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F250 4BT Buildup

50K views 72 replies 26 participants last post by  wfduggan 
#1 · (Edited)
It is about 35 miles to my work. With the increasing cost of fuel and with our economy getting more like Europe, I needed to change my long-range plans for a commuter vehicle. The area I live in has a lot of deer accidents and first-time adult drivers. To reach my goal of a 30-mpg vehicle that was safe for my five-person family, I decided to put a 4-cylinder diesel in a full-size pickup. I started this project in 2006. The original idea was to put a naturally aspirated Perkins 4.236 into a 1985 F250 Crew Cab. The Perkins was too tall to fit without a body lift kit. That was something I didn’t want to do. I have young children who would have a hard time getting in and out of the truck. I did some research and decided that a Cummins 4BT would fit my needs. I’ve had a soft spot for Cummins engines since my years in college, so that made the change a little easier. A friend sold the Perkins for me and I kept saving money until I had enough to buy a 4BT. While waiting, I found another 1985 F250 that didn’t need as much bodywork and paint. I got the other truck and a 4BT around January 2007. There were about 20 4BTs at the place that I got mine (Adelman’s Truck Parts, Canton, OH). I got a small education on some of the different options. I chose a CPL858 with a gear-driven power-steering pump, a Ford belt-driven vacuum pump, and a small-block Ford bellhousing setup. I didn’t get the T19 transmission that was mounted to it, because I had already bought a Toploader 3-speed Overdrive for the truck and I had a diesel T-19 at home.
 
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#2 · (Edited)
January 2007. After I got the engine home, I started checking it over. I found that the flywheel and clutch were worn out. The flywheel was resurfaced and I researched until I discovered that the clutch assembly was for a 1985 F350 with a 300 six-cylinder. I found out that the pilot bearing that had come with my engine was not designed for automotive use. It had one side shielded with metal and the other side open to the elements. A pilot bearing needs to have both sides sealed (not shielded or open). I got the clutch assembly from Advanced Auto and got the pilot bearing from a skate board shop in LA, CA. I painted the engine, trans, and parts along the way. The dipstick tube was broken off flush with the block, so I chose to knock it out from the crankcase side. I had to change the oil pan gasket. That’s when the search for a competent Cummins parts person began… Because I couldn’t find a metal dipstick tube that reached up to the intake manifold, I modified a small-block Ford chrome dipstick/tube to fit in the original dipstick’s place.

http://www.4btswaps.com/forum/attachment.php?attachmentid=540&d=1178591469
 
#3 · (Edited)
March 2007. When the cold weather broke in March, I started the conversion. Before the original engine was pulled, I measured the location of the crankshaft (as a reference for where to place the 4BT). The truck had to be prepared first. This included converting the truck to air conditioning.

April 2007. I was finally trying to install the powertrain. In order to put the engine in the proper position (using the crankshaft reference measurements and the stock transmission crossmember), both frame-mounted engine brackets needed to be removed. Eventually, the engine and trans were held in with 2 x 4 blocks. I decided where to put the engine by using the original engine’s centerline, judging motor mount location, valve cover/cylinder head removal access, and exhaust routing. The transmission mount was about 3 inches further forward than where the old transmission mount had been. I fabricated a .375-inch plate that relocated the transmission mount 3 inches back. The transmission was bolted in loosely. Then I had to decide which rubber motor mounts to use! Because of a lack of availability, safety locks, or reasonable pricing, I decided to go with Chevy motor mounts. They are about $12 at AutoZone, in stock, and encapsulated (in case they break). They have been used on six-cylinders, small-block V-8s, big-block V-8s, and the 6.2/6.5L diesels for more than 25 years! Because I didn’t have a welder at home, I fabricated the mounts one plate at a time. This took about 2 weeks! The engine and transmission were finally bolted to the frame! A front driveshaft was made that was 3 inches longer. I didn’t balance it, because I wasn’t sure that this would be the final mounting/modification. After the first engine start (using jumper wires and a 6.5 gallon fuel can) the mounts settled into position. The block shifted about .250-inch toward the driver’s side and down about .125-inch. This put the left/front corner of the block too close to the frame. That area of cast iron is not essential, so I cut some of it off at a 45-degree angle (for clearance).

