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1980 Scout II gets a 4BT

135K views 113 replies 37 participants last post by  scout4bta 
#1 ·
I'll be putting a 4BT from a Chevy P30 stepvan into a 1980 International Scout II. I just picked up the Scout yesterday, took it in today to get titled, just in time for a snowstorm. I'm including a picture that I just took a half-hour ago... haven't even gotten it off the trailer yet.

I've run a few other threads about some questions I have, mostly transmission questions. Much of that is not worked out yet.... but will be in time.

I paid $1400 for the Scout (actually I still owe her $900, but she's nice, and she's my neighbor!). The Nissan Turbo-Diesel engine apparently is in need of a rebuild, and in any case the injector pump is missing. The body is pretty straight, there's no rust, the interior is OK (driver's seat really needs help), the glass is all good, the top has never been off, and the tires are crap. At first I thought $1400 was an awesome deal... but I'm having some second-guesses about that. Oh well, I only drove 12 miles to get it.

I'll be doing a spring-over-axle lift, putting 3.07 gears in the axles, putting in the 4BT (obviously), and trying to use the Warner wide-ratio T19 that's already in the Scout. I am even considering fabricating whatever bellhousing and adapters are required. If I can successfully mate the T19, then the transfer case should be easy. I'm actually hoping to keep the transmission in pretty much the same place, that way I won't have to relocate the shifters. We'll see about that, though.

I'll try to post a lot of pictures. They will only come as often as I actually work on it though!

 
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#3 ·
The T19's that IH put in Scout Diesel was a close ratio. If you put a wide ration in it you'll be shifting on the gonverner to get moving, that is if this Scout is going to be driven on the street much.
International put in a close-ratio, which they specified on the line item sheet as T-427, and a wide ratio, which they called a T-428. I've got the wide-ratio.

But I don't quite understand "shifting on the governor to get moving." I am going to be driving it on the street... in fact that's primarily how I'll be driving it. So I'm a little worried.. what exactly does that mean?

Thanks,
Christian
 
#4 ·
Do you mean that I'll have to rev the cummins all the way up to it's governor limit in order to be able to shift into the next higher gear?

I just looked at the gear ratios of the T19 close versus T19 wide, and I think I see what you're talking about....

C
 
#8 ·
Before you start the conversion, consider a 5 speed manual overdrive transmission........especially since most of your driving will be on the street.
X2 it would be nice to keep shifters & such in the same location, but a close-ratio 5 speed would probably work a lot better for a DD. With your current transmission, you will have to rev. the engine out of it's comfort zone to get it rolling, then when you shift the rpm's will drop Way down below the power band. I am probably exaggerating a little but the idea is to keep the engine as close to it's peak torque rpm as much as possible (generally accepted as ~1,700 rpm for a stocker).

I didn't notice what tires you're planning to run, a spring-over on a Scout gets Really Big fast :)


PS: Bonus points for the square-headlight Scout :)
 
#7 ·
I drove my stock diesel scout for a few years with a close ratio t19, it needed fifth bad. can't imagine using that trans with a non-revving 4bt! even worse with a wide ratio trans. good luck though. its still gonna be fun.
 
#10 ·
OK, yes, I understand the revs/shifting problem that everyone is pointing out as far as the wide-ratio T19 trans. This is a great example of why forums like this are so helpful... I get to take advantage of the experience and knowledge of all of you, who know more about this than I do!

Funny how the discussion of this build keeps coming back to the transmission. I had been hoping to go with an NV4500, until I realized how little money I had to do this conversion. The money problem made me really investigate keeping the T19 I already have in the Scout, but this "high-revs-to-shift" scenario sounds like a real drag. Plus, I don't want to go through a whole build-up only to find I put all that money and time into the "wrong" set-up.

So now, it seems that selling everything I'm not using from the stepvan and the Scout, and trying to leverage that cash into an NV4500 may actually be the smarter move.

In any case, I had hoped to keep this thread focused on the actual build.. filling it up with photos and discussions of what I am ACTUALLY doing. I have been running another thread for a little while now about the transmission question, called "TH400 vs. T-19... " and located in the Transmission discussions section. I'm going to take the valuable input from the last few posts in this thread and try to transfer the info back over to that other thread.

As usual.... Thanks very much everyone!
 
