Bill,

Yes this is true. Furthermore the car handles well enough that it's easier to produce that road kill. Okay pet lovers, I'm just kidding, I have pets too!

Have a great day,

Porting and polishing can be rather dangerous on a diesel engine if done incorrectly. The air that is being inducted into the cylinder is swirled by the shape of the ports and the area of the head that would be a combustion chamber on a gas engine. If that swirl pattern is disturbed you will lose combustion efficiency and lose power. That said, porting can be beneficial if done correctly in heavily fueled high boost engines. There is little gain in overall power, the gain is seen in lower EGT as the gasses are able to get out easier and faster. Porting and polishing is becoming more and more popular for the Cummins B5.9 performance enthusiasts. With the modest fueling of the MB engines it would be a waste of time IMO.

So then, when the time comes to rebuild our engines the best thing to do is get a good stock rebuild...is that the advice? Although my 240000 mile 5 cyl. diesel seems a long way from needing a rebuild, I like the car enough to rebuild the engine rather than replace the car, when the sad day comes that the old tank needs a new lease on life. Even the relatively high cost of a rebuilt engine is still less than replacing the entire car - replace it with what??? By then, all of the other 240's and 300 W123's will also have mucho miles on them, too (as if they don't already). What else has the solid structure, good handling & braking, and comfort of a W123? Unless the car gets hit, I am sure that with my regimen of car care, the 123 will still be solid and roadworthy. A new or rebuilt engine would give me another couple hundred thousand miles of usefullness, I'd expect. I doubt that I will outlast this car.
Back to the question - is there any modification that can be made to enhance the effectiveness of a stock rebuild? Balancing the short-block? Fuel injection improvements?? What, then???

Interesting. MB diesels do not use the ports to get swirl -- the prechamber design does that. Combustion takes place mostly in the prechamber, not above the piston as in a direct injection diesel.

American diesel engine design is a little backward IMHO. Too many simple things (like variable injection timing, duh!!) improve horsepower too easily for the engineering to have been done well in the first place. Way too much black smoke, too -- watch the Volvo trucks for how little can be produced -- they are also MUCH quieter, and get vastly better fuel milage -- on the order of 8 mpg fully loaded.

The quick and easy way to get more power after a rebuild is to put oversized pistons in rather than standard. I think a 0.020" (in metric, of course) size is available, and will increase displacement significantly. Re-balance crank if you put in larger pistons!

Peter

__________________
1972 220D ?? miles
1988 300E 200,012
1987 300D Turbo killed 9/25/07, 275,000 miles
1985 Volvo 740 GLE Turobodiesel 218,000
1972 280 SE 4.5 165, 000 - It runs!

To: 1991 SEC;
Dear Fellow Mercedes afficionado;
This is a diesel discussion group. We are all enthusiastic about the robust nature of our cars. They last forever, are very inexpensive to run, and are eminently repairable by people of modest means. That is enough for me. I couldn't give a R--- A-- if a Kia or a Wartburg is faster. If I want to drive like a nut, I have other vehicles that serve that purpose very well. As for diesel odor; It stays behind me. A diesel in a good state of tune does not emit much diesel smell, and there are discussions in our archives on how to all but eliminate smoking, and how diesels really pollute less. I have had these arguments many times, but usually with Chevy smallblock-driving goons, and not the owner of another Benz - but all MB's are perhaps the very best cars on the entire planet. Yeah, I'd like to have a 560 SEC, but I do not have the mechanical ability to repair one, do not wish to be a slave to a shop, and cringe at the thought of paying for premium fuel in the gas-guzzler. Yes, a diesel demands a small level of inconvenience in that they are less willing to fire right up in very cold weather without as block heater and anti-gel. My other vehicles have their own idiocyncratic inconveniences, too - I think of these as "character". They are not Camry's.
As for "shaking"...well, I hardly notice my 17 year old 240,ooo mile 300D shaking at all. The car is still in outstanding condition despite having nearly a quarter million miles on it.
If I won a lottery I would definitely consider buying an MB 560 Brabus prepared supercar or some such dream, but I live in my own reality...I will almost certainly never be able to afford that type of car.
So, I remain an oddball-eccentric-nutcase-whatever diesel afficionado. I love my Turbodiesel, and will keep it in peak operating condition for as long as possible.
If you do not understand, I cannot explain. Otherwise no explanation is neccessary.
Best regards

Now you know.

