Lightweight Diesel engine swap?

[John_parkeriv]

Hey Y'all,

Been messing with a 351W swap into my '66 for the better part of 2 years now and finally have it running decently well (at least around my street). Do still have problems on and off again with the EFI setup and a couple other little things, but she's good enough to run. Went in to fill up my daily and realized that diesels only about $0.15 more per gallon than 87. Diesel is considerably cheaper than 93 here, and of course; my bronco needs 93 or ethanol free to run without pinging. I thought about the fact that my F250 with the 6.9 will run on waste motor / fry oil. Even without that, it's almost cheaper to drive that than my Honda. So that got me thinking about throwing a small diesel engine in my bronco.

Yeah, I know. I just got it running right, why pull it out and start over again? I've got about 250 gallons of waste oil around my property, namely for the F250; and I have a near limitless supply from here around my town. Do y'all think it'd be worth putting a small diesel in my bronco and selling the 351 or just keep the current setup? If swap, which engines?

I know a lot of J**p guys run 4BT's, so that might be a decent option aside from the price. Also heard about these aluminum boat engines called a Yanmar. Any feedback is appreciated. Pictures/videos from the guys that have done it are worth extra points!

Thanks,
John

 

[Timmy390]

https://classicbroncos.com/forums/threads/engine-swap-cummins-r2-8.292345/

Tim

 

[John_parkeriv]

https://classicbroncos.com/forums/threads/engine-swap-cummins-r2-8.292345/

Tim

Looks like a good drop-in solution, but my pockets don't run that deep!

I'm also not sure how well an engine that new would run on WMO, but a good read and idea non the less.
Thanks!

 

[okie4570]

I was just looking a 4x4 6.9l drivetrain today to see if it could/would work actually. Go ride in a 4BT diesel swap before you commit, for whatever reason it's so dang loud in the cab. I've been around more than one, and as much pro diesel person as I am, I'd never have a 4BT in an early bronco. Personally I'd just keep the 351 lol.

 

[John_parkeriv]

I was just looking a 4x4 6.9l drivetrain today to see if it could/would work actually. Go ride in a 4BT diesel swap before you commit, for whatever reason it's so dang loud in the cab. I've been around more than one, and as much pro diesel person as I am, I'd never have a 4BT in an early bronco. Personally I'd just keep the 351 lol.

Yeah, that's one of my only real concerns with the 4BT is vibration. Diesels naturally rattle and so do 4 bangers. Put them together and it's like driving a blender! I'd honestly love to slap a 6.9 in the Bronco too, but the size and weight would likely make it not worth it.

 

[Broncobowsher]

There isn't really anything that really fits the needs. The 4BT is big, heavy, shaky. R2.8 is really good in the specs department, but the price tag isn't great. Really it isn't that bad for all that you get. Try and get any other NEW (not junkyard) engine and you are looking to spend even more. The small lightweight diesels, like a VW, do exist. But lack the inherent power needed. Yes, they can be built for great peak power, but they won't last making that power on a continuous basis. The big IH V8s have been done before. 7.3 powerstroke, 6.0 powerstroke, and I believe an IDI has even been stuffed under the hood in the past. These projects turn into a flash headline of "it has been done" then fall off the face of the earth.

 

[Qumanchew]

Lightweight is going to be hard to come by, but other than that an Isuzu 4bd1t checks all your other boxes. They are cheap and easy to find, came in GMC and Isuzu box trucks. Considerably smoother and quieter than the Cummins equivalent. You can run 25 percent waste oil no problem, you can run more, just a bit more involved.

 

[56f100bbw]

Lightweight is going to be hard to come by, but other than that an Isuzu 4bd1t checks all your other boxes. They are cheap and easy to find, came in GMC and Isuzu box trucks. Considerably smoother and quieter than the Cummins equivalent. You can run 25 percent waste oil no problem, you can run more, just a bit more involved.

Very clean install nice

 

[John_parkeriv]

Lightweight is going to be hard to come by, but other than that an Isuzu 4bd1t checks all your other boxes. They are cheap and easy to find, came in GMC and Isuzu box trucks. Considerably smoother and quieter than the Cummins equivalent. You can run 25 percent waste oil no problem, you can run more, just a bit more involved.