#11 ·
If I have my ratio's right the wide T19 is:
1st 6.32
2nd 3.09
3rd 1.69
4th 1.00
With 3.07 gears, 33" tall tires and the T19 wide,
Shifting at 2500 in first puts brings you to 12.61 mph, in 2nd that's 1220 rpm.
Shifting at 2500 in 2nd again gets you to 24 mph, or 1350 rpm shifting into 3rd. Shifting at 2500 in 3rd get you to 45 mph and your pulling about 1450 rpm in 4th.
You also be cruizing at 58 mph turning 1900 rpm. Top speed with the factory governer is 75mph with this setup.
Once you go past 2000 the pump fueling goes into the porformance range and your mileage will suffer, if that is a concern to you.
If you want good mileage and speed your going to need a OD.

All of this info is approximate.
 
#12 · (Edited)
The easy part is coming along. I dragged the Scout into the shop and started tearing it down. Front axle is off (for gear change and spring-over-axle lift), and the Nissan engine is an hour or two worth of work away from being out of the truck.

I am still very unclear about how the transmission issue will eventually work itself out. Currently leaning towards a close-ratio T19 or a five speed from a Dodge, if I can find a reasonably priced one.



 
#13 ·
Nice lookin' shop. Good to see it's progressing well. Best of luck with the trans (hope you find a 5 speed out of a Dodge for cheap).


You appear to have a dearth of jackstands under it though. Yeah, I can see three of them, have to figure there's a 4th I can't see (or it wouldn't be sitting level). Call me paranoid, but after I lost a racing buddie to him getting crushed under his 911 (after the 2 jackstands on that end came out from under it) I tend to like lots of them (got any more?).
 
#14 ·
Good looking scout, I would also go with a 5-speed, to use the T-19 with a 4bt you will need to find a Ford t-19 or have a spacer/adapter built to use the Scout t-19 and a overdrive would be a must with the 4bt. I have a 1980 Scout turbo diesel, and with a t-19 wide it sucked to drive, 1st was to low and 2nd not low enough to start, with out slipping the clutch, the close box in it now you can use all 4 gears and don't have to slip it thats with 3.73"s and 33's, not to many of the diesel scouts had wides most where close boxs do to first being to low and 2nd to high. I have a few buddies with Scout 2 4BT swaps and all are using a NV4500's and love them, good MPG and good performance. I would also find a driveside drop t-case and front axle then you don't have to fight the exhaust and driveshaft clearance on the same side. $1400 for a clean diesel scout you can't beat that, i would have jumped all over that, i have had 63 Scouts and finding a clean one is pretty hard even in Colorado.
 
#15 · (Edited)
Good looking scout, I would also go with a 5-speed,
Yes, I am going with a ZF 5 speed. Van, a member on here, made me an offer on a ZF that I couldn't turn down. I think it will work out well. It's a big-block pattern transmission, and I can't afford the adapter from FordCummins.com, or from Destroked.com, so I will machine one for myself.

I would also find a driveside drop t-case and front axle then you don't have to fight the exhaust and driveshaft clearance on the same side. $1400 for a clean diesel scout you can't beat that, i would have jumped all over that, i have had 63 Scouts and finding a clean one is pretty hard even in Colorado.
Yes, I am starting to look around for a driver's drop front Dana 44. May have found one from a waggoneer. I'll look around in the forums here to see how much mod work will be required on the Waggy 44, but if it's easy, I'll probably get it, because I already have a driver's drop t-case.

I'm glad you think $1400 was a good buy. I'm trying to keep this build low-budget, and with no tires and not running, I wasn't too sure about the buy.

Both axles are off the truck, and open. I opened them to change the gearing to 3.07, but now with the ZF, I may just leave the 3.73s in there. Not sure yet. I also pulled the axles to do the spring-over conversion, but now with the possibility of getting a driver-drop Dana 44, I might save myself some work there, too. I already pulled the 3.73s from the rear pumpkin, so now I get to re-install them with new bearings and shims and stuff... FUN!

I chose yesterday, a bitterly cold and snowy day, to pull the 4BT from the frito-lay van. I wanted to leave the van as intact as possible, so I decided to pull it through the door! It worked out OK, but my awesome crane truck really made it possible. I thought this was pretty amusing, I'm sure some of you will too. Pictures below.







Next up, pull the TH400 off the Cummins, machine the big-block adapter, cobble the clutch together, and get the ZF on there. And, try to get that front axle, figure out how to make the hubs and everything else go together, etc, etc, etc!
 
