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Discussion Starter · #1 ·
Alright, this is gonna be a long one, so here goes...

Ive had this truck since I was 17, traded a farmall H for it actually. My grandfather and I got it running and moving under its own power and through the years Ive made more and more improvements to it. I rebuilt all the brakes, did some valve work and threw on a new head gasket, dropped some serious dollars on brand new tires for it and a whole host of random other miscellaneous things to be sure. That leads us to today... its been a great truck and realistically has never let me down, though ive never actually used it for the reason it was built: Work. That is about to change...
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Ive come into own a rather cherry early 12 valve cummins out of a d250 or 350, not real sure which. It was an auto truck and had around... 113k on it i think when they ripped the engine out. It sat for a number of years before I got my mitts on it and started to get it running again. Luckily that turned out to be pretty easy. next on the list for my conversion was needing a bellhousing to bolt a medium duty 5 speed to the 12 valve which actually happened to be also easy... found one on marketplace for a steal and snagged that pretty damn quick.
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I already had a transmission that i wanted to use but sadly it wasnt the one i thought it was as the shift knob had been changed over the years and lead me to believe it was a 5th over rather then a 5th direct... but it is a 5th direct. This was in a 70/80s GMC c6500 with a tall deck 427... so out came the torch...
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now to liberate the big block and clark 5 speed...

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I dont have any pictures of the trans and 427 split apart but here is where Im running into issues. I need to find a clutch/flywheel assembly to put this all together and have no idea where to even start. I called up Quality Bus and Truck parts in Big Lake MN but they havent gotten back to me yet so im stumped...

Now Im onto other issues in the meantime... namely how wide the 5.9 is with the factory manifold, so I needed to do away with that. Id seen that 3rd gen dodges had the turbo placed between the 4th and 5th cylinders and that also faced it straight down, which was going to work perfectly... so I found one, or rather a guy found me and I bought that and the front pedestal mount off him for reasonable money...
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I still need to find/create the correctly orientated oil drain for the turbo and get the correct exhaust bolts but its looking like how I envisioned it would anyway.

Ive been thinking on what kind of intercooler setup, if any, I want to run. My first thought was an Air to Air setup like out of a regular pickup but I highly doubt that was gonna fit correctly and Id have to run massive, un wildly intercooler piping all over the engine bay... lots of money in fittings and piping and it would still look like a mess. After cruising through a parts house website i cam across a factory aftercooler that looked extremely promising...

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Ive not bought it yet of course but just planning everything out in my mind. Im wondering where id happen upon the injector lines Id need for this setup as the factory non-intercooled ones certainly will not work, much to my dismay.

That pretty much leads us up to today. I measured out the truck to see just how much butchering Im going to have to do to make everything fit and after doing so I feel mildly unsettled... unless my tape measure is faulty or I cant read, it looks like it could drop in with very, very little modification... even using the stock transmission/bellhousing mounts and the front pedestal mount. Once i have the whole original powertrain ripped out we will see how easy its going to be though...
 

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I already had a transmission that i wanted to use but sadly it wasnt the one i thought it was as the shift knob had been changed over the years and lead me to believe it was a 5th over rather then a 5th direct... but it is a 5th direct.


> This is going to give you a 1948 top speed - Might not be such a bad idea, since you have 1948 brakes.
I dont have any pictures of the trans and 427 split apart but here is where Im running into issues. I need to find a clutch/flywheel assembly to put this all together and have no idea where to even start. I called up Quality Bus and Truck parts in Big Lake MN but they havent gotten back to me yet so im stumped...
> Check the existing Chevy bellhousing, it might be SAE.
file:///C:/Users/mclea/AppData/Local/Temp/HOW%20TO%20DETERMINE%20WHAT%20SAE%20HOUSING%20YOU%20HAVE.pdf

I still need to find/create the correctly orientated oil drain for the turbo and get the correct exhaust bolts but its looking like how I envisioned it would anyway.


