Hopeless Mercedes Diesel Engines

[sowlerthjh]

I bought a W124 300D about two years ago in the belief that it would last for ever. It had 179,000 miles when I bought it, and has now done 207,000 miles.

However, earlier this week, I was driving on a motorway when I noticed smoke (white) coming from the exhaust pipe. When I stopped by the side of the motorway, I noticed that the engine was running extremely roughly. It has since been taken to a garage who say that there is a cylinder blocked (sixth cylinder?) and that to fix it would cost at least £800.

1. Is this a common fault? I thought these engines were meant to last much longer than 207,000 miles.

2. Will it really cost £800 to repair?

3. The car is in excellent condition otherwise (1990 model, auto), what is the best course of action?

I am not impressed, having heard so much good about Mercedes diesel engines.

Any advice will be appreciated.

Many thanks,

SOWLERTHJH
07801 227594

 

[panason1c]

Could be something as simple as head gasket failure which can (and does) occur on ANY manufacturer's engine whether diesel or petrol....the white smoke would be coolant entering the cylinder via the failed head gasket and exiting the exhaust as steam.

207K is a lot of miles and it is not unreasonable to expect to have the occasional problem at that mileage.

 

[robparker]

Just because its a mercedes diesel doesn't mean its invincable. I sold my 190d with 220,000 miles and it was running as new... but it had also been religously maintained throughout its life with oil and filter changes every 3-4k miles. i agree that yours sounds more like a head gasket..

 

[robbo]

I think at that mileage and age, expecting any car to be flawless is asking bit too much i'm afraid.

 

[Hibbo]

I think you are being a wee bit harsh calling an engine 'hopeless' just because it developes a problem after 16 years and more than 200,000 miles.

The om61x and om60x are excellently engineered and extremely robust and reliable engines but do need frequent oil changes.

As for a 'blocked cylinder', I have no idea what he is on about and believe he may be trying it on somewhat. As others have said, it bares all the signs of a blown headgasket. Run the engine with the top of the expansion tank off, give it some revs and see if it blows anything out of it. You could also pressure test cylinder 6. I wouldn't get this garage to do any work for you if he is trying to charge you £800 to fix a made up snag, without checking the obvious things first. (I stand to look foolish, but I have never heard anyone refer to anything remotely like a blocked cylinder)

 

[panason1c]

I have never heard anyone refer to anything remotely like a blocked cylinder)

Me neither!

 

[Rory]

I think you should contact Mercedes customer services and express your disappointment, and ask for a contribution to the repair cost. Contact What Car too.

 

[Sprint'n'Go]

I think you should contact Mercedes customer services and express your disappointment, and ask for a contribution to the repair cost. Contact What Car too.

Very cheeky Rory.

All-bran or prunes should fix the blocked cylinder a treat???????

 

[Parrot of Doom]

Blocked with what, a Squirrel?

Agree with the above comments. 207 000 miles is not 'hopeless'. I bet if you looked after it, you'd get double that.

 

[sowlerthjh]

Perhaps the term was not "Blocked Cylinder", but something to do with the injector pump has failed, which means that a cylinder is not working as it ought to. I have been advised that it is possible to have a compression test done, but that it is not worth it.

The point I am making is that it is often said that Mercedes diesel engines go on for ever. I have looked after it, with servicing every 6,000 miles. When I bought it, it had a full service history, mostly from a Mercedes dealer, but some from a well-respected independant dealer.

I have had other cars in the past which have done high mileages, including an Astra which managed 300,000 miles before rust and general problems finished it off. I also have a 1997 Peugeot 406 (not usually known for reliabliliy) which from new, other than a head gasket, has had very few problems, and currently has 247,000 on the clock.

Are Mercedes cars REALLY any more reliable and long-lasting than other makes?

 

[robbo]

Unfortunately no, IMO.

 

[rio678]

most probably cylinder head gasket , my supra did that to me, white smoke out the back and running very roughly, cost about 500.00 to repair, which is reasonable i think.

 

[Parrot of Doom]

Are Mercedes cars REALLY any more reliable and long-lasting than other makes?

On balance I'd say yes. They're generally better designed and better engineered than other cars, which is why they're more expensive.

Its my 8th car, I've done bits and pieces on all of them, and this is easily the best designed car I've owned. You can normally tell when you start taking things to bits, and I've seen no really obvious signs of cheapness when I've been pulling stuff off mine.

Nothing's perfect though. I still have yet to sort out my wheel balance issues.

 

[Blobcat]

On balance I'd say yes. They're generally better designed and better engineered than other cars, which is why they're more expensive.

Its my 8th car, I've done bits and pieces on all of them, and this is easily the best designed car I've owned. You can normally tell when you start taking things to bits, and I've seen no really obvious signs of cheapness when I've been pulling stuff off mine.

Nothing's perfect though. I still have yet to sort out my wheel balance issues.

I could not agree more, I recently took out the gear lever surround on my car and the way that it all comes apart shows the quality of the original engineering.

 

[jberks]

Are Mercedes cars REALLY any more reliable and long-lasting than other makes?

I'd have to say yes too.
Ok - engines can go on for 300k or die at 150k and to be honest that applies as much to a Vauxhall as to a Merc. I suspect the wear on the Merc engine will be a bit better but with proper maintenance there's bugger all in it. Case in point was my Dad's Cavalier. After 250k it was sweet as a nut. However, the bodyshell was so sloppy it felt like it was held together with rubber bands. Everything rattled and bounced around, the seat had been welded a couple of times and it was all a bit smelly. Sure it was still running fine but not a pleasure to sit in. Compare to a Merc of a similar vintage and the differences become obvious.