http://www.4btswaps.com/forum/showthread.php?t=26&page=4&highlight=mounts
 
#4 ·
May 2007. I installed a 351W two-row radiator in the truck, instead of the 6.9L diesel radiator. It is supposed to be adequate for cooling the 4BT, less bulky, upgradeable to larger capacity, and cheaper to replace. I ran the fuel lines and hooked up the wiring. Malfunctioning water temperature and oil pressure sensors had to be replaced. Wires had to be shortened or lengthened, and some wires had to be removed. I no longer needed the glow plug system! The diesel clutch master cylinder and the 4BT clutch slave cylinder were used. The 4BT power steering pump pressure hose needed to be modified, because the original Ford pressure hose wouldn’t work. The tubing on the steering box end had to be bent into shape and cut to length. A b-nut that matched the steering box was installed and the tube was double-flared again. There were many other details that needed to be done, but we don’t need to waste time with all those little details. There wasn’t an exhaust or intake cleaner system yet, but I couldn’t wait any longer! I finally drove it in the neighborhood! I have to say…I was a little disappointed. The turbo outlet was pointed toward the firewall and the pulsing of the exhaust only added to the vibration. The exhaust sounded like a John Deere 2-cylinder at idle, but it wasn’t as loud as I expected. I lugged down the engine to check the torque output. It surprised me! I expected the truck to buck or slow down, but it stayed the same speed and kept trying! After the drive around the neighborhood, I contemplated my next move.
 
#5 ·
June 2007. I decided that I wanted to swap from the straight, low-mount turbo system to a high-mount turbo system. I also wanted to change the thermostat housing from a straight-up type to a straight-forward type. I posted ads in the 4BT Forum classified ads section. I was fortunate to be able to buy an exhaust manifold (including turbo drain tube) and swap thermostat housings. Thank you Dieselcruiserhead and MCInfantry. While taking off the old exhaust manifold, the #4 cylinder exhaust bolt broke off flush with the head. I spent about 4 hours drilling and grinding before I was able to clean the old threads out. That was the longest it had ever taken me, but I got great results! After taking the old exhaust manifold off, I noticed that one of the exhaust manifold gaskets was in a D shape. I had found the 2-cylinder John Deere sound! Next task was the turbo. Re-clocking the turbo was a bear! The exhaust turbine housing was stuck, so it required a lot of PB Blaster and a lot of patience. Eventually, the hot wrench (torch) had to be used. After heating the mating surfaces, two of us pried evenly (using wedges/chisels and a pry bar) on opposite sides of the housing and it finally came loose!
 
#6 · (Edited)
July 2007. After bolting on the high-mount turbo setup and making the crossover tube, it was time for the exhaust system. Since the turbo outlet size was 2.5 inches, I chose 2.5-inch mandrel tubing for the exhaust. I wanted to keep the temperature high in the exhaust, but didn’t want to have too much restriction. According to my research, a 2.5-inch pipe should flow the amount of air necessary (without restriction). I will test it after it is on the road. I used 5 feet of tubing to the muffler and 7 feet of tubing after the muffler. The tailpipe exited in front of the right/rear tire. Flowmaster 3.0-to-2.5 inch reducer cones were used at the inlet and outlet of the round 3-inch DynoMax UltraFlow muffler. From inside the truck, the exhaust was quieter than the engine! I drove around the neighborhood some more. The engine sounded better, but there was a droning through the body of the truck. I removed one of the three exhaust hangers and it got rid of the droning.
 

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#7 ·
August 2007. I had driven the truck without a fan up to this point. However, I will need one when I get the A/C working. I already had a Taurus SHO single-speed electric fan. There were a lot of websites stating that this was the electric fan to use (or the two-speed version of it). It was installed in the stock fan shroud. If that isn’t good enough, it will be changed in the future. It was wired with a Bosch 75-amp relay, the stock 4BT fan switch (probably a Dodge unit), and a bypass toggle switch. I also installed Autometer Z-series EGT and boost gauges.
 
#8 · (Edited)
September 2007. Next came the air cleaner system. I had bought a Summit 6 x 9 cone filter, and chose to mount it on the driver’s side. It was bulky and I didn’t like the looks of it. I decided to move the battery to the driver’s side so I would have a cleaner look. The air cleaner system was redesigned to sit where the battery had been (on the passenger side). That was much better! I finally got license plates and decided to take it to the fuel station. I didn’t go far before experiencing problems that needed to be dealt with! The gear spread from second gear to third gear was too wide and there was a bad vibration above 40 mph. The brakes were dragging too. I had to clean the front caliper slides, replace the pads, and turn the rotors. The right emergency brake cable wasn’t returning either, so that was fixed. I could have chosen to get the 3200-rpm governor spring to overcome the wide gear spread, but I thought that it would only be a patch for bad gearing. I chose to change the transmission. First gear had seemed a little too high before, so I needed to confirm the gearing. First gear was around the 3.29 advertised for the transmission and the rear end ratio was 3.73. I had thought that the rear end ratio was 3.54! One of my parts trucks had a good 3.54 rear end, so it was added to the “to do” list.
 
