Hyundai D4BF info and installation guide.

[Growlerbearnz]

Thinking of fitting a brand new Hyundai D4BF to your Delica? No? Take a look at these photos and you'll change your mind:

SO. SHINY.

The D4BF is a 4D56, made under license. It even says 4D56 on the engine block. It says "Hyundai" on a bunch of other parts, but I don't mind. Hyundai make a few different versions of the 4D56 (intercooled, electronic injection control, etc.) but the D4BF is the one that's most like ours (mechanical injection, non-intercooler) http://www.hyundaiengine.com/auto_diesel/05_d4bf.html.
Over the years Mitsubishi improved the 4D56, and the D4BF engine incorporates all the improvements and upgrades Mitsubishi ever made, and then some. The updates I've noticed are mostly to strengthen the engine so it can make more power, as the engine block is shared with the higher-output D4BH. Extra ribs on the block casting, new brackets to stop things flexing, water-cooled turbo, that kind of thing. It also has higher pressure injectors and better pistons for a more efficient burn, 3-bolt rocker cover and alloy half-moon seal to reduce oil leaks.

DETAILED PHOTOS:
(notes: alloy half-moon seal, water-cooled turbo pipes, new flywheel and clutch)

(notes: primitive alternator tensioner, no AC pulley (but drilled for it), no AC tensioner, timing belt cover with access plug for tensioner.)

(notes: water pump outlet is at a different angle, but it's not a problem. Alternator plug is different. Water cooled turbo. No AC bracket. Hyundai 75A alternator is a semi-smart unit, well worth keeping.)

(notes: Dipstick to the front. IP linkages. 12V glow plugs.)

PREPARING THE NEW ENGINE:

First, download the workshop manual.

I strongly recommend buying and fitting these new parts:
-Engine mounts MB581192, MB581191
-Radiator hoses MB356382, MB356383
-Radiator hose clamps X4 MA609112
-6V Glow plugs X4 MD092392 (The D4BF comes with 12V glow plugs).
-Heater hoses MB438044, MB438045
-Alternator oil drain hose MD141543


UNINSTALL THE OLD ENGINE
You'll need both engines side by side so you can swap parts between them.

Disconnect battery.
Remove passenger door (the wiring plug is behind the glove box), seats, engine covers.
Drain coolant and oil.
Remove radiator, fan, fan clutch (not shown in photos but it would have helped), air inlet pipes, accelerator cable, Transmission cable, fuel lines, starter, earth straps.
Unbolt air conditioner pump and power steering pump and move them aside.

Remove the lower bellhousing cover and remove the 6 bolts holding the torque converter to the flexplate. (An Allen key in the ring gear teeth works brilliantly to stop the flywheel turning)
Remove exhaust, oil cooler line banjo bolts, vacuum pipes from alternator.
Support the engine and transmission. Keep the engine crane's boom as close to the engine as possible, or the engine won't fit out the door. When I did it I had 5mm to spare. Depending on how wide the legs of your crane are, you might need to put the van on an axle stand and remove the wheel.

Remove the bellhousing to engine bolts
Undo the lower bolts on the engine mounts. In theory you could undo the top nuts, but if your engine mounts have compressed (like mine had) it's almost impossible to get a spanner in there.

(Picture stolen from teh internets.)

Protect the AC radiator, as the engine will come very close to it while removing.
Remove engine.

SWAP PARTS FROM YOUR OLD ENGINE ONTO THE NEW ONE

Swap your glow plugs over. Ideally fit brand new genuine Mitsubishi glow plugs. The D4BF comes with 12V plugs which won't work with the super-quick 6V glow system. (If your Delica has a glow plug warning light on the dashboard it's not the super-quick system, and you can probably keep the 12V Hyundai ones).

Injection pump linkages. The Hyundai ones are basic, and the idle speed adjuster is on the back of the pump where it's difficult to access. The IP has all the correct holes for mounting the Mitsubishi linkages. You may need to mix and match the bolts/spacers/washers to make it work.