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> Picture from my notes (many years ago). The hot and cold sides of the turbo are unlocked, the cold side is rotated to make the turbo drain point straight down.
Ive been thinking on what kind of intercooler setup, if any, I want to run. My first thought was an Air to Air setup like out of a regular pickup but I highly doubt that was gonna fit correctly and Id have to run massive, un wildly intercooler piping all over the engine bay... lots of money in fittings and piping and it would still look like a mess. After cruising through a parts house website i cam across a factory aftercooler that looked extremely promising...

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Ive not bought it yet of course but just planning everything out in my mind. Im wondering where id happen upon the injector lines Id need for this setup as the factory non-intercooled ones certainly will not work, much to my dismay.

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> My 1986 Ford F150 - the choice is installing lots of hose or buying a new set of injector lines (might be difficult to find for the 6bt). I don't gave a good opinion.
> Note: if you go the intercooler route, think about the narrow nose on that Federal - consider running the hoses out of the top and/or bottom.
Russ
 

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Discussion Starter · #3 ·
The brakes will do just fine regardless of the speed I am going... big drums, nothing different in comparison to newer style drums in all reality. The bellhousing is indeed an SAE2 but I need to figure out the flywheel and pressure plate.

As far as the turbo goes I know you can clock everything, I just need to get the right drain.
 

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The water aftercooler is the way to go for old trucks. You can always plumb it to a heat exchanger in front of the radiator for more cooling. You need new injector lines though to clear it. Yeah - your brakes will be fine if in good shape! Drum brakes are on most semi trucks all the way around.

Here is a huge load on a 33 Ford with mechanical brakes I hauled over the coastal mountains. Also I haul loads with my 35 ford all the time...
 

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I have a picture of a Federal just like yours with a DT466 I took in the late 80's. I'll try and find it and post it. The DT466 was not as good a fit as the 5.9 will be...
 

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In my ‘37 GMC I put the i’cooler vertically behind the grille, with the piping in and out the bottom, there is plenty of room there in the GMC, might that work for you? Look carefully in the picture can see
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the i’cooler behind the grille.

Ed in CO
 

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That exhaust manifold was common on 6bt's used in Ford medium duty trucks in the '90s. Just to double check is the part # on the manifold 3931744? If so here is the parts list as shown in photo #1 below.

1 3819725 Hose Clamp 9/16x1-3/8 (2 req)
3 3900630 M8x1.25x20 Flange Head Bolt (2 req)
5 3931973 Oil Drain Tube
6 3931970 Hose
7 3931350 Oil Drain Gasket
8 3916348 Turbo Oil Drain
13 3931824 O Ring Seal

Now for the aftercooler. We don't see that 6bt unit all that often but they were used. You will need special injection lines that match you pump which should a a Bosch VE. So far I haven't found one to get you part numbers. I've found marine and road engines with the P pump, industrial engines with a Lucas pump, and there were generators with the aftercooler. Also, there are at least 3 different designs of those aftercoolers. The one you show is the more common one. There are quite a few more parts to that puzzle too. Fittings and hoses to connect it into the engine cooling system. You also need a fair sized radiator. A 6bt will run quite a bit hotter than that old gas engine. Below is a photo of a VE pump engine with that aftercooler. I've found an ESN for one of those 44495303. So here we go. 1st will be the coolant plumbing shown in photo #3 below. There is a fitting that attaches to the head shown in photo #5 below.

1 210753 9/16x1-1/4 Hose Clamp (6 req)
2 3918608 Elbow Hose
3 3918607 Molded Hose
4 5337075 Hose Coupling
5 3907168 Tube
6 3918611 Hose
15 3905639 Tube on Head diagram

Now for the injection lines shown in photo #4. Some of the clamps may be reusable from the existing lines but I listed them anyway just in case.