#9 · (Edited)
October 2007. After doing some research, I decided to get a Ford M5R2 transmission from an F150. I found one for sale ($200) on the Columbus, Ohio Craig’s List. The owner guaranteed smooth shifting, etc. Road trip! After getting it home, I replaced the throw-out bearing, shift tower bushings, and shift rail seals. The transmission was installed, which required the crossmember to be moved, and the driveshaft was checked for length. The driveshaft was the correct length, so it was sent out for new u-joints, center bearing, and a balancing. After it was put together, I drove the truck some more and noticed that the 3.73 rear end was not going to make it much longer. The transmission output seal was also leaking.

http://www.4btswaps.com/forum/showthread.php?t=1838&highlight=m5r2
 
#10 · (Edited)
November 2007. After much searching, I located a transmission output seal. However, I had troubles with the slip yoke and the new seal. After getting another seal and repairing the slip yoke, the transmission no longer leaked. I made a custom alternator-mounting bracket which mounted between the water inlet housing and the engine block. After the initial mock-up, I lowered the mount boltholes an additional .500-inch. I then mounted a Motorcraft 1G alternator, because it is smaller than the original HD Motorcraft alternator and it can be boosted to 120 amps. This was done to facilitate the future addition of an air conditioner bracket on the thermostat housing. A co-worker was getting rid of his 265/70R17 Goodyear ST tires. They only had 6,000 miles on them and he was selling them cheap. I decided to buy the tires and some new rims. I ordered Eagle Alloy 17 x 8 rims for the tires. There were some problems getting the correct rims too! Set backs have been a big part of this conversion! The 3.73 rear end had left-hand threads on the driver’s side. The chrome lug nuts wouldn’t work until I swapped in the 3.54 rear end. That forced me to swap the rear end right away! Of the four rear springs that I had, 3 were bad! These sets of springs had less than 70,000 miles on them, but they were more than 20 years old.
 

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#11 ·
Forgive me for posting to your build up post but I just wanted to commend you for troubles and perserverence, I too have just begun my own conversion on a 1986 F-350, I understand some of the things you have done such as changing the batt location to facilitate a better intake design. I look forward to reading further posts on your conversion, and hope to see more pics as well. Good Luck and keep up the good work! :beer:
 
#13 ·
Thank you. It has been an eventful experience so far. I have more photos and can take more. If there is anything that you would specifically like to see, I'll try to post a photo of it. If you have ideas on how I could improve something, I'm open for ideas.
 
#14 ·
How about an engine bay pic? Sounds like your experience has been similiar to mine on the swap. The engine was time consuming but straight forward, but since then there have been things come up.....some engine and some other related. I know when I get it all ironed out I will be happy, as will you. Keep on wrenchin till you get'er.
 
#16 ·
Sorry. I was out of town on a job interview. I've got some pictures from September. I'll try to get more later.
 

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#20 ·
Thank you for the compliments. I have less than 200 miles on the first full tank, so I haven't got a good fuel mileage reading yet. The truck is not much to look at yet. That will be the last part of the buildup. It still has the paint job from the company I got it from. This picture is with the new wheels and tires, but before I install the 3.54 rear end and 2 inch dearched rear springs.
 

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#21 ·
Here's a view of the exhaust clearance. There is a minimum of about 3/4-inch clearance everywhere. It's hard to tell from the photo. It would have probably been better with two 45-degree bends, but it is easier this way and it is mandrel bent.
 

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#24 ·
I did a little playing with the Paint program on my computer. This is close to what my visual goal is. It may take a while!
 

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#26 ·
Thank you for the encouragement. The rear axle swap is almost complete. I should be posting the results soon!
 
#27 · (Edited)
December 2007. Both rear axle springs got new top leaves, which were dearched 2 inches. The .375-inch jack plates were also removed from the bottom of the spring sets. A 3.54 Dana 70 rear from my F350 parts truck was swapped in. Of the 4 brake cables from 2 rear ends, 1 cable was good. It was installed into the 3.54 rear and a new cable ($23) was installed on the other side. The drums were turned and the brakes repaired of someone else’s installation errors. One of the anchor pins was loose, which only required tightening. The truck finally drove the way I had expected. A major portion of the harmonic droning was gone! First gear seems close to perfect for me. 12.27:1 was too high, 14.58:1 was too low, but 13.84:1 seems to be perfect for the engine/truck weight. I believe I need a 19-tooth speedo gear (instead of 20-tooth) to get the speedo accurate, but I’ll check that out later. I don’t know much about Dana rears. If someone on this forum knows a lot about them, I would like to learn more about their differences. I had trouble getting the proper axle nut socket. Dana 60s (which is what we have at work) have 2.375-inch axle nuts. That was too small for my rear. The D70 axle nuts are 2.5 inches with rounded corners. The parts stores carried a 2-1/2R socket (listed for a Ford front D50), but that was too small too. The 2-1/2R ($17?) didn’t even have a 2.5 inch ID. I finally ordered a 2-1/2 inch axle nut socket with pointed corners (listed for a 90s Dodge) that worked. Two part numbers for the socket are OTC #9121 and Carquest #33180 ($21). The link below helps identify some of the differences between D60s and D70s.

http://www.pirate4x4.com/tech/billavista/D70/D70.htm
 
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