The main accelerator lever is attached to the pump's shaft with splines. Read the setup instructions in the next post before you remove anything. I set the pump to idle speed, removed the Hyundai arm and installed the Mitsubishi one in the same position, more or less. This will probably need re-adjusting once the engine's installed and running: more detail on how to swap the linkages and get them aligned are in the next post.

AC Idle-increase vacuum solenoid (round can on side of IP): I found that the Hyundai one tended to stick in the "fast idle" position. Maybe mine was slightly faulty, maybe it was something to do with the way it interacts with the Mitsubishi accelerator lever. I swapped it for the original Mitsubishi one. Maybe leave it in place, but keep an eye on it.


The two injection pump plugs will plug into the existing wiring harness, but Hyundai have swapped some of the wire positions around, which is insane. You'll have to trace which wires go to which pins on your old IP and move the Hyundai pins to match. Yank out the coloured plastic tag in the middle of the plugs, gently lever the black plastic locking tag away from the pin you want to move, and then swap the pins to the correct positions. Reinstall the coloured plastic tag.

The tachometer sender black wire needs to be connected to the earth wire (the thick wire with the ring terminal). I pulled the sleeving back and made the join where it will never be seen.


Sump and oil pickup need to be swapped over. Caution: the D4BF is supplied full of oil. Drain it first. Trust me on this one.

The Mitsubishi oil pickup is bolted to a special bolt on one of the bearing caps- you'll need to swap that bolt over to the new engine. Install the new bolt to the correct torque (58 Foot Pound/78NM), then slightly loosen and re-torque the other bolt on that bearing cap (the two bolts must be at the same torque).
BEFORE INSTALLING THE DELICA SUMP swap the dipstick tubes over. The block is drilled for both dipstick positions, knock the blanking plug out of the rear hole and reinstall it in the front with a little grey silicone, then install your old dipstick tube in the rear hole. You must re-use your original dipstick and tube. The block's two dipstick tube holes are different heights, and the tubes are different lengths. Mixing and matching tubes or dipsticks will result in an incorrect oil level.

Check your old sump for internal damage. On mine, the windage tray had fatigued and split at one end where it's spot welded to the sump. I just welded it up.

Thoroughly clean and degrease the sump and block mating faces. Use grey silicone to install and seal the sump. Follow the workshop manual and instructions on the silicone (usually you lightly tighten all the bolts very evenly, let the silicone set for an hour or two, and then torque the bolts.)

L300 oil pickup bolted to #3 bearing cap bolt.

D4BF oil pickup.

You'll also need to swap the alternator oil drain hose.

The L300 steel air inlet pipe needed a tiny piece filed off one of the mounting tags to clear a new protrusion on the Hyundai inlet manifold. (Unmodified inlet pipe pictured):


Swapping the flywheel for the flexplate was straightforward, they even use the same length bolts. Observe the workshop manual's recommended torque (130-140Nm or 96-103lb.ft) and tighten the bolts in stages, in a diagonal pattern (like tightening wheel nuts).

Alternator
The Hyundai alternator has a Type 5 socket, your old alternator is a Type 1.
.

I found a matching plug on a wrecked car and fit it to my wiring.

The red or red/white wire is S ("Sense")
The other wire (blue, green, or white/blue) is L ("Lamp")



Swap the alternator tensioners over, the Hyundai one is primitive and difficult to use. Yes, it's even more difficult than the L300 tensioner, if you can believe that!

Oil pressure light switch also has a different plug- I just swapped the switches.

Oil cooler lines are attached with banjo bolts, so there's no issues there (unlike on a Pajero engine). When fitting a new engine it's a good idea to also fit a new oil cooler, as the old one might be full of crud. I simply washed mine out with gasoline- fill oil cooler, shake, drain, repeat until clean, then dried it out with compressed air. The oil filter on our engines is after the oil cooler, so any crap that comes from the cooler should be caught by the filter.