#16 ·
The waggy axle swap is easy to convert it from 6x5.5 bolt pattern to 5.5.5 bolt pattern using all the Scout 2 parts you currently have. Use the Scout 2 steering knuckles, tierod, spindles, hubs, rotors, calipers and caliper mounts and Scout 2 stub axle shafts and your done, now if you are going SOA i would find a set of GM flat top knuckles (mush more common then the 1974/75 IH trucks/t-call knuckles) take them down to a machine shop and have them redrilled from the GM Six bolt spindle mount to a Scout 8 bolt and have them machined and tapped for a steering arm and you have flat tops for crossover steering and all scout parts from the stub shaft out. Now if you don't want to have to have the knuckles drilled from the 6 to 8 bolt you can use the waggy calipers, caliper mounts, waggy stub axle, with GM spindles (the waggy spindles may work) and ford 1/2 ton rotors and hubs to get the 5x5.5 bolt pattern and a internal style locking hub.
 
#64 ·
That is alot of work. Do the Waggy/Chevy spindle route like he said

Go get a set of 1974-77 GM or Jeep D44 knuckles backing plates calipers & spindle most wrecking yards $50 +/- $100 on a bad day. Go to Kragen/NAPA or where ever and buya set of 1980-86 ford bronco/F150 rotors and hubs with bearings (or get those from the wrecking yard too) Put the ford hub and rotor onto the chevy spindle don't change the bearings, use the Ford bearings and run it.

No excessive and expensive machine work unless you machine the knuckle on the pass side for studs and high steer
 
#17 ·
I'mCold

A guy could catch Pneumonia just looking at the pics !! I just put my coat on & wish my insulated boots were not packed away. I agree run the 3.73 you have nothing to loose. I think I can hear that Johny Cash song= One peice at a time. From what I've heard about your fab skills this is going to be a walk in the park for you.
Van
 
#20 · (Edited)
I think he said the motor has no Injection Pump and needs a rebuild. Parts for the SD33T are prohibitively expensive. The cost to freshen one in the USA could possibly exceed $5K in parts alone based upon the few parts I've helped procure. Overhaul kits are like $1300, a head may be required and that is like $1400, turbos are $1000 or more, and it continues from there. Plus most parts would come from down under or Japan. You can find stuff here but it can cost 2-3 times as much as from AU even if you factor in the long wait and shipping from there.

Also, when you get done, you still only have 101HP (@3800 RPM) and 175 ft-lbs (@2200 RPM). The rev range is a bit more useful than the 4B and the mileage is about the same, so I guess in the end it is somewhat of a wash.

A bit late to the party, but.... If you can get your hands the T-19 close ratio, consider the following info, if not skip to the "What size tires" part.

Is there a SAE-4 housing for a B-Series? If so, this could be a bolt in (with no OD) with the existing drive train. Although, SAE #3 to SAE #4 adapter would be a straight forward stepped ring with no funny business or math required. Just that a SAE #3 is 12 13/32 bolts on a 16-7/8 circle and SAE #4 is 12 13/32 bolts on a 15" circle. OD of the #3 is 17-3/4, ID is 16-1/8 (for the pilot step on the adapter) and ID of the #4 is 14-1/4. Easy to make, just have to make sure the flywheel for the #3 is the correct thickness to make the clutch and pilot bearing fit properly because I do not remember the depth of the #3 or the stickout of the input shaft on the T-19 (T-427 Wide or T-428 Close).

But you could possibly make a spacer for the flywheel if you recessed the starter into the housing by an equal amount, although you could probably only get 1/4" and would need a good machinist to ensure the starter was still square.

Or with a bit of funny business, you can make an adapter with a Z shaped cross section and adjust all of the depths there (probably the easiest). Apologies for the crappy picture, but red dashed line is the center, yellow the #3 flywheel housing, blue the #4 transmission housing, black the flywheel, clutch, input shaft, etc., and Green the adapter for #4 to #3. Obviously it will take a bit of math to figure out the exact dimension, but it should be fairly easily doable on a mill with a rotary table, or a large lathe. Or if you're really slick, you could manually drill the bolt circles in two steel plates and use a ring roller to make the offset piece and weld the 3 parts together carefully.

Robox, what size tires are you going to go with?

With 34x9.50r15 Narrow Super Swampers and 3.07 and T-19 you would be 62 MPH @ 1900 RPM and 70 mph @ 2150 RPM in 4th and then you would want the 3200 rpm governor spring so you can hit 55 mph @ 2825 RPM in 3rd if you are towing something.