4 3918109 M8x1.25x25 Flange Head Bolt (2 req)
5 3907814 #4 Injection Line
6 3907815 #5 Injection Line
7 3907816 #6 Injection Line
8 3917712 M5x.080x22 Hex Cap Screw (6 req)
9 3903723 5mm Plain Washer (6 req)
10 3904519 Tube Brace (3 req)
11 3917747 Tube Isolator (6 req)
12 3917778 Tube Brace
13 3917777 Tube Brace (2 req)
19 3915419 #1 Injection Line
20 3915420 #2 Injection Line
21 3915421 #3 Injection Line
23 3911668 M6x1.00x10 Hex Cap Screw
24 3916417 Vibration Isolator
25 3916418 Tube Brace
26 3916420 Tube Brace

Now for the last of the aftercooler parts there is an air inlet and a few misc items. You will have design your own air tube from the turbo since none came in that low position.

5 3914029 Manifold Gasket
7 3933334 Air Crossover Connection
8 3914856 Gasket
9 3900631 M8x1.25x25 Flange head Bolt (4 req)
14 3909394 Drain Cock
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Another thing you mentioned is the SAE2 flywheel adapter and clutch assembly. There are 3 different starter locations for those adapters. They came with the starter high and middle on the passenger's side and middle on the driver's side. You'll probably need the driver's side on since you turbo is in that position on the passenger's side. Units also came in either aluminum or cast iron. The SAE2 housing with the starter on the driver's side is part 3931713. I believe the SAE2 flywheel is 3921763 and you'll need 8 bolts and washers which are parts 3901395 and 3900269. Starter may be a Delco 8200289 39MT. You'd have to find the clutch that matches the splines on your transmission. The flywheel is for a 14".
Here ends the sermon for today. LOL. Hope I didn't transpose any numbers in those parts. This took a bit of digging.
 

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Discussion Starter · #8 ·
Alright, lets go...

Man, thats allot of information to look through! I really appreciate you going through the trouble of tracking all this stuff down! Now I got some stuff to go off of to get this all done.

I havent checked to see what the part number is on the manifold but Im reasonably sure thats the one it is.
As for the aftercooler I was planning on running it as a stand alone unit with its own 12 volt electric pump to circulate the coolant to keep everything nice and chilly. With any luck it will work reasonably well.

The injector lines are a big help! Now I just need to find a place to purchase them and hopefully not go completely broke in the process. I looked one up and had to sit down after looking at the 80 dollar price tag for the one line, man... this diesel stuff aint cheap.

I think the factory copper/ radiator should do me pretty well. its around 2.5 to 3 inches thick and pretty tall but if it ends up getting to toasty ill have to opt for getting a rad made to keep it cooler.

The bellhousing Ive got has the starter mounted really low on the passenger side under the turbo so it should clear pretty well. I dont have a starter on hand to check it but after looking through a few photos it seems to be what a few of them have used through out the years. Fingers crossed though...

Ill keep re-reading through your post though so i might be asking a few more questions. haha, again, much appreciated for your time!
 

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No, those injection lines are not cheap, Might check this company. They show 3907814 for $38.46 which is really cheap. Around $60 is more average. Just have to do some web browsing to find the best deal. Are you planning a separate radiator for the aftercooler? If so, it needs to be in front of the engine cooling one. The flywheel adapter you have is probably 3931716 which is basically the same as 3931713 only on the passenger's side. Of course it uses a different starter but the flywheel doesn't change. OEM CUMMINS 3907814 TUBE-3907814
 