Swap over the AC pump bracket, tensioner, and pulley. You'll need to swap the tensioner retaining bolts from your old engine onto the new one.

 

[Growlerbearnz]

SWAPPING OVER/ADJUSTING THE INJECTION PUMP LINKAGES:

Most of the credit for this part goes to @ccmickelson who's been a guinea pig, following my original instructions and helping refine them, who's taken almost all the photos, and also corrected the occasional... ok, frequent errors and omissions.

The Hyundai engine is supplied already tuned and set up. To use the engine with our Mitsubishi accelerator and transmission cables, we're going to have to move the Mitsubishi IP linkages onto the Hyundai pump, and if we're not careful we can mess up Hyundai's tuning. It's not the end of the world if that happens, it's just a bit more of a hassle.

on the Hyundai IP:

Lift away the TPS, boot (if fitted), and plastic link nubbin to expose the 10mm nut holding the Hyundai accelerator link to the IP shaft:

What you find under the TPS

Removing the plastic link thingy

With the Hyundai accelerator lever at rest against the Hyundai idle screw, TAKE A PHOTO of the IP from above, one which clearly shows the orientation of the metal shaft in the middle of the spring (black shaft with pink marker notch on top). When you're done swapping the accelerator lever over, you want the splined shaft to end up in the same orientation to maintain the factory idle setting.


Shaft orientation with accelerator lever at idle. Also shows where the return springs are hooked to the drum and lever.

Now we're ready to install the Mitsubishi accelerator lever onto the new IP.

Note where the upper and lower return springs are hooked to the IP body. (photo of completed swap for reference- ignore the Mitsubishi linkages that have suddenly appeared)

Unhook both return springs from the drum and accelerator lever to release the tension. (You might need to make up a hook tool to get the lower spring off. You'll almost certainly need such a tool to reinstall the spring later.)

Undo the 10mm nut and remove the top spring, drum, and plastic spacer thingy.

About to lift the Hyundai accelerator lever off the splined shaft.

Lift the lever directly upwards off the splines without letting the splined shaft rotate.
If it rotates, refer to the photo we took earlier and put it back.

From now on take great care not to rotate the splined shaft.

Install the Mitsubishi idle speed screw and bracket onto the Hyundai IP.

Adjust the screw until it's about halfway along its travel- about 8mm of screw threads protruding.

Remove the Hyundai idle speed screw- it's the horizontal screw on the engine side of the injection pump near the top, the Hyundai accelerator lever would have been touching it when it's at idle. We're using the Mitsubishi idle screw (which is far more conveniently situated at the front) so we don't need the Hyundai one.

Removing the D4BF idle screw I had to reposition this fuel hose connection...

...continue to next post...

 

[Growlerbearnz]

Take your Mitsubishi accelerator lever from your old IP, and install it onto the splined shaft so it's touching the Mitsubishi idle screw. Again, do this without allowing the splined shaft to rotate. You might find that the splines don't allow it to be installed exactly touching the idle speed screw, in that case wind the screw out (left/shorter) until you can install the accelerator lever without allowing the splined shaft to rotate.

Reinstall the upper return spring and drum, and the 10mm nut. Be sure the return spring's lower hook is in place around the full speed screw- it's a pain to reposition once the 10mm nut is on.
@ccmickelson says: I also had to slightly modify the new drum to fit onto the Mitsu lever properly. The space between the center hole in the drum and the inside of the tab was not large enough to allow me to install the drum properly onto the Mitsu lever, so I used a dremel to make a slightly larger cut on both sides of the tab so it would bend out just a hair more.

Then replace the springs...

Then replace the rest of the parts...

And TPS...

Automatic vans: Install the Mitsubishi kickdown levers.They will have been dangling from the Mitsubishi accelerator lever all this time, so you're not really going to forget them.

Install the AC cutout switch (plunger type switch which is activated at full throttle). This will require installing the Mitsubishi wiring connector holding bracket. If yours is broken or you just don't have one, don't worry about it. It hardly makes a difference anyway.

