MB Diesel engines
 

Why are MB diesel engines so darn reliable?

1. Because many MB diesel owners are meticulous about the maintanance of their vehicle?

2. Because the German engineering at the time (up to 1985 as some say) was second to none?

3. Because diesel engines are just more reliable than gas engines?

4. Or all of the above?


Which leads me to ask...Are/were the American diesel engines any good? How about VW diesel engines?


Just a question that has been occupying my days as of late.

I received my first MB, 1981 300d, about six/seven years ago. When my Mom first bought that car "used", I said to her, "what are you crazy! Your'e going to dump a bunch of money into it. And it's expensive to maintain" It had about 150,00 at the time and I was unfamiliar with MBs. Well, she later gave me the car with 200,000 miles, I bought it because money was short and the price was right, not because I had a love or understanding of MBs. At the time, I was skeptical, I just needed a "station car".

Well I'm on my second one now. I lost the last one because of a guy hitting me in the right pass tire, bending the control arm and sway bar (not woth fixing). The car had 250,000 and probably would have gone another 250,000 if not for the accident.

Of course owning one, I had to get another and ended up with an '83 with 124,000 miles, clean as a whistle.

Anyway, getting a little carried away with the history, but you can't beat these cars. As long as it is maintained, it will be your best friend. Besides of course your dog, wife and kids...not necessarily in that order. it's a shame they do not make them like this anymore!

Any thoughts on the reliability of the classic diesels.

One major difference in American passenger car Diesels is that they were converted from some base gasoline engine. If this were a smart thing to do, MB would have figured it out in 70 years. OTOH, VW IDI Diesels are based on gasoline engines but are much more durable and reliable than the GM 350 Diesel or the 4-banger in the Chevette. Not sure about the TDIs.

Sixto
95 S420
87 300SDL

I've been told the Isuzu made engine in the Chevette was a good one, just rare.

The VW's are every bit as reliable as the Mercedes parts, and simpler to be honest. And weaker, which is important too.
For a converted gas engine, there amazing. The turbo models don't last as well, but there not at all bad if well cared for. The non-turbo's are rock solid as long as they timing belt is changed and there not overheated. Stupid aluminum head.
The car/trucks they were placed in are of varying quality, but all remarkibly simple.

Re: MB Diesel engines
 

To answer the first question, 4. All of the above.

To answer the second question, it depends on the engine. As sixto pointed out, GM's passenger car diesels were converted gasoline blocks, and their resounding failure almost singlehandedly made many Americans hate diesels. :( If that fiasco hadn't happened, I think we'd see a much higher percentage of diesels on the road today...

GM's pickup diesels weren't converted gas engines (in fact, although built specifically for GM, they're Detroits), but (some people will disagree with me on this) they still left a lot to be desired. Some people have said that they're reliable, but I have seen little proof to this, and have seen evidence to the contrary (blown head gaskets, thrown rods, etc). In addition, they're not exactly hot rods (a 6.2l has about the same power ratings as an OM617, except that it's double the size and trying to move a 6,000lb brick instead of a 4,000lb midsized sedan), and at least to me, they sound like they're congested or something.

Ford's diesels (built by International-Harvester)...well, their IDI engines (built up to '94) are basically reliable and have enough power to get the job done, but I wouldn't call them hot rods either (but not as anemic as the GM engines), and there are a few issues. Their later Powerstroke diesels are powerful, but I'm not a big fan of the electronics (a failed crank position sensor WILL leave you stranded with no way to get home unless you have a spare).

Dodge's diesel (built by Cummins) is simply amazing. They can get past 1 million miles if treated right, and even after being modified, can have a respectable lifespan.

As to Volkswagen...their newer engines may be different, but (before being bitten by the M-B bug), I chose my 300D over a diesel Jetta because I was worried about head warpage (also why I didn't get an OM603). For reasons besides the head issue, I'm really happy that I got the M-B, although there are times when the VW's fuel mileage is appealing...25mpg is still better than the 13mpg that I was getting out of the van that my 300D replaced. :)

Thanks for all of the responses. I learned alot today.

Let's not forget about the Detroit Diesel 2-Stroke engine that were produced in many configurations. Talk about power, reliability and simplicity from the 53 Series to the recent DDEC 92 Series that continues to power many things today.

I have to take issue with that claim of the old DDC two stroke diesels. Powerful, they were not. They had to be revved hard, all the time, to make any semblance of power. They also puked oil all over the ground worse than anything else out there built by any other engine manufacturer. DDC's do have a very distinctive sound to them, with the two stroke design, and high revving nature. The only real reason why you still see them used in some applications is due to their simplicity. They are cheap to keep running.

