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  #16  
Old 10-27-2001, 12:15 PM
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Location: Columbus Ohio
Posts: 709
well I guess the pic posted above reminds me of something that I have seen posted here....."nothing will cost you more money than a benz that has not been taken care of"......

in regard to the price spread on cars on cars for sale...I have seen that a lot also....even larger spread on the 129 and 140 vehicles...some people are actually getting above book for their cars....so I guess it does pay off to maintain your vehicle


Warren
1992 300SD 126K
Columbus Ohio
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  #17  
Old 10-28-2001, 03:54 PM
Dennis
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350SDL

I may be a "lucky" one, but my 1990 350SDL has 145,000 miles on it.. it runs like new, no oil consumption between 4,500 mile changes, great compression, and purrs like a kitten.
There are a few things on this engine that I've come to believe based on what several seasoned Benz mechs have told me and what I've heard on the various discussion threads.
1. This engine is likely more sensitive to overheating than any other of the Benz diesels. The thinner cylinder walls will overheat quicker when water gets low and also there is less gasket space between cylinder and water jackets. All the mechs I have talked to about this engine said: "Don't let it overheat!" Two of them told me they suspect the bent rods may have been caused by hydraulic lock. Keep in mind, "overheating" doesn't mean when the temp goes up to 100 on a long hillclimb, but rather severe metal-bending heat.
They suspect a scenario like this... Engine overheats, (not catastrophically) gasket integrity fails when the aluminum head warps a little.. then when you shut off the engine the pressure in the cooling system causes water to seep in to the cylinder.. maybe not much.(doesn't take much!!) Next time the engine starts... well, you can imagine. Something has to give and it will be the piston rod.
2. Another issue with this engine is rebuilding.. there are some things about this motor that are unusual when reassembling it. (most important is the torqueing of the head) I think I would only go with a factory short block rather than trust anyone, even a dealership, with a complete rebuild.
3. My engine has always been run on synthetic oil.. this may not be a major issue, but I would think there would be some additional margin provided at high temperatures if things get stressed.
4. If anyone is worried about the pure strength of these engines I can only offer that I have planted my foot to the floor in my SDL in the middle of the Bonneville Salt Flats... she went right up to 114 mph and stayed there for 20 miles. No ill effects noted.. it ran a bit warmer, but that was it.
5. The issue of "oval shaped" cylinder wall wear has surfaced. When Benz engineers increased the stroke of this engine they did not lengthen the rods. (would have necessitated a taller block) This increases the angular displacement of the rods at mid-stroke... thereby adding to the side-loads on the cylinder walls when under power. While MB may have not violated any normal tenants of engineering by doing this, they may have pushed it to the limits when considering that these engines would be subjected to a wide variety of owners, lubricants, shoddy maintenance, occasional overheating, etc. While the venerable 617 engines were way overbuilt and could handle some rough treatment, there probably isn't as much margin here.
These are suppositions on my part of course, but we're left with nothing else since MB has been totally silent and non-forthcoming on this issue. On the good side.. these 350SDLs are an incredible marriage of comfort, economy, uncluttered elegance, and almost decadent spaciousness. The earlier 126s have the same room, but the driveability on the 350s is much better.. almost no turbo lag, a lot faster off the line and slightly better mileage. It's a shame that the model is tainted with this gremlin.
Dennis
Arvada CO
1978 300CD 286,000 mi
1990 350SDL 145,000 mi
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  #18  
Old 10-28-2001, 03:57 PM
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Location: Old Lyme, Connecticut
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Unhappy My 1991 350SD Saga

I have had first hand experience with one of these cars, and it was after having driven Diesel powered MB's for twenty years. I was so taken with the robustness and quality of the cars I had that preceded it, I took for granted this car would be equally bullet proof. I bought it from the local dealer, with 75,000 miles on it, with a Starmark Warranty from Mercedes-Benz. When I bought it I had the compression tested, just out of force of habbit, and it checked out in like new condition. No smoking, no odd idle and no unusual oil usage for 6 years and another 88,000 miles. My normal oil change intervals were 3500 miles, and the oil level light never came on. Then, all of the sudden, with the car at about 161,500 miles, it started idling a little lumpy and smoking. I figured the valve seals were gone, as I have experienced this with other cars, and scheduled a trip to the shop at the dealer where I bought the car. I once had a garage but gave it up a long time ago, and now do not start engine work in winter months. This was last December.