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Discussion Starter · #10 ·
Alright, since I got some time after work to look at this a bit, here is the bellhousing I have. The starter location should give me plenty of space between the turbo and starter, that is if my Mk1 eyeball has anything to say about it. The bell housing is currently bolted to the doner trans which is a clark 282 vhd trans out of that GMC C6500. 5th gear comes out to being direct in this instance so I need to find a rear end to replace mine with a radio of around 3.73 or so which would give me a cruising RPM of 2300 at 70mph. The idea here is to find a 2 speed, dayton hubbed, drum braked axle to swap in so I dont have to change a ton of stuff.
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Here is the pressure plate off the big block 427 to match the clark 282 trans. Its weird for a medium duty being that it has a more light duty style throw out fork and is a pusher style rather then what seemed to be more common, the puller style clutch. Im thinking if I can find the flywheel for the cummins either A: the bolt holes for this plate may already be in it, or B: Bring it to work and drill the pattern in it for this pressure plate. I could just build a whole new clutch from scratch if I really wanted but Im not so sure i want to drop that kind of money on a steel blank at this time (still is WAY up from normal...).

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Here is the home the clark will soon find itself in. With preliminary measurements it looks like it should fit in rather nicely with out coming in contact with the pedal assembly on the driver side so I shouldnt have to mess with relocating the brake master or the clutch pedals. Ive thought about maybe using the factory clark 5 speed that its equipped with since I could go with a lower geared rear end since its over driven in 5th (but man the split between 3rd and 4th is insane). After looking between the two clarks it wouldnt surprise me if the front plate from the other clark bolted right onto this one...

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Yes, that SAE2 style housing will probably clear the turbo. The other style housing looks like the one in the photo below would be a problem. If that clutch assembly was in an SAE2 housing, it may bolt up to the Cummins flywheel. SAE is a standard. Drilling the flywheel can be an option. Need to make sure the pilot bearing in the flywheel matches the transmission too. You mention a cruising speed of 2300 RPM. The engine is capable of that but your fuel mileage will really suck. These Cummins like to operate in the 1700-2000 RPM range. 1800 RPM is a number often used. These engines hit their peak torque in the 1700-1800 RPM area. Might need to think on adding an auxiliary transmission with an OD gear in addition to your 3.73 gear. Then you'd have the fun of 2 shift levers and 15 gears. Most auxiliaries had and OD gear, 1:1 gear, and an under drive gear. The older ones are often called Brownies because that company made them in the early day was Brown-Lipe. There are units from Spicer, Eaton, and others out there. They were often found in 1.5 ton and up trucks. There are even 4 speed models. Do you know what rear axle you have in the truck now?
 

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Discussion Starter · #12 ·
Yes, that SAE2 style housing will probably clear the turbo. The other style housing looks like the one in the photo below would be a problem. If that clutch assembly was in an SAE2 housing, it may bolt up to the Cummins flywheel. SAE is a standard. Drilling the flywheel can be an option. Need to make sure the pilot bearing in the flywheel matches the transmission too. You mention a cruising speed of 2300 RPM. The engine is capable of that but your fuel mileage will really suck. These Cummins like to operate in the 1700-2000 RPM range. 1800 RPM is a number often used. These engines hit their peak torque in the 1700-1800 RPM area. Might need to think on adding an auxiliary transmission with an OD gear in addition to your 3.73 gear. Then you'd have the fun of 2 shift levers and 15 gears. Most auxiliaries had and OD gear, 1:1 gear, and an under drive gear. The older ones are often called Brownies because that company made them in the early day was Brown-Lipe. There are units from Spicer, Eaton, and others out there. They were often found in 1.5 ton and up trucks. There are even 4 speed models. Do you know what rear axle you have in the truck now?
I thought about using a brownie but after looking at the prices for anything aux-box related I damn near fainted. They are asking some pretty rediculious prices for that stuff.

The current rear is a timken h100dph with a 7.2 final ratio... so it's absolutely terrible for everything haha
 

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6000 or 7000 series Brownies would suite your truck just fine, but still need to do something about that 7.2 axle ratio. Brownies are often overlooked by people who know nothing about them. Must search for yourself, look for units in abandoned vehicles, search cab for another shift knob, look behind cab for two shift rods. Don’t bother asking, they either won’t know what you are talking about or don’t know what is in their yard.