2250 rpm is revved hard? Naaaa, they just sound like you are spinning the guts out of them.

Sixto is right. I worked at Chrysler back in the early 80's on diesel engine development. Chrysler essentially just wanted to convert the 4-cyl 2.2 and slant 6 to diesel, projecting 25% of their vehicles would be diesel.

During design interations, Chrysler ended up modifying nearly EVERY component on these engines.

The end of gas shortages, and a drop in gas prices, plus the class action suit against Oldsmobile diesel engines put an end to any demand the American public may have had for American made parrenger car diesel engines.

Diesel engines should be designed from scratch.

Yes. In that class of diesels, that's revving them hard. LOTS of recirculating mass in those things. They only made useable power at the high end of their RPM range.

Spin is what they're made to do. Well, DDEs at least, that and fling oil all over your engine room and bilge.

As a side note, I've spoken to a few people and read online that there were ways to get the GM 350 diesels to be reliable. Head studs were part of the reciepe as I recall. I know they have a loyal following out there which enjoy the fact that you can buy them for next to nothing. I always wanted to play with one.
It was an oldsmobile 350 V8, and the block, crank and rods were reinforced, we used to use those parts to build very serious gas engines for drag cars. :)

IIRC, there are also loyal followings out there for the Chevy Vega, the Ford Pinto, the Yugo, and the Chevy full-size "pickups" ;)

*flame suit on*

Wow; you have a *flame suit on*
 

:DWow; you have a *flame suit on*!!!!!!!!!!!!!
:DI just use the icemaker and a large adult beverage as I LOL.

:DI wonder why people list the cars they owned, here is my current list, sorry that 45 are still missing.

(sold) (1) 1960 Rambler V8
(sold) (1) 1961 Cadillac Fleetwood V8
(sold) (1) 1961 Cadillac Deville V8
(sold) (1) 1966 Ford Ranchero V8
(sold) (1) 1966 F350 steak bed V8
(sold) (1) 1966 F250 steak bed V8
(sold) (1) 1966 F350 box bed straight 6
(sold) (1) 1966 F250 steak bed V8
(sold) (5) 1970 Ford Pinto straight 4
(sold) (3) 1970 AMC Gremlin straight 6
(sold) (2) 1971 Ford Pinto straight 4
(sold) (2) 1971 AMC Gremlin straight 6
(sold) (7) 1972 Ford Pinto straight 4
(sold) (3) 1972 AMC Gremlin straight 6
(sold) (1) 1972 Cadillac Coupe deVille V8
(sold) (1) 1973 Oldsmobile Delta 88 V8
(sold) (5) 1973 Ford Pinto straight 4
(sold) (2) 1973 Chevy Chevette straight 4
(sold) (1) 1973 Ford Torino V8
(sold) (5) 1973 AMC Gremlin straight 6
(sold) (3) 1974 Chevy Chevette straight 4
(sold) (4) 1974 Ford Pinto straight 4
(sold) (1) 1974 Ford Mustang V6
(sold) (1) 1974 Ford Mustang straight 6
(sold) (2) 1974 AMC Hornet straight 6
(sold) (2) 1974 AMC Gremlin "X" straight 6
(sold) (1) 1974 Cadillac Eldorado V8
(sold) (3) 1975 Ford Pinto straight 4
(sold) (1) 1975 Ford Mustang V6
(sold) (1) 1975 Ford Mustang straight 6
(sold) (2) 1975 AMC Gremlin straight 6
(sold) (2) 1975 AMC Hornet straight 6
(sold) (2) 1976 AMC Gremlin straight 6
(sold) (1) 1976 AMC Hornet straight 6
(sold) (1) 1977 Ford Mustang V6
(sold) (1) 1977 AMC Gremlin straight 6
(sold) (3) 1977 AMC Hornet straight 6
(sold) (1) 1979 Pontiac Monte Carlo V6
(sold) (1) 1980 Chevy Citation V6
(Own) (1) 1985 1985 300SD Diesel straight 5
(Own) (1) 1990 Dodge Shadow straight 4
(Own) (1) 1993 Dodge Shadow Sport V6
(Own) (1) 1995 Pontiac Grand Prix Sport V6
(Own) (1) 1945 Cadillac V8
Still have 45 vehicles missing from this list.
Should I count parts cars?

"NO", I am not; and have never been a car dealer.

LOL, I saw some gremlins and Pintos in there I believe, that's just hilarious.
Have a nice day
David