I have owned a gas-engine MB before, however it was not a 1991 SEC, (It was a few years older, too) and it cost me big bucks to maintain, and it needed work quite frequently despite being in very good condition and well maintained by its former owner . My AlfaRomeo is more reliable than that car. Hell, my Plymouth was also more reliable than that car. There is simply no comparison between the diesel Benz and the gas Benz - the diesel is just so very mush more reliable and a joy to own that it is like they came from two different manufacturers.

Well, how does 0-60 in 10 sec, 30+ mpg at 80 mph, and lifetime of 400,000 miles plus grab you, along with the comfort and driveability of a Benz?

Ditto for the Volvo TD -- a little slower, but slightly better milage, the only work at 200,000 miles on the engine has been the turbo (fried by previous owner) and an IP overhaul (standard on the VE pumps, they don't last).

stately, slightly sedate, drive literally forever, that is what I like about the diesel -- the 220D still runs at 30 years of age, doesn't appear to have been apart, still has one old style injector seal. Do that with a gas engine!

Peter

__________________
1972 220D ?? miles
1988 300E 200,012
1987 300D Turbo killed 9/25/07, 275,000 miles
1985 Volvo 740 GLE Turobodiesel 218,000
1972 280 SE 4.5 165, 000 - It runs!

I am very impressed. You must be rich or something.

Hi TXBill: Do we have an "Ignore" feature with this discussion group?
I am allergic to Ignorance.

1991 560 SEC, diesels do not have to be slow. In many cases they are in factory trim, but as mentioned previously they last forever and deliver economy that is unmatched in the gasoline world. For example, there is a Dodge 2500 extended cab 4x4 Cummins turbo diesel truck with 35" tires and a truck style OEM 5 speed transmission in Indiana that will run the 1/4 mile in less than 13.5 seconds. Yes you read that right, a 7000 pound street legal truck that will run low 13's all day. There are some faster, but this is just an example. If I remember right the world record for a diesel powered vehicle is under 10 seconds in the 1/4 mile, not slow by any means. Diesel engines have been capable of over 100 horsepower per liter of displacement for a long time. Drive a new TDI, they are a world better. Drive a new TDI with a CPC type pump controller on it, it will blow your mind. Gassers beware!!! There are some seriously powerful and quick diesels out there. If you are not into power and quick you could just laugh all the way to 400K miles too, while your gasser buddy goes through several engines.

BTW, this is not a flame, all in fun and to point out a segment of the performance arena that you may not be aware of.

EDIT: Forgot to mention that I am not fully aware of exactly how the IDI type of diesels work, thank you Peter. Peter, just so you are aware, DI type engines are in fact capable of variable injection timing as well, either mechanically or as of late electronically.

Man, I wish that I, too, was successful, wealthy and intelligent. Oh, woe is me!

I'm totally confused! Why is someone who "doesn't see the attraction to diesels" spending so much time in the Diesel Discussion portion of this forum?

Have a great day,

If you like quiet, you can buy an electric car and they get good gas mileage.

Some people don't like quite, so they put those noisey mufflers on their four banger Hondas and Acuras that sound like junk.

The new diesels are very quiet and get mileage that exceeds that of gas-electric cars.

Is gas mileage an issue? To those SUV drivers, I don't think so. To others who are concerned, it is.

If power is an issue, then why would someone drive a 3 banger Geo Metro or Suzuki around? Obviously, some people don't need the power or don't care about it.

Why do people drive diesels? Maybe to be different. Maybe they like the noise the engine makes. Diesels get attention (what's that coming down the road?) Reliability--you can drive through water with out the ignition system cutting out. There are lots of reasons. Perhaps they don't appeal to you since you have different needs that are than diesel drivers.

I am not going to stoop to responding to 1991 560 SEC's ignorant comments. The guy should stick to discussion groups that are more in line with his own interests. If he is bored with sitting at home and looking straight ahead all day, then I feel sorry from him. If he would like some advice on discussion groups and web sites that might be more appropriate to captivate his interests, I am sure that many of us can suggest some.