PeachParts Mercedes-Benz Forum - View Single Post

Jim B. · #2 05-12-2007, 07:22 AM

But, since you asked....

I'd try and find out EXACTLY what kind of engine was put in the car.
Was it a independent shop's mechanic or a Mercedes Benz dealer who put in the new engine?

Was it just a remanufactured motor, and if so, did it have the upgraded connecting rods in it or not?

The best scenario would be a brand new crate, long block motor installed by a Mercedes Benz dealer. It would have all the upgrades and be new.

But......even in that case, it's very possibly a losing gamble. While some members here report satisfaction with these cars, generally the odds are against you, even with a new engine in it. You wouldn't know whether the new engine was good until it started burning oil, but by then,,,,,it would be too late.

The engine is called the "rod bender" engine, and is widely believed to have a basic design flaw, the Mercedes diesel engine to avoid. It's been discussed at great length here, search "rod bender" here to start.

Then there is the 1992-1999 W140 body you are looking at. While hugely safe, quiet and comfortable, they are hugely complex and VERY expensive to fix when things go wrong, such as the AC evaporator, which requires removal of the front dash and seats just to access and fix, over 22 hours of labor required, it can be thousands of dollars, very quickly. It sounds like the car you are looking at, has this $3000+ issue right NOW. I wouldn't be surprised if that is the reason the owner is selling it, so he won't have to deal with it.
With some dealers charging $150 per hour, a 22 hour job is gonna cost a LOT!

The electronics, soft close doors, and other complexities make them a VERY expensive vehicle to keep up.

Frankly, a W140 diesel 3.5 car is, in sum, very likely to be VASTLY expensive should you get a poor example, and the odds of that are VERY high.

I wouldn't personally buy one, under ANY circumstances.
I'm not even going to ask what the price is. I woouldn't want one even for free!

Rather, I'd look for a beautifully kept 1981-85 300SD or an '86-'87 300SDL that was rust/accident free, with books and records, in a color I liked.
Those are proven to be good, dependable, long lasting vehicles.