Lower Splash Guard E420
 

My lower engine splash guard on my E420 is just about shot and I was thinking about permanently removing it. Has anyone experienced any problems running without the guard? I know some have mentioned that it will enhance the cooling, but I was wondering if there are any major down sides to this, like the alternator getting wet when it rains. I was also wondering if it was designed to enhance air flow and cooling, like some of the lower cowlings on other vehicles. Thanks.

That's the first thing I do with a car. It seems cruel to leave it on the car. It raises the engine temp, masks fluid leaks, thwarts oil changes, etc. 90+ percent of the cars on the road do fine without a belly pan.

It is there to channel airflow and protect the Belt from road debries.
It serves a function.

But Arthur, that airflow is so limited compared to taking it off entirely. I've done this several times - the cars consistently run 10 degrees cooler. I've even done on/off, on/off to test the temp. I don't think MB ever said it was there to cool the engine, but to manage the air temps - i.e hotter, for emissions. Add to that the nuissance of it, and the fact that it covers up fluid leaks, it's nuts on an older used car. Volvo used to do it, then just dropped it. I'm still suspicious that it's a ploy to keep customers away from changing their own oil.

<I don't think MB ever said it was there to cool the engine,>

Yes they do.
Factory Service manual.
But the main reason is to keep water off the belt to prevent slippage from wet roads. That is why the AC has a speed sensor on the compressor.

I almost forgot, MB dropped it too - on the 140 bodies, around 1996 I think. I had a VW service rep tell me that a factory rep admitted to him that while it served some purpose it's principal purpose was increasing service revenue. I'm not suggesting it has no purpose, it just has so many negatives on an older car, and it can't be really necessary or MB wouldn't have dropped it on the 140 body, and perhaps other models, not sure.

They are a pain in the ass....the mounting screw anchores always break...
I have cut a 4" access hole in a few with a drier vent saw so you don't have to pull it for Oil change...

But there is a cowel effect, probably more so on the 104. Belt protection is the main reason why I leave them.

No doubt a shop can't throw away parts like an owner can. I get great pleasure from throwing away what I consider to be superfluous parts - to make it easier next time.

What one considers a useless part has a lot to do with how much one knows about the logical reason and performance behind the part.
See guys dump cowellings all the time without any regards to the designs purpose..and there IS a purpose.

This is good information coming from both sides of the argument. It will be a difficult decision whether or not to buy a replacement. Thanks again, guys.

I'm sure I've thrown away hundreds of parts over the years, and with absolute impunity - never a single problem. Much of what I've thrown away MB doesn't even bother to put on the cars anymore. I think the 90s were the age of excess - lots of over-engineered parts and systems. In the end I think it's largely a personality issue. If your a minimalist you like keeping it simple. These old sedans are just going to the salvage yard anyway.

Yeah, I remember talking to some of the Engineers when the 124 was introduced, they were pretty proud of the "revenue-generating panel". That is a complete fabrication/BS by the way.

When the 124 was designed, the encapsulation panels were there for a reason. They keep the engine clean, provide proper airflow, allow the engine to run proper temperatures (if the engine is running hot, there's a problem), reduce engine noise, and reduce aero drag & lift.

It can be removed, you can run without it. I don't, I just don't like the filthy engine. If the engine leaks it needs repair anyway, but that's another story.

If you remove the engine panel, you will also want to remove the transmission panel as the air will eventually catch the transmission panel and pull it down, at least one forum member had this happen on a 124.

But you're missing the point - the question is not whether it had a purpose when the car was new but whether it can be removed on a 15 year old car. Obviously it can be. Way over 99 percent of the cars on the road over the last century have done fine without a belly pan. BTW, what do suppose changed on the 140 body - that for all those good reasons it had to have one, then suddenly it didn't need to have one. But the parallel doesn't work on the car in question. As to MB's altruism it's just a good thing they don't sell swamp land, because there'd be a lot of buyers.

On the 94 I just bought a few months ago, the sump guard/ belly pan is missing. And I want it.

(Marginally) Better fuel economy and also protects (somewhat) the oil sump/ pan. In exchange for 10F cooler temps? I'll take it. Thats what the fans are for. And the engine is designed to work at those "elevated" temps.

I would find out how expensive it is before I decide whether it is necessary.

I leave them on, but I'm not sure I would spend 80~90 bucks for one.