Once they got the car they did some compression checks and let me in on the bad news. Compression dry was bad on two cylinders and wet was good on all of them. They were convinced I needed a rebuild or a new engine. With the head off they had me in the shop and showed me the two cylinders with bent rods don't come up to the same height as the rest. Bent rods, meant a rebuild or new engine, and they convinced me I would be happier if their mechanic rebuilt the engine as he was very experienced and so on. Well, I have been a customer there for over twenty years, and they have an excellent shop. The mechanics are honest and very competent, based on personal experience, so I had the engine rebuilt.

I asked what the failure mode was and if my driving or maintenance could have caused it. I was assured a number of times that nothing I could have done would contribute to the bending of the rods.

So I looked into the issue and found this site, among others on the internet and started asking around. I concluded the problem is an engineering error; basically something that sees high cyclic stresses like a connecting rod has to be designed for an infinite fatigue life. For a variety of reasons the design and manufacturing tolerances for this part conspire to make the population of connecting rods fall into two categories, those that have an infinite fatigue life, and those that do not. I had four rods from the first category and two from the latter. Those that have less than the infinite fatigue life can be woefully short, or near but not there, and will fail sooner or later depending on operating conditions. My guess is if you do not see a failure early in the engine's life, the combination of actual tolerances and loads you subject the engine to are helping put the failure off. When they fail it is not a gradual thing, as at 3,000 or so rpm, the cycles accumulate rapidly, and you can go over the limit at any moment. The consequential damage, ovalizing the cylinder bore and smoking, are things you do notice over time, but by that time the damage is done. There is no detecting this ahead of time and doing preventive maintenance to keep it from happening.

Anyway, this really got to me. Most automobile owners and operators would think a car with 162,000 miles on it might well be coming up on an engine swap or overhaul. But not a long time Mercedes-Benz Diesel owner and operator. I bought the car to drive for twenty years and several more hundred thousand miles. I never considered it might have a buried engineering defect in the engine on a critical part like a connecting rod. When I asked if my rebuild engine had new parts with suitable design and manufacturing corrections, I was not given much assurance by the service manager that it had. This got me even more irritated, as I was imagining another random failure or that Mercedes-Benz was putting a gag order on the service manager to avoid getting dragged in to this to pay for an obvious and blatant engineering error. I think even the lowliest Hyundai or any other car has connecting rods with an infinite, calculated, fatigue life considering the manufacturing tolerance range.

After 10 months the car has started smoking again, although the oil usage is still such that I never use more that half a quart in 3,500 miles. I was told this time it was the turbo leaking oil past the seals into the exhaust.

While I never got much satisfaction from the service manager, the sales department did put up a fight for me, and I ended up trading the car in (based on a very fair allowance considering the investment I have made in the rebuilt engine) for a 1998 E300D TurboDiesel, with 40,500 miles on it last Tuesday. The new one has been around New England the last week and is really a remarkable Diesel automobile. I have mixed feelings about how sophisticated the car is, as when this one gets twenty years old, I will be pretty creaky if I am still around, and there seem to be a lot of electronic gizmos likely to need to be fixed by then. But it runs and goes like no other Diesel. What if it had a 5 or 6 speed manual, and simple A/C, manual seats, manual sunroof, and even manual wind up windows?

If anyone reads this to the end, and wonders what that was all about, the message is, I would stay away from that model Mercedes Diesel. It seems any other one is fine. Jim
__________________
Own:
1986 Euro 190E 2.3-16 (291,000 miles),
1998 E300D TurboDiesel, 231,000 miles -purchased with 45,000,
1988 300E 5-speed 252,000 miles,
1983 240D 4-speed, purchased w/136,000, now with 222,000 miles.
2009 ML320CDI Bluetec, 89,000 miles

Owned:
1971 220D (250,000 miles plus, sold to father-in-law),
1975 240D (245,000 miles - died of body rot),
1991 350SD (176,560 miles, weakest Benz I have owned),
1999 C230 Sport (45,400 miles),
1982 240D (321,000 miles, put to sleep)
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  #19  
Old 10-31-2001, 12:08 PM
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Join Date: Feb 2000
Location: Columbus Ohio
Posts: 709
Well ,

