Diesel engines - the good & the bad

Life Cars & Motorcycles
1

Hi all,

I’m considering buying a new pickup truck. I’ve got to act quickly if I want to take advantage of the government’s NT$30,000 bribe that expires this year.

I’ve considered a number of models. One thing I haven’t looked at yet are diesel engine vehicles. I’m not sure what’s available, but I’ll stop by Mitsubishi later today and ask. I don’t want anything too big, which could be a problem - mostly, I see the Canter on the roads, which is 3.5 liters, about double the size I’d need. I have seen some older Delicas with a 2.0 liter engine, but I’m not sure that they’re still being manufactured.

Any opinions out there on the wisdom of owning a diesel powered vehicle? I know that performance isn’t as good as a gasoline motor, but fuel economy is supposed to be better. I really intend to use it as a truck, not as a family vehicle. I live on a farm and need a working truck.

best regards,
DB

2

[quote=“Dog’s_Breakfast”]Hi all,

I’m considering buying a new pickup truck. I’ve got to act quickly if I want to take advantage of the government’s NT$30,000 bribe that expires this year.

I’ve considered a number of models. One thing I haven’t looked at yet are diesel engine vehicles. I’m not sure what’s available, but I’ll stop by Mitsubishi later today and ask. I don’t want anything too big, which could be a problem - mostly, I see the Canter on the roads, which is 3.5 liters, about double the size I’d need. I have seen some older Delicas with a 2.0 liter engine, but I’m not sure that they’re still being manufactured.

Any opinions out there on the wisdom of owning a diesel powered vehicle? I know that performance isn’t as good as a gasoline motor, but fuel economy is supposed to be better. I really intend to use it as a truck, not as a family vehicle. I live on a farm and need a working truck.

best regards,
DB[/quote]

Diesel certainly has benefits over petrol power, but the question is whether you will require the advantages, or suffer the drawbacks more perhaps.
Diesel generally offers more torque than petrol engines, so for pulling heavy loads, the diesel is your engine. Also because diesel engines tend to be some form of direct, or semi direct injection, less of the fuel is wasted because of inefficient induction and so you get a more complete burn, resulting in the harvesting of more power per droplet of fuel, meaning greater economy than a typical Otto cyclic petrol engine. Diesel is cheaper to produce than petrol, requiring less refining and can often be found at cheaper prices. Those are some of the advantages of diesel.

Disadvantages of diesel are numerous. Diesel tends to be the dirtier fuel, more so than petrol, but the dividing line between diesel and petrol for most people comes down to cost, more often than any other factor. The costs is often the misunderstood concept when deciding between one type of vehicle over the other. Here are some of the factors you will have to decide for yourself.
Diesel engines are often more expensive to produce than petrol engines due to the necessary precision of their components and the additional strength requirements of their internal components. This often means than diesel vehicles are a higher purchase price. Service intervals of diesel vehicles generally spaced closer together than their petrol equivalents, meaning more expensive service costs are a factor.
Diesel is a dirtier fuel and coupled with engine components under greater stress can reduce the economic life expectancy of a diesel engined vehicle. Check reliability factors of the vehicle you are considering and expected useful longevity if possible. Diesel fuel in some areas has been made artificially expensive to try and dissuade people from owning more polluting vehicles. This will perhaps change in time as vehicle design and pollutant levels improve, but in the meantime produces yet another factor when considering which fuel is best.

Most people will employ some sort of a calculation to divide up the additional cost of purchasing and servicing a diesel over time, compared to that of a petrol. This can be helped along if you also consider the average running cost of a petrol equivalent. Comparing these costs together over the time you expect to own the vehicle will reveal which fuel and engine you are going to require if it simply comes down to a decision based on costs.

For a pickup truck then the greatest factor is possibly going to be performance and diesel will provide that extra power and capability when moving large or heavy loads. If you are going to be choosing a manual gearbox, then that additional torque of the diesel is also going to reduce the friction on the clutch associated with revving higher with a petrol engine to achieve enough power to engage the transmission.

Experience will often be a good guide to choosing between these two, so you may do some surfing at some of the truck forums found around and about and see what other people have to say about their own vehicles and whether or not their experiences may be relevant to your situation.

Are you in Taiwan?

3

[quote=“sulavaca”]

Diesel certainly has benefits over petrol power, but the question is whether you will require the advantages, or suffer the drawbacks more perhaps.
Diesel generally offers more torque than petrol engines, so for pulling heavy loads, the diesel is your engine. Also because diesel engines tend to be some form of direct, or semi direct injection, less of the fuel is wasted because of inefficient induction and so you get a more complete burn, resulting in the harvesting of more power per droplet of fuel, meaning greater economy than a typical Otto cyclic petrol engine. Diesel is cheaper to produce than petrol, requiring less refining and can often be found at cheaper prices. Those are some of the advantages of diesel.