If you end up using the ZF, you may want to consider 3.54 gears instead of 3.07 because you'll be moving a bit fast and even the 3.73's would be ok. Although, your plan looks a lot like the way Mikel's J300 is set up which seems to work ok, although it takes a bit to get boost in top gear unless you're already truckin along at like 75 mph (which is way easier to do than you might imagine). With 3.73 and 36's I too will be geared like that, but I am going to drive around a bit before I decide which way to go - probably 4.10's.

The SAE #3 adapter pops up on here occasionally and there should be a suitable flywheel available, although some are for use with the Allison Auto (AT-545 or something like that).

You are going to have a sweet binder when you're done! I've always liked them, guess that is why I am using a bunch of parts from one :rasta:

Good Luck,
Patrick
 

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#23 ·
Thanks for all your input, guys... especially all that info from you, cumminsrover.

I have accumulated most of the parts that I will need for this swap, and made most of the decisions about how I am going to proceed.

Van made me a very good offer on a ZF 5 speed, so I am going to go with that. It has the Ford Big-Block pattern housing, so it will not be a simple bolt-up. I have decided to use the flywheel-housing-adapter that came with the 4BT, which is the Chevy TH400 adapter with the 8 degree tilt. I am going to machine a custom adapter plate to go between the flywheel housing and the ZF, which will correct for the 8 degree tilt and put the ZF on the same axis as the 4BT. This will be an odd adapter, with a jumble of tapped and through-holes. I made a template for it last night out of 1/16" aluminum plate. I am going to machine the plate from 1" aluminum plate stock, because that is what I have, and then I will fly-cut it down, or fly-cut the flywheel housing, or both, to get the right thickness to put the ZF output shaft into the pilot bearing. I don't have the flywheel yet, so I don't know that figure yet, but I am getting the flywheel on Tuesday.

Van generously threw in a driver's drop Dana 300. Knowing the advantages of going driver's drop in a Scout, I spent some time looking for a Waggoneer or Bronco front Dana 44. However, this proved to be difficult and expensive, and I am thrifty and impatient, so I have decided to stick with the stock passenger-side front axle. After making that decision, I purchased a divorced passenger-side NP205. I believe the 2WD ZF is short enough to make this setup work.

Luckily, I own my own fabrication and machine shop, and I am a very good machinist and fabricator. I will be doing all the work.

As for the Nissan diesel, cumminsrover is correct in recollecting that it is missing the injector pump, and according to the previous owner was in need of a rebuild anyway. Even if the Nissan was working, I would have pulled it anyway. I am a Cummins fan, and have been mentally gearing up to put a 4BT in a Scout for a few years now. The SD33T and wide-ratio T19 and Dana 300 are just sitting outside now.

As for tire size and differential gearing, I have been playing around with an online ratio calculator quite a lot lately. I will probably go with 33 inch tires and stick with the 3.73 gears for now. If I had 3.54s sitting around I would probably go with them, but... I have the 3.73s in the diffs now, and some 3.07s that I purchased a while ago back when I thought I would be going with the close-ratio T19. I just don't want to spend the money on another set of gears right now, after having bought 3.07s that I probably won't even use.

With the 3.73s and 33 inch tires, I will be at 1876 RPM @ 65MPH, and 2020 RPM @ 70MPH. This seems like a good enough place to start, especially since I have a little problem with speeding tickets!
 
#27 ·
It is a bit higher than an SD33T, like 4-5" or so and requires some lift. A SOA conversion is perfect, except that you need to fix the caster at that point. I should have measured when I had both motors in my garage at the same time.... The SD33T is a nice motor and a fairly fresh one will get a Land Rover 109 3-Door Hard top on 33's and 3.92's to about 85 MPH. A nearly clapped out one will get you to about 70. And those speeds were the same with or without towing a SAAB 900 on a dolly.

Robox, it sounds like you have a good plan of attack for your transmission. Hopefully you can get some dowel pins properly located and can fly cut off the correct amount off of the flywheel housing to be able to use the Ford flywheel. Everything about you plan sounds like it should work and that you have enough spare time to use to make the parts instead of throwing money at it.

As long as you can get enough clearance between the NP205 and the frame for the exhaust you'll be in good shape. Perhaps if the shaft between the ZF and the NP is long enough you can squeeze the exhaust through to the other side of the frame there?
 
#28 ·
At some point not too long ago, I said that I would use this thread to post a lot of pictures of the Scout build. Well, here I go...