I have a MB rebuilt ,dealer installed complete long block assembly....I have heard that the rods and head are of different design ...according to the tech that installed it.......
In regard to the guy above who had his engine rebuilt at 162K.......it seems like whomever did your work may not have been the best tech......also if it was a dealer who did the work I would have contacted the MB zone rep and voiced my opinion.....the spead of money is about 1500 from usuing a new MB shortblock and using a rebuilt longblock...and with the longblock you get a 48mo 50K warranty...that to me is a no brainer...in regards to driveability this engine represents a vast improcement over the 80's diesels...and of couse the 98-99 E300 Turbodiesel is again another improvement in driveability

Warren
1992 300SD 126K
Columbus Ohio
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  #20  
Old 10-31-2001, 06:58 PM
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The cost spread for the job I had done was over $3,000. I got a firm fixed quote for the job before I started, and at the time the rebuilt engine was not from Mercedes in Germany, but a supplier that does this work for MB, which I believe is out of California. The engine alone was over $9,000. It made no difference to me that the rebuilder was not a Mercedes-Benz owned outfit as it came with MBNA's 48 month or 50,000 mile warranty. The big and deciding difference for me was $3,000 plus. I was confident the dealer's mechanic could handle the job at the time, and still think the work he did was and still is fine. I was unaware the turbo was about to start leaking, and, if the pseudo factory rebuilt engine long block comes with a turbo, I might have been better off to have spent the extra $3,000 plus at the time.

But that is all water over the dam, as today I am enjoying my E300D TurboDiesel quite a bit more than the 350SD - it is much more agile and spirited and gets 34 mpg vs 26 to 27 mpg. So, I am happy with the way it turned out, but disappointed that Mercedes sold such a flawed car.

The point of my saga was to advise the person considering the 350SD that the engine is most likely a time bomb. And it is between $6500 and $10,000 to get it fixed when it goes off. So, if you are considering spending a sizeable chunk of change on a car, you might just be better off buying something else. Jim
__________________
Own:
1986 Euro 190E 2.3-16 (291,000 miles),
1998 E300D TurboDiesel, 231,000 miles -purchased with 45,000,
1988 300E 5-speed 252,000 miles,
1983 240D 4-speed, purchased w/136,000, now with 222,000 miles.
2009 ML320CDI Bluetec, 89,000 miles

Owned:
1971 220D (250,000 miles plus, sold to father-in-law),
1975 240D (245,000 miles - died of body rot),
1991 350SD (176,560 miles, weakest Benz I have owned),
1999 C230 Sport (45,400 miles),
1982 240D (321,000 miles, put to sleep)
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  #21  
Old 10-31-2001, 10:46 PM
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Join Date: Feb 2000
Location: Columbus Ohio
Posts: 709
Did you have a complete rebuild?........list prices for parts of a new short block are $6000....with a 12 mo warranty and $8600 for a complete rebuilt long block is $8600 ...with a 48 mo 50K warranty.....so if you paid over 9K for a long block you might want to hava a discussion with your parts supplier.....my dealer even discounted the part to about $7500.00 as to try to get under what the warranty was willing to pay...in regard to the price spread I was quoted 3K for labor for the short block and 1500 labor for the block as the long block was simply a drop in procedure where as the short block was almost a complete teardown.......for the extra $1500 it was worth the extra 3 years of warranty as well as the updated/improved parts...as well as the improved resale value.....my thoughts were I would get the my moneys worth in the warranty and resale issues..as resale of my car is a big issue...It seems that the early 140 diesels are still bringing a decent buck in looking at the online ads..
.by the way I agree with you about the E300 Turbodiesel...great car...a good friend in Texas has one...

Warren
1992 300SD 126K
Columbus Ohio
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  #22  
Old 11-01-2001, 12:03 AM
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Join Date: Jul 2001
Location: Old Lyme, Connecticut
Posts: 3,596
I was quoted the job for the long block replacement as a $10,400 job complete, and the other job as just under $7,300. Both jobs were burdened with removing the head to examine the engine and verify it needed to be rebuilt. I am not familiar with what a complete rebuild would be, but I think what I got was pretty thorough. The head was disassembled, cleaned and parts inspected because I insisted on it, and witnessed some of it. Everything came out ok, and the valves, guides, cam, etc. were all reused as-is. Did get a new chain, tensioner and rail, as well as pistons, rods and rings, bearings and lots of small stuff. The block was bored and honed, the pistons ordered to match, and the crank was inspected and re-used.