Once the engine's installed, reconnect the accelerator and kickdown cables, ensuring both have the required amount of free play.
Double check that you have oil in the engine, pump the bleed pump on the fuel filter bracket until it becomes stiff, and then start the engine up!

It should idle at 750rpm, and engine speed should increase the moment the accelerator lever leaves the idle speed screw.
-If it's idling around 600rpm, and the accelerator lever can move 5mm from the idle speed screw before engine speed really starts to pick up, you might have the accelerator lever one spline off. Remove it, rotate it clockwise (as seen from above) one spline, and try again.

-If it idles too high, and winding the idle screw back won't bring it down to 750rpm, you're one spline out in the other direction. Remove the lever and reinstall it one spline anticlockwise.

Finish off the plumbing (see below) and you're done!

First Startup tips:
Charge your battery overnight so it's topped up.
Check oil and coolant levels.
Pump the primer (black knob) on the fuel filter bracket until it goes stiff (fills the IP with diesel).
Unplug the square plug on the IP (prevents the engine starting while you're bleeding the injectors)
Loosen the fuel line nuts at the injectors, wrap with rags to catch the mess, and crank until you see diesel coming out. Tighten the nuts.
Plug the IP square connector back in, let the glow plugs do their thing, and it should start up.
Make sure the oil pressure warning light goes out when the engine starts!
Keep an eye open for oil leaks, especially around the oil cooler.

Your new engine will feel a little sluggish for the first 1000km as it breaks in, and will continue to get smoother and more powerful over the next 9000km. I recommend an oil and filter change at 100km, 500km, 1000km, 5000km, and thereafter an oil change every 5000km, with a filter change every second oil change (10,000km).

Don't baby the engine when breaking it in: it's made to modern standards so it's mostly broken in at the factory, but also diesel is an excellent lubricant. If you treat the engine gently at first it can glaze the cylinder walls, preventing the piston rings from ever fully mating with the cylinders. Just drive it like any other vehicle and enjoy the extra power.

For bonus warranty-voiding credit, tune the engine for more power. You're probably going to be happy with the power it has simply because it's a new engine, but it can make a heap more...

 

[Growlerbearnz]

Vacuum and boost lines:

If you've removed the Exhaust Gas Recirculation you can also remove the metal pipes on top of the rocker cover and plumb everything up tidily like this: (Boost gauge is optional but strongly recommended).




The Purchasing a new Engine thread is worth a read, as is D4BF swap thread by @ccmickelson

(Yes, this post is a placeholder in case we need to add more to this thread)

 

[Kellyn]

Amazing write up. Simply amazing. Thank you Growler.

 

[Growlerbearnz]

UPDATE: Watch out for the right hand side engine mount. The D4BF block has an extra strengthening rib that might touch the engine mount, transmitting engine vibration directly into the chassis. Simply grind or cut a little off the engine mount to give it some extra clearance to the block:

This bit:


About 3mm clearance, which closes up when the engine's making torque. See the paint worn off the engine block on that corner?



Choppy-choppy. I did this in situ with a swazall, but it's easier and safer to do it with the engine mount on the bench.

 

[Growlerbearnz]

Update: Some folks have found their starter motor is chewing up the ring gear after installing a D4BF. We're not sure why just yet, but one thing to check is the number of teeth on your starter motor gear: the D4BF ring gear requires a starter with 13 teeth, but some starters only have 12 teeth.



If you're using the D4BF flywheel, use a 13-tooth starter. If you're using your old flexplate then use your old starter, or check that the new starter has the same number of teeth as the old one.

 

[paul]

Figured I'd let anyone looking at this guide know that after a long COVID related hiatus we've resumed regular D4BF shipments, they will be purchasable from our website 4-6 months from this post.

DelicaForum.com is run by Good Karrma and DelicaPartsUSA.com, and if you're new to the forum you can see that we arranged the previous group buys and are a safe source for D4BFs.