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Why do diesel engines last longer??
68AutoBug - July 15th, 2003 at 01:46 AM

[size=5]Why do Diesel engines last Longer...? Is it the OIL used? the FUEL used? or the combustion type used? or a combination of them all? Many older people used diesel engine oil in their petrol engined cars back in the 60s & 70s , but these days I don't believe there is much difference, as most good Petrol engine oils can be used in Diesel Engines too. I believe ALL Engine Oils are Detergent oils these days...[/size]:bounce:bounce:bounce:bounce:bounce:bounce

[Edited on 14-7-2003 by 68AutoBug]


Stanley - July 15th, 2003 at 08:02 AM

Don't know but my '86 toyota hilux has just clocked 300,000 km's and is still going strong.:thumb:thumb


Bugged Again - July 15th, 2003 at 08:34 AM

Anyone put a diesel in the back of a baja?

if they are in all the hard core 4wds why not a veedub?


Secoh - July 15th, 2003 at 08:41 AM

the more a motor revs, the faster it wears out is basically the short answer.

as most diesels dont get revved over 3000rpm wear is kept to a minimum.

also the partially burnt and unburnt fuel that gets into the sump as blowby is not as acidic as the blowby from combusted petrol.

i suspect the reason why they havent been stuck in VW offroaders is gearing and the fact that they weigh a ton. :)


JETTABOY - July 15th, 2003 at 11:14 AM

I think it comes down to how you look after it!...Regilar servicing is much more necessary....My old jetta diesel finally died, " but still didnt stop" with 475000 on it!


Andy - July 15th, 2003 at 12:27 PM

A combination of things really.
Most diesels we see here are truck and commercial vehicle based. Diesels are made much stronger for the high compression ratios they see (double a petrol motor!), this also by design leads to long strokes and heaps of torque they are notorious for. A combination of that and a more industrial type application so they are over designed and weight is no longer an issue will give much better life. Also they run much cooler, so oils are much less stressed in them, so the lubrication in the critical areas is also much better.
I don't know about all the light weight high perfomance diesels now common in Europe, but I'd expect they will not last as long as the crude heavy diesels motors we have seen in the past.

I'd still love to fit a Deutz air cooled diesel motor in the Kombi one day.

Secoh what you say is partially true. Don't forget low RPMs means high torque to get some power which puts a lot of load on bearings, crank rods, etc.
:thumb


Baja Wes - July 15th, 2003 at 12:57 PM

What Andy said is right. Over-engineered and over-weight. They also have a lower rpm range which helps them live longer (like Secoh said).

Petrol engines can live just as long if they are driven in a similar manner. Look at your average ford falcon taxi, those things get incredible engine life.

Diesel oils have more detergents in them, don't think that'd help much. Their fuel is also an oil (diesel oil) which probably lubricates the cylinder walls, as opposed to petrol which washes the oil off the cylinder walls.

Quote:
if they are in all the hard core 4wds why not a veedub?

Well most hard core 4wd's actually run petrol motors. If they are mud runners then sometimes people prefer the diesel because the lack of electrical components make them waterproof. 4wd'ers also want low down torque.

Hard core VW offroaders don't need low speed torque so much. But the weight is the main problem. They just don't make all alloy diesels. They like cast iron.

[Edited on 15-7-2003 by Baja Wes]


Brad - July 15th, 2003 at 01:08 PM

mmm without getting of teh topic to much I would say yes to what Wes said but no to "Well most hard core 4wd's actually run petrol motors. "

You will find most hardcore 4WD's are in fact diesel. This is due to several facts, non of which have to do with engine life, mainly:
- don't get effected by water ( not talking about in tank.
- diesel is availible anywhere, petrol is not
- Much better reliability, much simplier engine, yes this is changing with the intro of electronic injector pumps rather than manual.
- they are much better than a petrol engine in relation to drivable power ie torque.

My next 4WD will be a diesel, and I would have one in my buggy if they didn't weight so damn much.


Baja Wes - July 15th, 2003 at 02:45 PM

I am talking Hard core 4wder's, which most will use high powered petrol motor's cost the diesel's just don't have the HP. One of the most extreme 4wd's I have seen in Aust was running a 454 V8.

4wd people that tour australia, own farms, like to drive through rivers, etc will like diesel's, but I wouldn't call them hard core.

Hard core 4wd'ers will run a mix of either engine, but it's certainly not a case of "diesel only" in the hard core scene. You should know that better than anyone Brad :P

Offroading in a VW is more like getting a trail bike up a hill, rather than a 4WD up a hill. You wouldn't want a diesel trail bike :D


Bugged Again - July 16th, 2003 at 12:14 AM

when i said hardcore i meant the guys who travel all over oz on any roads/tracks who nee dto worry about being in the middle of nowhere with petrol stations non existant.

Not the guys that would run the rubicon trail or go into the bush on the weekend and try to drive up the steepest most rutted hill they can find. or in the middle of the night in brisbane in some bush somewhere

they had a good show on bris31 about these guys a few months back. (spose these are the real hardcore guys)

So basically it comes down to weight for not using diesel motors in vws


The_Bronze. - July 16th, 2003 at 01:53 AM

Yeah - Been there asked baout that. A shame really. I love the sound of an idleing diesel engine warming on a crisp cold morning.


azz - July 16th, 2003 at 05:34 PM

68AutoBug
Why do you type so largely?


Adam_C - July 16th, 2003 at 05:41 PM

[size=8]TO STIR SHIT???[/size]
am i right???
lee?

:P::P:P


amazer - July 16th, 2003 at 06:24 PM

maybe he likes his posts to stand out? Maybe his screen resolution is so high the only way he can read his posts is to up the font size. I dunno, but better large and black than in some other colour thatwe all have trouble readinglike the old lee used to do.


amazer - July 16th, 2003 at 06:27 PM

lucky taxis dont have the GenIII V8. Some of them are having trouble lasting 40K let alone 400.