w123 emissions filtering?
 

hi,
i'm a new owner of a 1985 300D

i've read through some of the links here on the trap oxidizer and oxidation catalyst.
http://www.peachparts.com/shopforum/diy-links-parts-category/229522-trap-oxidizer-links-thread.html

i imagine in 2015 it's still true that they can cause damage to the turbo.
do they actually create more emissions in exchange for a cleaner looking emissions?

and my main Q is, is there any emissions filter that can be put later in the exhaust that will actually clean emissions a bit?

thanks,

First off, I don't think they ever installed trapox on W123's. I'm sure someone will speak up to correct me if I'm wrong.

Second, beware the group grope on the subject of emissions systems. Quite a bit of what you will read on the subject is simply wrong. For example, the trapox on early W603's wasn't simply removed by Mercedes...it was moved further down into the exhaust system. The original sat on top of the motor. Because this was found to cause mechanical damage, the replacement was inline with the exhaust pipe, after the turbo. You can see what I'm talking about here:

MBexh

A trapox is a dead end catalyst, meaning that exhaust goes into a porous ceramic matrix that dead ends. Particulates, ie soot, get trapped in the matrix, but gasses can pass right through the porous ceramic to the exit. When the engine heats the trapox sufficiently, the soot is burned in a catalytic reaction, yielding CO2 and water vapor, which can pass through the substrate. It can be infinitely regenerated just by giving the engine a good hot run...the FSM suggests running it on a dyno at 3000RPM for five minutes in the shop. On the road, a good blast on the highway takes care of it...the origin of the "Italian tune up" concept.

As for "creating more pollution", no. The EGR system is a tradeoff between NOx creation and soot creation. Trapox reduces soot and allows a little bit of additional EGR, all of which goes to reducing pollutant output.

Not that any of this applies to your car.

That is not correct. If the OP's 1985 300D W123 was a California market car, it did indeed originally come with a trap ox, with instructions that it be changed at the dealer every 35,000 miles. It also would have the 7xx.4 transmission.

At some point (1991?) MB sent a letter to all such owners asking them to come in and have the trap ox replaced by a trap cat, which would not need periodic changing, and would not break up possibly damaging the turbo, etc. On the W123, it is often difficult to tell by looking alone if this work was completed because the trap cat looks almost exactly like the trap ox. On the later I-6 diesels, the before and after difference was visually noticeably as mentioned by Mxfrank--not so on the W123. You can give the dealer the car's VIN and they should be able to tell if the campaign was completed on the car.

The trap cat, while not likely to break apart and damage the engine, can clog over time, and some people replace it with a straight pipe. I believe ROLLGUY sells a "kit" to do this; other sellers do as well. Here an old post by forum member Jeremy5848 detailing his installation of such a straight pipe in his old '85 300D (which was a beautiful car-still wish I had bought it!): http://www.peachparts.com/shopforum/diesel-discussion/221481-1985-300d-t-ca-trap-cat-removal-diy.html

-Chris

For those that believe that the trap cats do not come apart, you might be interested in reading this thread -

http://www.peachparts.com/shopforum/diesel-discussion/322498-you-might-want-check-your-trap-cats.html

These are the fragments that were lodged in the turbo when I tore mine apart!!

http://www.peachparts.com/shopforum/...cats-trap3.jpg

Strongly recommend getting rid of all the excess crap off the engine...it only hurts performance and efficiency and can cost money in the long run.

Wow, that's interesting and good to know. Somehow I missed your thread the first time around. I wonder what the difference between a trap ox and a trap cat actually is/was? I ask because the photo posted looks exactly like the inside of a trap ox I was shown at my indy years ago. Now I can put this in my "something else to worry about" file....

Yep, the 85 Kali 300S/SD came with a Trap oxidizer.
They were to be changed like Volvo Diesel said, every 35K miles.

When we bought the 85 300D I didn`t know about the Trap or much other about these 123`s.
An old German car sales man told me to buy an 83 and stay away from the 85 and 84. Do I listen? NOOOO. :rolleyes:

The 85 seemed sort of doggy and took it into a Indy, they ran the Vin# with MB, and it had been on over 50K miles.
So off to the dealer and they replaced it no charge with the newer TrapCat.

We went up to Vail Co. and that is around 9 - 10K ft elevation. This 85 was really a dog at that elevation.
A 240D auto would have had better get up and go.

Was using another Indy, and he said to change the engine to like an 83 is.
So off to the various wrecking yards to find all these parts.
Had him install them, and then the next summer we were back to Vail.
I thought I was in a Corvette. The difference with that damn thing off was like night and day.

The EGR dumps exhaust into the intake manifold along with the oil vapors from the VC and goops it up with this tar like crap.

I have never come across a 617 engine that the hole in the manifold where
the EGR dumps into was not totally plugged up.
Probably 99% of them do not work.


Charlie


sent from my pos computer

Probably the best thing to clean up a the diesel engine is to tune it up.

Valve Adjustment
Timing
Injector Service

My 84 300SD has near 350,000 miles and you would be hard pressed to get it to smoke. Because these engines will run and run, rarely is the proper maintenance done. Frankly, most of the added on systems have a next-to-nothing effect on cleaning up emissions and are only there to provide job security to government entities.

If this car was a really good deal and you had the mechanical knowledge to fix/replace things.....I would buy it and simply put on a intake/exhaust manifold from an earlier turbo engine.....

This one, probably also has the what 60$ air filter too....That would be enough to get me to switch out manifolds :P

If he goes that route, in addition to the manifolds, he should get the turbo, down pipe, turbo feed line, drain line, air cleaner and probably some other bits I'm forgetting. There's also another minor detail and that is the '85 pan doesn't have the oil separator port, so a catch can is probably in order.

It's obviously easier to just keep the '85 setup and get Rollguy's EGR block off plate and test pipe. Plus it's easier to add an EGT port with that setup too. He'll save money on gaskets too.

Well then......I would stay away from the 85 year......

But he's already got one...

Hahahaha Stay away from the car you already have.

I'd think the Cali air filter set up is desirable due to the lack of vibration and noise.

thanks for the responses. i doubt it's a cali model, but i'll try to call the dealer tmrw just in case they do have something on record.

whether it is or isn't, or had a trap ox or ox cat previously or currently, i was curious if there were options to filter for cleaner emissions.

Oh, to retrofit? Sure, you could have a cleanable DPF put in and have it cleaned every 2 years. You could ensure that your EGR valve is clean and operational in the situations it should be, and adjust your ALDA is set correctly so that you don't have black smoke as you accelerate. Other than that, burn a high cetane fuel.

i just read through this topic
http://www.peachparts.com/shopforum/diesel-discussion/372156-so-non-catalyst-diesels-really-dirty-then.html
the best i could, trying to sort through all the off topic chat.

between there and my other searchings, it seems all pretty complicated, and no clear solution to try to reduce emissions that could be filtered.

it seems DPFs are pretty complicated, and very pricey? aging the turbocharger doesn't sound great.

urea filters in bluetec sound good, but to retrofit that into a 1980s diesel... also sounds complicated.

it seems like diesel hpr has the lowest emissions, but only available in california. i haven't read through much about it... i imagine there is something unclean about it.

i know it's all unclean, i was just thinking, oh, filters exist, i wonder if we can do that on 80s diesels.