I was quoted a 15%, and on some parts, 20% discount with my MBCA membership. I also got a discount of 10% on labor. The long block "factory" rebuild was not discounted as it was not available through Mercedes, it had to be ordered from the agency doing the work. The prices for the two options were determined ahead of time, and I think the shop might have been slow at the time, so they may have steered me in the direction of having the engine rebuilt in house.

That the engine was rebuilt by the dealer was never my problem. My problem was that there seemed to be a design/manufacturing problem and Mercedes was not willing to step in and supply parts or labor, or something to acknowledge they put an engine into production that was flawed by their and the industry's standards. Parts like pistons, rods, crankshafts, blocks, heads, etc. just don't suffer fatigue failures if they are designed and built to well established standards.

I only ran it with synthetic oil (either Mobil 15W50 or Castrol Syntech 5W50) for the 100,000 miles I drove it, which seems to pay off. Other than the intake the engine was really clean. The intake had a lot of crud from passing oil and oil vapor from crankcase blowby accumulated.

By the way, does the "factory" rebuilt engine come with a new turbocharger?

The saga may be over but it still gets my craw that I got a substandard car from Mercedes. Jim
__________________
Own:
1986 Euro 190E 2.3-16 (291,000 miles),
1998 E300D TurboDiesel, 231,000 miles -purchased with 45,000,
1988 300E 5-speed 252,000 miles,
1983 240D 4-speed, purchased w/136,000, now with 222,000 miles.
2009 ML320CDI Bluetec, 89,000 miles

Owned:
1971 220D (250,000 miles plus, sold to father-in-law),
1975 240D (245,000 miles - died of body rot),
1991 350SD (176,560 miles, weakest Benz I have owned),
1999 C230 Sport (45,400 miles),
1982 240D (321,000 miles, put to sleep)
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  #23  
Old 11-01-2001, 09:56 AM
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Location: Columbus Ohio
Posts: 709
The longblock did not come with a new turbocharger.....a rebuilt unit was an extra 2500-3000....mine was checked out and met MB specs so it was not replaced...the $7300 you paid for a rebuild sounds like an aggressive price ......did they shortblock your engine?...if do was the part new?......at the time of my engine replacement...the price was 6000 for abrand new MB shortblock and 40 hours worth of labor to repair.,,about 9K...or $8600 for a long block and 20 hours labor...about 10K...and the latter also came with a 48mo 50K warranty..parts and labor
MB has helped some people out with this problem depending on the mileage of the car...there was one guy who I had contact with who got a complete longblock and turbocharger...total bill was $13K...he paid $6500 and MB covered half...car was a 93 with about 75K miles.....I have had several long "chats" with my MB zone rep about the dissappointments with my car...not only the engine issue...but the evaporator core,which has been done twice at $2800 a pop...once with original owner and once under my ownership..various electrical issues...closing assist pump,climate control push button,blower resistor...etc..etc..etc

to throw in a funny fact a good friend intown who has a 1992 400SE was told by the dealer that they love 140's as the repairs are so expensive the service revenue makes up the major portion of their sales


Warren
1992 300SD 126K
Columbus Ohio
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  #24  
Old 11-01-2001, 04:42 PM
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Location: Old Lyme, Connecticut
Posts: 3,596
Warren,

I got no official assistance from Mercedes-Benz, but I did negotiate a fixed price with some assumptions on what would be replaced. The cost grew a few hundred dollars, and when I went over the job with the service technician to understand why it grew he pointed out I got a very good deal, especially on labor. I kind of believed him but also suspected I was being manipulated. In the beginning I was not all that confident I wanted to fix the car as with 162,000 miles, by the book, it was not worth much more than the engine rebuild was going to cost.

The warranty for the extra time and miles did not seem like it was such a good bargain either as I had had a Starmark warranty on the first 25,000 miles I drove the car when I bought it and it was 100% trouble free. In fact, I fully expected that if the engine ran 12,000 miles and had no failures, it would run 300,000 miles and none of the things that were included in the extended warranty would fail. I still thought the bent rods were an anomaly. At the time I was so unaware of the rod fatigue issue I was presuming the engine would not need six new rods if only two were bent. The mechanic insisted he should replace them all and did. Looking back I should have been suspicious. Anyway the paper study comparison of cost before starting the job showed a difference of more than $3,000, so I opted for the rebuild by someone who's face I looked into when he said he would do the job right. Like I said I was not unhappy with what the shop did, just that it happened at all, and then the turbocharger seals started failing, and the bill for that was just over the top.

