, Go with the 47RH.
Steve
 

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Discussion Starter #6
The SD-33/SD-33T are dependable engines that will run forever, but they really don't inspire me. The 4bt does!

Yes, I do have a top for the Traveler (see it installed in the other pic). It's in pretty good shape... But I have some rust on my bed rails and in a couple small spots here and there. Nothing drastic, nothing's getting worse since it stays garaged now.

There'll be basically no issue with ride height... The 4bt and the now-removed 345 are about the same weight. I think I read that the 4bt weighs in around 760lbs dry, then I'm going to add an intercooler and other bits. The 345 is a shade over 800.

I think the 3.54's and 33's will be pretty good, but they can always be adjusted later. 3.73's might be better, but 3.54's are what I've got. Might as well run them and see before I swap them.

Any thoughts on my question regarding intercooler surface area? Is there a thumbrule for size, brand, etc?
 

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You'll be fine with the 3.54's and 33's you'll be right in the area you need to be RPM wise.

didn't think about a 345 figured you had a 350 chev motor in it. you won't have to change anything on the susp.

You're gonna be very happy with this swap in the binder.

Randy
 

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Discussion Starter #8
The Traveler's motor/trans/tc have been pulled, as well as most of the rest of the odds and ends. Got the A/C dismounted and moved out of the way... Trying to do the conversion without breaking the seal, we'll see. Pressure washed everything, installed a Borgensen lower steering joint to replace the rag joint, preparing to install new body bushings. The 4bt went to a diesel guy for a one-over and should be back this week.

I thought I had a 4x4 47rh lined up for a good price, but the guy seems to be flaking out on me. Going to go with a Jeep D300 transfer case so it'll be good with my stock front axle.... And if it's not I can get the clocking adapter and go with a DSD front axle later.

For now, the transmission is holding up the show.
 

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Thread moved into the Build-ups section...
 

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On that Borgeson u-joint, may I strongly suggest Loctite on the setcrew & nut? Mine liked to back itself out....
 

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Discussion Starter #13
One step closer-- a 47re came home today, and a Jeep D300 will come home this weekend. Gotta do a little homework to check each of them over.

Still looking for the starter/bellhousing adapter though.

The diesel mechanic with my 4bt had to put mine on the back burner... A guy came in with some serious issues that were more important than my little work. Not only was it a bigger job/more money, but that truck on the road is another guy's livelihood. Mine is for a toy, so I was happy to wait. It should still be done in the next week or so.
 

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Since the stock engine is a bit heavier than a Chevy small block. You are adding approxiamtely 200 lbs to the front of your rig when istalling the 4BT.

That is about the same as a bumper and a Warn 8274 winch.

Scouts have crazy weak springs in them. They are very narrow and tend to flatten out if wheeled or articulated alot. If you decided to lift it or you can stay with the stock rig height after the install, look at the Jeep Wrangler springs. They are very close to fitting.
 

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Discussion Starter #15
As mentioned above, the Traveler has the 345 (weighs in over 800lbs). The 4bt is actually a little lighter than the 345 but with intercooler and other bits it might equal out.

I do have a Scout Warn bumper and 8274 to install, and the Traveler is already lifted on 4" triangles, as mentioned above.
 

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?

Is the axle sprung over or under? Have you cut and turned the knuckles for caster? Have you considered reversing the shackle? Hi Steer?

I am building a 78 Traveler and started a couple years back and the project has gotten more and more extreme. First I replaced theSD33 motor with a 4bt and put an NV4500 and np205 behind it. Then I drove it a short while and blew it back apart for paint. The paint turned my Scout into 1,000,000 pieces because the further I tore it down the further I felt I needed to go. I even blew apart the axles and replaced the clutches to make the posi work again. On the front axle I put the Scout axles in a shortened GM housing and then used chevy brakes and Ford Hubs. I also had the knuckles machined for hi-steer and put them back on with 5 degrees of caster. I put on a reverse shackle kit from IH only North as well. Next I found a p7100 IP for the 4bt and put it along with a new cam into my little machine. Currently my Scout is waiting more body work and paint, and will get it as soon as the Cage, sliders, and bumpers are done. Anyway, your project is exciting and I hope you don't beat me done.
 

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JimmieD: The hot tip on those Borgenson U joints is to use 5/16 G8 bolts, drill the heads, and safety wire them. You can use Loctite too!

I loctited mine heavily with Red Gap Filling Loctite! Almost like I epoxied them in!! Still came loose and got lost on the Swamp Lake trail, and I had to rob a diff cover bolt to put it back together so I could tow another Jeep 10 miles down the hill using his brakes, because a brake line of mine got picked off when I lost the steering, and I had no brakes.

When you are pushing around big tires, the steering shaft flexs just enough to "work" the junction and this makes the set screws loosen.

Remember the Diesel Mantra " if it's tight, it gets loose, if it's loose, it falls off!"

The steering is the absolute last place you want this type of problem.

Another tidbit on Borgenson Joints. Before you install the 5/16 bolts, take a 1/4" drill and drill into the shaft about 1/8" deep, or just past where you are drilling full diameter. This gives the bolt a seat to sit in .

Sorry about the Hi-Jack but this is a fine point that kinda matters.

Randy
 

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Discussion Starter #18
xyz-- lots of good thoughts, but baby steps man! :) I seem to have misplaced my liquid-cooled wallet.... Gotta keep it slow with the classic version.

Randy, lots of good thoughts about the steering don't worry about an important hijack. Brakes and steering are more important than any other aspect of the truck.
 

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overdue update....

Work transferred me to England for a bit, but I've set the Traveler on a course for success while I'm gone. A couple of guys from my Scout club are running with it; full thread below. Some of the initial posts were me figuring things out, but then it gets down to it when Randy takes over.

When Randy's done with sorting out the big pieces, Levi will be doing basically a frame-off restoration/paint. When I get back, it'll be pretty much perfect and better-than-new.

http://www.binderplanet.com/forums/showthread.php?t=88888

Sorry to direct you to different message board, I just don't see a reason to have everything duplicated. I don't make it to this board nearly as much as the other, but I would see questions/comments/concerns in either place.
 
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