617 EGR elimination - PeachParts Mercedes-Benz Forum

oldmako · #1 02-25-2016, 09:31 PM

Stupid question from an FNG -

I have seen quite a few MB diesels with the EGR removed and a blocker plate installed.
Or, I see a small cartridge air cleaner installed.

I am curious about the how and why. This forum seems to be the best place to get traction on issues like this, so I figured I'd give it a whirl. Last year I test drove a gorgeous Rod-Bender whose owner had performed the surgery. He was quite happy with it. I'll ask Mister Google as well and read up.

Many thanks in advance to all replies.

mannys9130 · #2 02-25-2016, 09:39 PM

It's simple. People think that soot in the intake manifold after 30 years is unacceptable. They are so taken aback that they need to clean buildup after 3 decades that they defeat emission devices to attempt to prevent it. Others cite recirculating exhaust into the engine as nonsense and undesired, but they only expose their lack of knowledge regarding NOx formation.

Deleting the EGR has no performance gains, and the intake only requires cleaning rarely. Us OM60x owners could clean it when we replace the glow plugs every 50-100k miles.

In your reading, be sure to look at the legal consequences of tampering with federal emissions control devices.

mach4 · #3 02-25-2016, 10:11 PM

First of all the "how to" is extremely simple - For Sale: EGR Delete/Block-off Plate Kit...just get one of these. If you've ever had the pleasure of cleaning out an EGR infested intake manifold you'll understand the why...as they say, "intuitively obvious to the most casual observer". Almost all EGR systems are clogged so replacing the "clog" with a "kit" is a net break-even from the perspective of emissions.

One of the more interesting aspects of active forums is the emergence of "single issue" posters.

Some people like to raise the issue of "legality". In a world where there are so many laws, it's physically impossible to not break many, often without even knowing, EGRs fall so far down on the list as to be unmeasurable. At a time when our leaders flaunt the laws on really serious issues like following the constitution, maintaining security, bribery, sanctuary cities, illegal aliens, and on and on and on, I don't have a problem in following the example being set on insignificant and irrelevant technical violations.

Bottom line - if you're an EGR fan, great, go for it...and if you're not, fine too. Make your choices and live with the outcome. And of course respect dissenting views.

BillGrissom · #4 02-25-2016, 11:10 PM

The air cleaner change is usually mostly because the factory air cleaner mounted to the intake manifold suffers from bracket failure. Some may have done so for performance reasons. 1985 CA engines had a frame-mounted air cleaner. I installed one on my 1984 engine (see "No more whole lotta shaking ..." post).

Whatever redesign, you need to route the PCV blow-by gases to the inlet of the turbopump and need to manage the entrained oil drops. The 1985 CA design just ran it straight in, oil and all. Some people use an aftermarket oil catcher (ebay). I ran a tee off the PCV tube to the oil drainback tube in my 1984 engine, and similarly in my 1985 CA car since it now has an earlier engine. Note that 1985 CA engines don't have that drain tube nor was the boss for it machined in the upper oil pan.