That's your EGR. It takes a small portion of the exhaust gas and runs it back thru the intake. This lowers combustion chamber temps a bit and therefore lowers NoX emissions which tend to be high on Diesel engines. I have removed mine on Mutt the Race Truck but it only sees a few miles/year on the race track. You CAN remove it but it depends on your feelings on lowering emissions vs keeping an old car (or engine in your case) on the road.

Dan

How does putting hot exhaust into the intake help keep the engine cooler?

Is there anyway to make the turbo louder? I loved how on my dad's old power stroke you could here the turbo wine right above idle and I'd like my truck to sound similar if possible

I have a feeling it actually increases the temp, burning off bad stuff. Generally folks tend to remove them most of the time.

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[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.

That makes more sense. I'll keep it

Exhaust gas is a ready source for inert gas to reduce oxides of nitrogen not a heat source. Some engine use an EGR cooler , other long runs of piping.

NOx is produced when nitrogen and oxygen are heated to high temperatures causing them to fuse.

On a gas engine, EGR can actually increase efficiency at light throttle by increasing dynamic compression ratio. At light throttle / high manifold vacuum, there isn't much air to compress so dynamic compression ratio drops. If you pump in a gas that does not burn or oxidize, it fills extra space increasing dynamic compression ratio.

On a diesel I'm not sure there is much to gain other than reduced NOx .


You are not anywhere near that stage yet, there is still much to be done just to get the truck running.

If you run a straight pipe you'll hear plenty of whine.

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[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.

Oh ok thanks for the explanation. I know worrying about how it sounds is pointless but I'm running short on funds so to keep this project going, and keep me from getting bored, I want to do all the little things that'll make it cooler but don't cost much.
I got the bolt pattern of the Ranger's bell housing mesured so I'll draw up the adapter as soon as I get back from the roofing job I'm on. I'll try ad see if a shop teacher a friend and I had would be willing to cut the adapter out of wood on his CNC router to check it fits. I'd ask my friend do it after work but they don't like running wood because it makes the coolant gross.
When I compare the weights of the Mercedes and Ranger flywheels do I need to take into account how much the full torque converter weighs? I'm assuming so. If that's the case it looks like I'll luck out and be able to use an adapter to join both flywheels to the engine.

Rather than make the adapter and flywheel from scratch, buy a setup that works as you will be much farther ahead in time and $. It's comparatively easy to make the plate between the engine and trans but it is more difficult to get the flywheel, clutch and starter correct.

When making the adapter plate, you need to work from the crankshaft centerline on the engine and trans. Things must be aligned on the 0.005" or less of an inch range so a tape measure won't work here.

It doesn't make the engine cooler, it lowers combustion chamber temps. NoX (the catalyst in photochemical smog) is made as a result of temperature and time. Diesels have high combustion chamber temps and run at relatively slow speed meaning that there's more time available for the NoX to form. So Diesels are bad about making NoX but are pretty low in unburned HC and CO emissions. Mercedes added EGR to lower NoX emissions early on, I suspect to meet some international standards as here in the US it was no yet required.

For a better explanation of the relationship between EGR and the chemistry inside the combustion chamber you'll need to look up Diesel combustion chamber chemistry, probably on Google. It's a fascinating study! When I was doing this for a living I had a bevy of engineers and chemists I could ask and I have to admit that I haven't retained this info (I've been retired for 12 years).

Dan

My swap is straight piped, and you can hear the turbo plenty well enough once it spools. Don't expect just-off-idle turbo noise like a PSD though, stock 617's just don't spool that soon.

https://www.youtube.com/watch?v=eggByFXpVNE

You can hear it a bit in this video.

Also, my swap used a redrilled Toyota flywheel, I have no issues. I would expect your Ranger flywheel to work just fine, weight wise. Be aware that you'll have to have it balance matched to your existing flywheel.

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617 swapped Toyota Pickup, 22-24 MPG, 50k miles on swap

...which means you need to make sure you've got witness marks to get your new one matched properly to the engine.

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Current Stable

• 380SL (diesel)
• Corvette C5
• Manx
• Baja Bug
• F350 Powerstroke
• Auburn Boattail Speedster replica

Sadly there are no adapters that'll do the job so I've got to make it. Machining and metal costs will be low though so it won't be to bad. Oh and both flywheels have the same pitch teath on the ring gear which is great.
The bell housing was measured on a CMM, I trust those measurements way more then I do the Mercedes bolt pattern I found online.

That sounds awesome! Not as much turbo as I'd like but sounds good anyway.
That's a relief you used the Tacoma flywheel! I got all worried that wouldn't work because I saw somewhere the Mercedes flywheel is 38 lbs and when I weighed the one off the Ranger it was 18~. So the weight of the torque converter doesn't matter then? That things pretty heavy.
That's really cool!

Arg! I new I forgot something! I hope getting the Ranger's flywheel balanced should get it close enough

Few questions, for the glow plugs I can just wire them through a fuse and switch to the battery right?? When the glow plugs were heating( when the engine was in the car) it'd make a wining sound, that's just to let you know its doing something right? I don't need any of the electronics from the car right? What about the feul pump? I read one thread where a guy did this swap with his jeep and didn't use the in tank fuel pump. Mine decided to stop working so I could take the one out of the Mercedes if I have to. Also, how is this engine shut off? I ask all this because I have a friend who wants to buy my car and I want to make sure I've got everything I need.
I got a big piece of plastic so when I get back I can cut a test adapter out of it

For the glow plugs use a Ford starter solenoid. For the shutdown, use a switchover valve. Your fuel pump is on the engine so you don't need the one in the tank - in fact you shouldn't use it.

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Current Stable

• 380SL (diesel)
• Corvette C5
• Manx
• Baja Bug
• F350 Powerstroke
• Auburn Boattail Speedster replica

Glow plugs draw a TON of amps so you can't run body power directly to them. You'll need battery power and AT LEAST a 12 gage (I think I used 10 gage) wire thru a Ford-style starter relay. DO NOT get the starter one, get the ones used for snow plow actuators - they are made for continuous duty and will hold up to the glow plugs. I got mine at Car Quest and they knew exactly what to hand me. Not too expensive. Use a TEMPORARY switch (like a starter button) inside the truck to activate the solenoid. That circuit just takes body power, no high amps. No clue why the factory actuator stuff was whining - maybe it was feeling abused?

I don't have an in-tank pump. Remember, the injection pump is fitted with a lift pump which is made to pull fuel into the injection pump. Of course, I have a front-mounted fuel tank and a VERY short fuel line but I don't think you'll need an in-tank pump. Remove the in-tank pump or it will inhibit the flow to the fuel line running up front.

The engine shuts off by applying vacuum to the shut-off fitting on the rear of the injection pump. I needed the engine to shut off any time the power was removed (track rules) and it was a stinker to make that work. There are several ways to do the shut off system but I suggest you READ my build thread on here. All of the questions you asked were addressed in detail in that thread and I think it'll be well worth your time. If you need more details you can read my build thread on BangShift.com. which has even more info than the one on here.

Dan