Many Brownies came with Tru-stop disc brakes on the back end, but with the advent of ‘spring brakes’ many disabled their units. If you find one with a working brake, that is a bonus. Found ones usually sell for 600 or 700 dollars, broken ones are rare.

good luck.

Ed in CO
 

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No, Brownies aren't cheap. Now, you might scrounge around some salvage yards with big trucks and find one you can buy reasonable. Have to be careful because not all of them have OD gears. These things were used form about the 1920's on. $1500-2000 can be very common price range. We have a few members that may have one for sale. You have a 7.20 rear ratio. Be good for hauling around a house. Dang that's low. I don't find any reference to that part number.
 

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Discussion Starter · #15 ·
6000 or 7000 series Brownies would suite your truck just fine, but still need to do something about that 7.2 axle ratio. Brownies are often overlooked by people who know nothing about them. Must search for yourself, look for units in abandoned vehicles, search cab for another shift knob, look behind cab for two shift rods. Don’t bother asking, they either won’t know what you are talking about or don’t know what is in their yard.

Many Brownies came with Tru-stop disc brakes on the back end, but with the advent of ‘spring brakes’ many disabled their units. If you find one with a working brake, that is a bonus. Found ones usually sell for 600 or 700 dollars, broken ones are rare.

good luck.

Ed in CO
No, Brownies aren't cheap. Now, you might scrounge around some salvage yards with big trucks and find one you can buy reasonable. Have to be careful because not all of them have OD gears. These things were used form about the 1920's on. $1500-2000 can be very common price range. We have a few members that may have one for sale. You have a 7.20 rear ratio. Be good for hauling around a house. Dang that's low. I don't find any reference to that part number.

In my planning stages i looked over the brownies and had some ideas for what I wanted to do to get it to work but the issue was finding one and then making everyting work the way I wanted. I also looked into a gear vendors OD but when i called the guy to bounce some ideas off him he got all sorts of weird and said the cummins is a 6 cylinder, it wont have the power to pull double over drive., even after i had all the numbers sorted out in my head on how I thought it would work but i just wanted some confirmation. Kinda wrote them out of the whole process after that, little sour of an experience.

This rear end had another option for a ring and pinion ratio which was 5.8... still not great but was certainly better.
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The guy knocking the 6 cylinder Cummins hasn't got a clue. With some minor upgrades and tuning the one you have can put out 300 HP and gobs of torque. I'd change the turbo to a WH1C or HX35W. Those are essentially the same turbo. A second turbo option could be an HE351cw. Put a 3200 RPM governor spring in the injection pump, do a few adjustments to fuel and timing, and you're there. Don't need fancy injectors but might have those checked to be sure they are in good order. That would be 3 times the power the old flat head 6 had. On the rear end, you'll probably need to change that to something a bit more modern to get the gear ratio. Have to look and see what's out there that has the higher gear ratios and can keep the same wheel/hub design. Don't want to lose that antique look if possible.
 

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It might be worth your effort to look for another rear axle with the same wheel bolt pattern with proper ratios and matching brake system. Save a lot of effort in transmissions, etc.

Ed in CO
 

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Ed, the problem there is I believe this truck has the Dayton steel spoke hubs so there's no bolt pattern. The Budd 6 stud hubs were an option. Going to take some research to get a HD truck axle in the low 3's. Most anything modern may have air brakes. That truck has a GVR of 19,000 lbs. Medium duty truck axles have ratios ranging from 2.69 to 7.17. If he can find an axle in 3.73 and add a Brownie with a .85 OD that would be around 1955 RPM @ 70 MPH. Very good speed for a 6bt. It would be around 1680 @ 60 MPH which is still good.. Probably drop back to 1:1 as got too much lower. Might still be OK @ 55 MPH depending on load.
 

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I know it has Dayton wheels, there are lots of box trucks around with Dayton’s, getting hydraulic brakes wold be less common.

Ed in CO
 
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