Disadvantages of diesel are numerous. Diesel tends to be the dirtier fuel, more so than petrol, but the dividing line between diesel and petrol for most people comes down to cost, more often than any other factor. The costs is often the misunderstood concept when deciding between one type of vehicle over the other. Here are some of the factors you will have to decide for yourself.
Diesel engines are often more expensive to produce than petrol engines due to the necessary precision of their components and the additional strength requirements of their internal components. This often means than diesel vehicles are a higher purchase price. Service intervals of diesel vehicles generally spaced closer together than their petrol equivalents, meaning more expensive service costs are a factor.
Diesel is a dirtier fuel and coupled with engine components under greater stress can reduce the economic life expectancy of a diesel engined vehicle. Check reliability factors of the vehicle you are considering and expected useful longevity if possible. Diesel fuel in some areas has been made artificially expensive to try and dissuade people from owning more polluting vehicles. This will perhaps change in time as vehicle design and pollutant levels improve, but in the meantime produces yet another factor when considering which fuel is best.

Most people will employ some sort of a calculation to divide up the additional cost of purchasing and servicing a diesel over time, compared to that of a petrol. This can be helped along if you also consider the average running cost of a petrol equivalent. Comparing these costs together over the time you expect to own the vehicle will reveal which fuel and engine you are going to require if it simply comes down to a decision based on costs.

For a pickup truck then the greatest factor is possibly going to be performance and diesel will provide that extra power and capability when moving large or heavy loads. If you are going to be choosing a manual gearbox, then that additional torque of the diesel is also going to reduce the friction on the clutch associated with revving higher with a petrol engine to achieve enough power to engage the transmission.

Experience will often be a good guide to choosing between these two, so you may do some surfing at some of the truck forums found around and about and see what other people have to say about their own vehicles and whether or not their experiences may be relevant to your situation.

Are you in Taiwan?[/quote]

Hi Sulavaca,

Thank you for the useful comments. I didn’t know that diesels needed more frequent servicing. What sort of servicing are we talking about? (oil changes?)

Yes, I’d definitely be getting a manual gearbox.

And yes, I’m in Taiwan.

best regards,
DB

4

What about quality of mechanics for each?

5

If I were in Europe and I would have to drive a lot, a mercedes diesel would be my preferred car, my dad puts 500,000 KM on each of his before replacing them.

Here - I thought about it, however quality of mechanics and also general maintenance of a second hand diesel would be issues I rather not deal with.

6

In Taiwan it doesn’t make sense to get a diesel unless you will drive it everyday all day long, such as delivery vehicles or buses.

7

I love Volkswagen’s turbo diesels. My dad’s got one, and he swears by them. And the 2010 lineup is gorgeous.

Their sportwagen is pretty nice, too!

8

[quote=“Dog’s_Breakfast”]
Hi Sulavaca,

Thank you for the useful comments. I didn’t know that diesels needed more frequent servicing. What sort of servicing are we talking about? (oil changes?)

Yes, I’d definitely be getting a manual gearbox.

And yes, I’m in Taiwan.

best regards,
DB[/quote]

Yes, indeed the greatest attention is on the engine and fuel line with a diesel. They require more maintenance than a petrol in general. I asked if you were in Taiwan as there are some different factors here. One is the average mileage, which is around only 10,000km per year on most vehicles. If you follow this very low mileage trend then there is probably going to be no cost effectiveness in a diesel, in fact one may even be more expensive. The fuel is not heavily taxed on diesel however, so that could be a very slight saver. If you are in Taiwan and not in the mountains, then the chances are that you will be travelling mostly flat roads, so I am not sure if the extra torque of a diesel will be necessary for you. Of course if you do happen to live somewhere with hills, then that power may come in handy.

As someone mentioned and what I was hinting at with servicing costs, diesels can be tricky to maintain, especially as they get older. If its an older vehicle you are looking at, then either make sure you have a trusted diesel mechanic, or perhaps stick with the petrol.

9

[quote=“sulavaca”][quote=“Dog’s_Breakfast”]
Hi Sulavaca,

Thank you for the useful comments. I didn’t know that diesels needed more frequent servicing. What sort of servicing are we talking about? (oil changes?)

Yes, I’d definitely be getting a manual gearbox.