The last week or so have been consumed with the challenges of mating a big-block ZF S5-42 with an 8-degree tilt Chevy flywheel housing. Without actually having the flywheel in my possession, I could not determine the thickness of the adapter that I would have to machine, or how much I might have to machine off the flywheel housing to get the tranny input shaft to sit nicely in the pilot bearing... but I COULD design the shape of the adapter. I first made a template. In this picture you can see the template in the background, with the 1-inch aluminum plate stock for the adapter roughed out on the bandsaw in the foreground.



With the adapter having been cut out, I took it over to the mill and got it on the rotary table. There were many machining operations from start to finish... at the point of this picture I have finish-cut the outside profile and drilled and counter-bored most of the holes...



A day or so later, the adapter was basically done. Here it is in a test-fit on the engine. You can see very clearly the 8-degree tilt being corrected with the new adapter. The big square "ear" on the left of the adapter is a mounting surface for some kind of slave-cylinder bracket, as the slave bracket on my ZF five-speed got broken off at some point...

 
#29 ·
In the meantime, I had received the flywheel in the mail, and been able to do some calculations about the thicknesses of the adapter and the flywheel housing. To get the ZF input shaft into the pilot bearing (without accounting for the thickness of the adapter!) I would have needed to take about .500" off the flywheel housing. I figured the minimum thickness of the adapter that I could get away with was .600", considering it has to have Allen-head bolts counter-sunk within it. Adding these together, I would have had to take 1.100" off the flywheel housing... which seemed like too much.. possibly giving me some problems with the dowel-pins dislodging from the aluminum casting. So, I decided to put a spacer behind the flywheel to push it back towards the ZF a little. I had a ready-made piece to start with.. the flexplate adapter. I machined the nose off of it, and made a step in the edge to mimic the step found on the back of the flywheel which locates it on the back face of the crankshaft. I was exceedingly careful to get the spacer just right... it is within .0005" in all axes... Here you can see the spacer on the back of the flywheel...



Now, however.. I need to find flywheel bolts that are .500" longer. Anyone have any ideas where to source these?

Adding this spacer, which is .510" thick, makes it so that I only have to remove about .590" off the flywheel housing... which is good. However, I do now also need to machine the area for the starter about .510" deeper. That is what is going on in this picture...



I am heading back to the shop after I finish this post to continue working on the flywheel housing. I should be able to do a test-fit of the transmission onto the engine by the end of the day. I will post pictures of that. It sure is a lot of work when compared to a bolt-up (like I could have done with a small-block pattern ZF.... but hey, when you have more time and tools than money, I guess this is what you do... I like a challenge anyway)

Meanwhile, my table is a mess of axles... I am doing a spring-over-axle, and I tore them apart a while ago, only to realize I would have to get the engine/trans/t-case into the truck before I could properly gauge the angles for the driveshafts. So here they sit....



Today is more-or-less the last day I will be able to work on the Scout for about 5 weeks, as I am leaving the country for work... (www.handofman.blogspot.com) I will miss the Scout!
 
#33 ·
Now, however.. I need to find flywheel bolts that are .500" longer. Anyone have any ideas where to source these?
Excellent lookin' progress so far.:D

I'd give ARP a scream (no, not literally:rasta: ) they must have a short headed bolt that is the right size (and being ARP you don't have to worry about it being strong enough).

http://www.arp-bolts.com/Contact/Contact.html

Order Desk & Technical Support: 800.826.3045 or 805.339.2200, fax: 805.650.0742

info@arpfasteners.com <info@arpfasteners.com>
 
#31 · (Edited)
OK... so I went back to the shop. First thing was to finish facing down the flywheel housing... IN this pic I am done with the mill work and the only thing remaining is to shorten the dowel pins, which I did with a grinder and cutoff wheel...



Pretty soon after that it was time for a test-fit........

And I am happy to say it fit perfectly! ZF shaft went into the pilot bearing perfectly, and the bolts all lined up!



 
#32 ·
OK, I really don't like you. Your toys are better than mine.

Seriously, that is a hell of a good deal. Shows what can be accomplished with a bit of willpower, a bit of intuition, and unfortunately, the right tools for the job. Makes me want to run out and buy a bridgeport.

Keep up the good work.
 
#34 ·
Back from my trip, back to the Scout.

Does anybody have an opinion one way or the other about whether off-the-shelf grade 8 bolts from NAPA would be strong enough to use as flywheel bolts?

I need a set of flywheel bolts that are about .600" longer than Cummins stock bolts....

Christian
 
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