http://www.toyota-industries.com/environment/product/engine.html

"So that the diesel engines we develop will meet European exhaust emission regulations STEP III (Euro III), we have adopted the swirl control valve (SCV), which is a first among Toyota diesel engines, a diesel throttle, and the EGR gas electronic control with EGR cooler. Through these measures, reductions in NOx and particulate matters (PM) have been achieved."

Sixto
93 300SD 3.0

I believe the newer MB/Dodge Sprinter's have cooled EGR valves.

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1977 300d 70k--sold 08
1985 300TD 185k+
1984 307d 126k--sold 8/03
1985 409d 65k--sold 06
1984 300SD 315k--daughter's car
1979 300SD 122k--sold 2/11
1999 Fuso FG Expedition Camper
1993 GMC Sierra 6.5 TD 4x4
1982 Bluebird Wanderlodge CAT 3208--Sold 2/13

An EGR cooler reduces intake charge temps. This makes EGR more effective at controlling NOx. This allows automakers to use less EGR and meet the same emissions or use the same amount of EGR and meet more stringent emissions.
It also ups the power slightly (when EGR is used) because less heat energy is lost to the cooling system and more of it stays in the gas where the piston can extract work from it.

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green 85 300SD 200K miles "Das Schlepper Frog" With a OM603 TBO360 turbo ( To be intercooled someday )( Kalifornistani emissons )
white 79 300SD 200K'ish miles "Farfegnugen" (RIP - cracked crank)
desert storm primer 63 T-bird "The Undead" (long term hibernation)

http://ecomodder.com/forum/fe-graphs/sig692a.png

VW TDI's have EGR coolers too, and there's a recall on them for the '04 and '05 model years due to potential internal leaks. So far mine has been ok.

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2004 VW Jetta TDI (manual)

Past MB's: '96 E300D, '83 240D, '82 300D, '87 300D, '87 420SEL

Have you guys Heard of anyone upgrading the OM603 turbo engine with a EGR cooler?

Any ideas on doing so?

Tks,

Oldbeaver

Be sure that the cooler doesn't corrode and start feeding your engine coolant

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$60 OM617 Blank Exhaust Flanges
$110 OM606 Blank Exhaust Flanges
No merc at the moment

VWs TDIs have had cooled EGRs since the 1997 model year. Cooler gas = less NOx. Our Passat has 2 EGR circuits, and IIRC 2 coolers

IMHO NOx isn't that big of an issue. Adding a cooled EGR to a 603 probably make a huge difference. The major pollutant on these engines is probably HC and particulate matter.

-J

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1991 350SDL. 230,000 miles (new motor @ 150,000). Blown head gasket

Tesla Model 3. 205,000 miles. Been to 48 states!
Past: A fleet of VW TDIs.... including a V10,a Dieselgate Passat, and 2 ECOdiesels.
2014 Cadillac ELR
2013 Fiat 500E.

Your understanding of Diesel emissions is incomplete.

Diesels actually make little HC (or CO) and the PM is only a concern because PM carries non-particulate bound organics which are carcinogens. Lower PM and you lower the organics. The part you see is just carbon.

You are right that cooler gas = less NoX. But NoX IS a big deal. It's the catalyst in photochemical smog and is REALLY toxic. Diesels make a ton of it. NoX is a formed by temperature, pressure, and time. Diesels have high combustion chamber temps, LOTS of pressure, and relatively longer times due to the relatively low engine RPMs compared to Otto-cycle engines. Much of the development in the Diesel engine field has been aimed at reducing NoX for those reasons.

Just FYI - I'm retired from the EPA where I was a tech working on Diesel aftertreatment development as well as EGR applications.

Dan

Dan,

Cool! I had read a number of studies suggesting that NOx isn't as bad as was originally thought.

I meant to say that adding a cooler to a 603 won't make a huge difference

-J

__________________
1991 350SDL. 230,000 miles (new motor @ 150,000). Blown head gasket

Tesla Model 3. 205,000 miles. Been to 48 states!
Past: A fleet of VW TDIs.... including a V10,a Dieselgate Passat, and 2 ECOdiesels.
2014 Cadillac ELR
2013 Fiat 500E.

I wouldn't add any emissions equipment unless I had a regulatory agency making me. Some folks here disable their EGR because running without is better for the engine. Whether this is legal varies depending on where you are.

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Whoever said there's nothing more expensive than a cheap Mercedes never had a cheap Jaguar.

83 300D Turbo with manual conversion, early W126 vented front rotors and H4 headlights 400,xxx miles
08 Suzuki GSX-R600 M4 Slip-on 22,xxx miles
88 Jaguar XJS V12 94,xxx miles. Work in progress.

Again speaking generally (not necessarily about Mercedes) most modern engines are calibrated for EGR and disabling it does NOT help the engine. In fact, it can cost you fuel economy, again because the engine is calibrated for it. To properly remove EGR involves changing the cam, reprogramming the computer (at least in Otto-cycle engines), and other smaller mods (thermostat temp change, etc.). Sometimes even the compression ratio is tailored for EGR.

On our older Diesels I suspect that removing the EGR probably helps keep the intake tract cleaner and lowers intake temp - always a good thing. I do not have EGR on my 617 in the S-10 but it is race-only and will never see a mile of road duty. As stated, local and state regulation will effect the legality of that mod.

An interesting tidbit - on Otto-cycle engines installing a high-overlap cam (common in performance applications) ADDS EGR in a passive manner. In areas that accept an exhaust test as proof that an engine is "clean" it's one of the things that is done to lower NoX - and it works. Coupled with an oxydizing cat to clean up HC and CO (like the generic CATCO cats available from Summit or Jegs) and you can pass almost any car assuming that the engine is in good condition.

Dan

I agree. My 2.5L gasser wasn't happy when the EGR pipe cracked.
On the other hand, the Heep doesn't have an EGR and passes emissions just fine

__________________
$60 OM617 Blank Exhaust Flanges
$110 OM606 Blank Exhaust Flanges
No merc at the moment