question Diesel or Petrol

[Royston59]

I know its been done to death but its always a facinating topic for the answers it throws up........

Do Diesel engines out last Petrol engines and (if so) why?

We are not talking specifics here eg machinery in a commercial sense, simply Cars in general...

Cheers
R

 

[whitenemesis]

Mileage or years?

 

[Royston59]

Mileage or years?

ah now there's a thought....I guess it must be mileage as I have seen a lot of engines out last the car that surrounds them...
Cheers

 

[peterwhayward]

without a real study done by any body of people its a difficult question to answer. i would think that most peoples perception is that diesels do last longer, but.......................that would only be the case if both cars were driven in the manner that they were intended with equal care given to both in terms of servicing etc. In real terms if the above was the case I would think that the diesel would do more miles if used for sustained distances (as intended), but last longer?, i'm not so sure.

 

[st4]

Generally a diesel will tend to outlast a petrol but it depends engine by engine

 

[television]

I am sure there is no difference in the 2 mileage wise, there is no reason for them to be any different from each other, technically the petrols should win as the diesels run with a higher compression

 

[Silver_Star]

But diesels don't rev as high therefore less wear will occur, particularly when cruising.

 

[television]

But diesels don't rev as high therefore less wear will occur, particularly when cruising.

Debatable as thrust can cause more wear and my CL500 cruises at 70 at just under 2k rpm

 

[S80]

Just a quick search on autotrader.co.uk for cars over 10 years old reveals:

3854 diesel
21873 petrol

 

[GeeAy]

I'm not a an automotive engineer, but my feeling is there are a number of areas which lead to an Oil burner being more robust. Firstly the componants are built like brick outhouses to contain the pressure required to combust and the pressure generated as BMEP (Break Mean Effiective Pressure which relates to the motive force generated). Secondly the high BMEP means the engine runs at significantly lower revs thus reciprocating wear over time is reduced. or something like that. But lower revs and stronger components probably covers it.

 

[peterwhayward]

Just a quick search on autotrader.co.uk for cars over 10 years old reveals:

3854 diesel
21873 petrol

Thats because nobody sells a diesel thats just been run in.....where as petrol, they all want to get rid of.

 

[Silver_Star]

Diesel is an oil, where as petrol is a solvent, which must have an effect on longevity. Diesel also has a lower combustion temperature.

In reality in modern cars, the engine will still be ticking when the rest of the car is ready for the scrappy.

 

[S80]

Thats because nobody sells a diesel thats just been run in.....where as petrol, they all want to get rid of.

Or alternatively because the high cost of diesel ancillary failures is enough to write off an older car?

 

[Silver_Star]

Let's not forget diesel wasn't as common 10+ years ago. They didn't used to put the power out they do now in comparison.

 

[GeeAy]

Or they rattle so badly from new that you dont realise they've been knackered for the last 100k so keep driving it..

 

[S80]

They didn't used to put the power out they do now in comparison.

So were probably more reliable

 

[Silver_Star]

So were probably more reliable

Without a doubt they were more reliable.....but were talking about longevity here

 

[television]

Let's not forget diesel wasn't as common 10+ years ago. They didn't used to put the power out they do now in comparison.

And at what cost, port motors, flaps, DPF's pumps, injectors, compressors, they are not like the old simple 603 engines, they can cost a lot of money to keep them going

 

[television]

Or they rattle so badly from new that you dont realise they've been knackered for the last 100k so keep driving it..

And the horrible smell to go with the noise

 

[Sue new MB owner!!]

I think Diesels sound like Taxi's .... nowt wrong with Taxi's ... but...

Petrol engines just.... welll... sound better!!! ..... sorry no tech blah blah from me!!