The engine was disassembled and the block sent to a local machine shop to be measured, the feasibility of boring to fit the apparently available larger sized pistons (I think I was told they come in a couple of diameter increments larger than stock). Once that was established, which took a few days, they ordered pistons. When the pistons arrived the original block was rebored and honed to suit. They did some checks for cracks and the like before boring, but there was no reason to suspect there were any other hidden forms of damage. The engine was never overheated or run out of oil so there were no other effects to report back to me. I think if there had been a trace of owner/operator abuse apparent I would have heard about it as there was a definite interest in expanding the scope of the job on the part of the shop manager.


Since the job took nearly 5 weeks and I was interested, I stopped in and checked the progress out periodically. I know the mechanics there reasonably well and was invited into the shop to see some of the stuff for myself. While I did not check serial numbers of parts, if a new block was needed I am certain I would have been charged for one, even a used one. Once the block came back from the shop and all the parts were in, the reassembly was pretty quick.

The next problem that "broke the camel's back" was the turbocharger leaking oil and the cost to repair it, estimated at around $1,500 for the part (MBCA discount again) and a large dollar value, near $700 if I remember correctly, to install it. By the way, I found a source for the rebuilt turbocharger from someone on this forum in another thread, where they are $475 with a core charge. If you are interested I can try to dig it up. I was considering doing the job myself until I concluded I was not interested in taking the engine compartment apart to get to the turbocharger. On the E300D TurboDiesel the turbocharger is right out in the open, something I checked when I was shopping the lot.

I am optimistic the newer car will be less challenging to the do it yourself type, and will skip the built in engineering error of the 350SD. The space under the hood is mysteriously greater for the smaller car, with a similar sized engine. And once again I have a few years and up to 59,000 more miles of Starmark warranty protection with the car to make sure the car is ok. It continues to amaze me with its performance and agility. Jim
__________________
Own:
1986 Euro 190E 2.3-16 (291,000 miles),
1998 E300D TurboDiesel, 231,000 miles -purchased with 45,000,
1988 300E 5-speed 252,000 miles,
1983 240D 4-speed, purchased w/136,000, now with 222,000 miles.
2009 ML320CDI Bluetec, 89,000 miles

Owned:
1971 220D (250,000 miles plus, sold to father-in-law),
1975 240D (245,000 miles - died of body rot),
1991 350SD (176,560 miles, weakest Benz I have owned),
1999 C230 Sport (45,400 miles),
1982 240D (321,000 miles, put to sleep)
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  #25  
Old 11-01-2001, 05:28 PM
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Join Date: Feb 2000
Location: Columbus Ohio
Posts: 709
Thanks Jim for the info......I know that this engine situation can be very frustrating....in Columbus Ohio where I now live there are two MB dealers....neither one of which is very big, compared to the dealers I used to go to in Dallas Texas...so being that MB only sold about 3,000 diesels 140's in 3 years of production it just so happened that even in Columbus there was a guy at the other dealer who was having a new engine installed as I was having my work started...I had a long heated conversation with the MB zone rep and I questioned the fact that 1) there are probably only about 3-4 diesel 140's in Columbus and 2) two of them were having new engines installed!!.......he said something about US fuel quality or something....
anyway the other gentleman had about 150K miles on his car and according to the Zone rep the dealer was doing the job at cost since they had sold and serviced the car its entire life....but MB,he said,could not offer anything in terms of goodwill,on a car with that mileage....he was somewhat flippant with me as he wondered why I was so concerned about a repair I really wasn't going to pay for.....
At this point my engine runs fine...but who knows I may get rid of the car before the 50K warranty runs out........I have heard that the new engines have never had recurring problems..but who knows.....my car has been a maintenance nightmare...the reason that extended warranties cost so much I guess?...somewhere between $23-24K worth of total repairs...my tech at the dealer jokes with me that I have a brand new car because of the extensive list of work he has done......I plan to keep it for a bit as much of the repair work is still under MB parts and labor warranty..but after that I will have to reevaluate the situation


Warren
1992 300SD 126K
Columbus Ohio
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  #26  
Old 01-29-2005, 01:35 AM
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Unhappy 350 fear factor

More old 350 data.
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  #27  
Old 01-29-2005, 01:44 PM
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Run these on Bio-Fuel

I just got mine. 1992 300SD.

I'll power it with Bio-Diesel to prolong the engine life.
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