That thing looks sick! What kind of trans/transfer case setup do you run in a rig like this? I don't reckon an engine in a box truck has very many 4x4 compatible components

 

[Qumanchew]

Thanks guys! I'm running a 4r100 with an np205. A buddy of mine helped me make an adapter plate to mate the 4r100. The donor truck had a nice 5 speed stick shift that I would have liked to use, but the Broncos is my wife's, and her only request was an automatic. Now that it's done I'm happy with the auto. Everything fit in there pretty good. It didn't even needs body lift. Pumpkin to oil pan clearance was the biggest issue so to full width axles to move the pumpkin over a couple inches.

 

[.94 OR]

Thanks guys! I'm running a 4r100 with an np205. A buddy of mine helped me make an adapter plate to mate the 4r100. The donor truck had a nice 5 speed stick shift that I would have liked to use, but the Broncos is my wife's, and her only request was an automatic. Now that it's done I'm happy with the auto. Everything fit in there pretty good. It didn't even needs body lift. Pumpkin to oil pan clearance was the biggest issue so to full width axles to move the pumpkin over a couple inches.

Driving report with this engine?
Fuel mileage?

 

[79INA69]

That is a very clean install! Can you post a video of it running / driving?

 

[John_parkeriv]

Thanks guys! I'm running a 4r100 with an np205. A buddy of mine helped me make an adapter plate to mate the 4r100. The donor truck had a nice 5 speed stick shift that I would have liked to use, but the Broncos is my wife's, and her only request was an automatic. Now that it's done I'm happy with the auto. Everything fit in there pretty good. It didn't even needs body lift. Pumpkin to oil pan clearance was the biggest issue so to full width axles to move the pumpkin over a couple inches. View attachment 904039 View attachment 904040

Out of curiosity would a Lift have cured the oil pan clearance? I've got 2" body and 3.5" suspension on my setup. Also, what 5 speed was it if you know? May need to go boneyard hunting

 

[Qumanchew]

Driving report with this engine?
Fuel mileage?

When the engine was bone stock I would compare it to driving a stock V8 Bronco. Power was adequate, It had no problem maintaining 65-70mph on the highway, but also there wasn't much fun factor. With the turbo that's on it now and the fuel turned up a bit it's fun to drive. Don't get me wrong, it's not a race car, it's not a coyote swap.

Fuel mileage is averaging 19-20 around town, back roads . Highway is 23-24. Those are real numbers. My speedometer is right on and I've logged almost every tank since it's been on the road, which is almost 12k miles now.

 

[Qumanchew]

That is a very clean install! Can you post a video of it running / driving?

I've never posted a video. I'll try to take one this weekend.

 

[Qumanchew]

Out of curiosity would a Lift have cured the oil pan clearance? I've got 2" body and 3.5" suspension on my setup. Also, what 5 speed was it if you know? May need to go boneyard hunting

Absolutely, more lift would have helped a lot. I'm at about 2.5". I have no idea what the 5 speed was. It was the factory trans from the Isuzu donor truck. When I first started the build, 7 or 8 years ago there were a few companies making ford or Chevy adapter plates. I habe no idea if they are still in business. There used to be a good bit of info on 4btswaps website, but I was on there a year ago and it was dead.

 

[Steve83]

...a 351W swap...needs 93 or ethanol free to run without pinging.

It shouldn't. It should run best on 87 - that's what it was engineered to run best on. I'd just fix the pinging.

(click this text)

 

[Tricky Dick]

Thanks guys! I'm running a 4r100 with an np205. A buddy of mine helped me make an adapter plate to mate the 4r100. The donor truck had a nice 5 speed stick shift that I would have liked to use, but the Broncos is my wife's, and her only request was an automatic. Now that it's done I'm happy with the auto. Everything fit in there pretty good. It didn't even needs body lift. Pumpkin to oil pan clearance was the biggest issue so to full width axles to move the pumpkin over a couple inches. View attachment 904039 View attachment 904040

That looks fantastic. I was very close on doing this engine, I have it, a couple spare blocks, a SBF adapter, ZF5 all ready to go.

 

[hucktruck]

User Merlin76 did a 4BT swap in his 70. Pics in his gallery

 

[73azbronco]

I was just looking a 4x4 6.9l drivetrain today to see if it could/would work actually. Go ride in a 4BT diesel swap before you commit, for whatever reason it's so dang loud in the cab. I've been around more than one, and as much pro diesel person as I am, I'd never have a 4BT in an early bronco. Personally I'd just keep the 351 lol.

I have an 06 duramax LBZ, I have to turn it off if I use the drive through to make an order, and I have stock exhaust. But it sounds great.