And yes, I’m in Taiwan.

best regards,
DB[/quote]

Yes, indeed the greatest attention is on the engine and fuel line with a diesel. They require more maintenance than a petrol in general. I asked if you were in Taiwan as there are some different factors here. One is the average mileage, which is around only 10,000km per year on most vehicles. If you follow this very low mileage trend then there is probably going to be no cost effectiveness in a diesel, in fact one may even be more expensive. The fuel is not heavily taxed on diesel however, so that could be a very slight saver. If you are in Taiwan and not in the mountains, then the chances are that you will be travelling mostly flat roads, so I am not sure if the extra torque of a diesel will be necessary for you. Of course if you do happen to live somewhere with hills, then that power may come in handy.

As someone mentioned and what I was hinting at with servicing costs, diesels can be tricky to maintain, especially as they get older. If its an older vehicle you are looking at, then either make sure you have a trusted diesel mechanic, or perhaps stick with the petrol.[/quote]

OTOH its my strong impression, (from mostly anecdotal evidence, and certainly not an expert opinion) that newer diesels (at least in cars) with direct injection, high pressure common rail fuel systems, are significantly more fragile than the older indirect injection designs. I also suspect that in order to lighten the engines and make them more “civilised” they’ve been weakened. I’ve heard of lots of cracked heads in Citroens and Peugeots, which had the rep of making diesels acceptable to the average car driver.

This would be especially true if you were at all serious about your oil palm fuel source, mentioned in another post. If you go for a full biodiesel conversion (a non-trivial bucket chemistry task) there should not be any issues, but there are significant risks if you use straight unconverted vegetable oil, which is otherwise much easier and cheaper. While it may be OK/worth it with an older normally aspirated indirect injection design (Delica, Econovan) it would IMHO be far too risky with a new vehicle with an unsuitable direct injection engine. Turbos are definately out, (again IMHO.)

10

A Perkins 4-108/107. Great engines. Even a hamfisted know like me can fix almost any part. Even the French can build ones that go 200k miles.

11

I only know of that as a boat engine. I guess it probably does manifest itself in trucks, but probably not in Taiwan.

I had a Perkins Prima (based on the Leyland “O” series but with Perkins diesel bits) direct injection engine in a Maestro which seemed to be ridiculously economical but I had to leave it on my brothers farm when I came to Taiwan. Think he’s scrapped it. Pity.

Oh, almost forgot…Ha harr!

12

I only know it as a boat engine too. I was told it was a marinized truck engine.

13

Forgot I had a Perkins 4ish litre engine in a Dodge 50 (truck) until it (the truck) got nicked. Nice truck, that’ll teach me not to park up in Kings Cross. That engine might have been a pretty close relative but 4L seems a bit big for a sailing auxilliary (?) Perkins phylogeny is complicated, so I dunno. It just ran so I never really learned much about it, and there were no manuals on’t web in those dark days.

Wickipedia says ED 4.108 (presumably the same as the marine engine) was used extensively in vans and cars, Ford Transit, Opel Blitz, Alfa Romeo Giulia, Alfa Romeo Giulietta.

However, all this Perkinology has nothing to do with the OP, so I’ll shut up about it.

14

Diesels are great.
The maintinence is not more or less than a gasoline, but parts tend to be a litle more expensive and bad fuel filters cause more problems than if on a gasoline.

I have been working on diesels from 40hp and up to 4500hp. Nothing to fear.

15

Did anyone mention the new and clogged particle emissions filters on many of them?

16

It’s just crap. Get it off.
When I grew up I had to breath exhaust from leded fuel and I’m still alive.
And here in Taiwan geting cancer from diesel smoke particles is a minor danger compared to being killed on a schooter.

17

It’s just crap. Get it off.
When I grew up I had to breath exhaust from leded fuel and I’m still alive.[/quote]

Yes, but you have somehow since morphed into a fish and I am not sure that, that is altogether a good thing.

18

It’s just crap. Get it off.
When I grew up I had to breath exhaust from leded fuel and I’m still alive.[/quote]

Yes, but you have somehow since morphed into a fish and I am not sure that, that is altogether a good thing.[/quote]

Absolute minimum credible prediction is a 2m sea level rise. We should all make like fishes

19

Not to take away from what you said edithglow, but another absolute minimum credible prediction is that human kind will one day become extinct.

Now how do I link that with diesels to stay on topic?

20

I think the baddies in Water World should have used diesel power as opposed to 2-stroke rotax engines. Which would have been more tolerant of water contamination?

Hey Ducked, you now owe use premium handcart pic’s and an update on your escape from Alcatraz plan.