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Was asked by my boss today to get his van started. He said when he went to it last night it wouldn't fire so today it had to go to the garage so had to run.
I asked him why the silly plastic engine cover was broken in two , "Oh i was looking for the spark plugs and leads to check them" he replies.

I spend the next 5 minutes creased up on the floor with laughter, then have to explain how a diesel engine works


(it was the heater plugs - a squirt of something highly flamable down the air intake got it going)
 

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Engineers Do It Better.
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Lol, ill let you in on a secret - I didn't know anything about CI engines until I did a lab on them at Uni 2 years ago :$ I was 21 LOL the shame...
 

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finds titles too "mainstream"
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One does not need to know how to paint to appreciate a painting, nor how to play a guitar to appreciate music.

Why should he know anything about a diesel engine to appreciate cars.

To be honest I know bugger all about diesel engines despite owning one for 2.5yrs because frankly as long as it worked I didn't give a toss, I think I only opened the bonnet on that car 3 times and one of those was at the dealership, and the other was changing a light blown headlight. Mind you I did hate that car... It's a different story with the MX obviously
 

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Dr. Eunos
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I must admit to being highly sceptical when an instructor informed us that a Diesel engine does not even have a throttle butterfly (how mad is that???) , when I was an apprentice aero engine technician many moons ago.
 

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Tea of the Sea
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I'm with ISO on this... why post this up on a forum?

HURR DURR YOUR BOSS IS STUPID, etc.

who cares? just because you "know the basics" doesnt mean everyone should. Do you know the 'basics' of how everything you use in daily life works? probably not.

You should probably have explained it to him properly instead of taking the piss out of him.
 

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Nah to be fair, i Lol'd when my mate did the same when he got his civic type-s

I said, you probably need new spark plugs and HT leads if it's not running quite right....(he went down to halfords...and he was very angry at me afterwards)

That said there is a lot of misconceptions about diesels...I was told that diesels have no butterfly valves, and simply change poweroutput by fuel added..I was also genuinely amazed to discover that this is total bollocks on modern diesels...

That said, include a mechanical fuel pump..and turbo runaway can be quite scary...
 

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Supreme Overlord of nutzF1
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My boss is the wrong side of 40 and a big Topgear/F1 fan and goes to all the major car shows (Goodwood/NEC) really thought he would know better !
I'm the wrong side of thirty, watch Top Gear and F1, go to car shows and motor races and know the basics of how a petrol engine works. I have no idea how a diesel engine differs from a petrol one. I learned about thirty seconds ago that they don't have spark plugs so the difference is probably greater than I imagined. Maybe one day if I'm really bored I'll look it up on the internet but there are probably six thousand things I'd rather look at first (and that's grouping all types of porn into one thing).
 

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My boss is the wrong side of 40 and a big Topgear/F1 fan and goes to all the major car shows (Goodwood/NEC) really thought he would know better !
I'm the wrong side of thirty, watch Top Gear and F1, go to car shows and motor races and know the basics of how a petrol engine works. I have no idea how a diesel engine differs from a petrol one. I learned about thirty seconds ago that they don't have spark plugs so the difference is probably greater than I imagined. Maybe one day if I'm really bored I'll look it up on the internet but there are probably six thousand things I'd rather look at first (and that's grouping all types of porn into one thing).
[/quote]

The basics are that it uses compression to ignite the fuel mix rather than a spark. To get this ignition they need to have very high compression ratios, this is where most of their efficiency comes from. To get the very high compression ratio they need to be built very strongly, which is why they're dead heavy.

The lack of a spark to ignite the fuel explains why they die above 4k, (Fuel generally takes about the same amount of time to burn, but as revs increase the time available decreases so you ignite it earlier). You want peak pressure to occur at more or less TDC. With a diesel that's the only time you can ignite the fuel, so as revs increase more and more of the 'bang' is wasted out of the exhaust valves rather than being used to push the piston down.

Though to confuse matters there are spark ignition diesel engines too...
 

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Oh, hai!
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Do you know the 'basics' of how everything you use in daily life works?
Yes. At a basic level, it's almost intuitive. But that's just how my mind works, I like to know how shit functions and can imagine how it would go about its job.

The difference between how a diesel and petrol functions I learnt many years ago. Wikihopping related articles is a great way to learn stuff.
 

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Diesel is easy enough. They run to much compression, so it just goes boom before the spark has a chance to light it. Which is good, as there is no spark.
The fact they go boom means they have to be tougher. This means keeping the mixture correct has no consequence, so you can regulate the fuel delivery and ignore the air volume.

Thats quite condensed, but as a car lover you don't need to know about diesels anyway.

Edit: Looks like I hit 'Post' a bit late. Like an hour lol
 

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Dr. Eunos
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Oh dear, still a few misconceptions regarding Diesel engines on here, they do not have throttle butterflies....
I had a `runaway Diesel` once, it was a firms` car a 1990 Audi 80 Turbo D and I had managed to `adjust` the locking collar on the governor screw to pep it up a bit - took it up a big hill near home and once I hit full boost (had shortened the wastegate actuator rod too...) it was awesome, black smoke like a racing truck and about 50% extra power, trouble was when I came off the throttle at the top of the hill, it stayed on full power, luckily I knocked it off on the key (which just closes a fuel solenoid cut-off on the Bosch pump) and managed to stop the car, pretty scary!
Another time in an almost new 1994 Audi 80TDI while overtaking an articulated truck, the `revolutionary` drive by wire throttle/fuel pump control suddenly decided it wanted to be on tick-over instead of full poke leaving me out in the middle of the road alongside the truck - that was very un-funny...
Another seriously dangerous Diesel moment happened to me in a new Vauxhall Frontera 2.3TurboD, I had been flat out on a motorway (about 85mph..) came off at a junction and the throttle pedal stayed stuck to the floor FUCK!!!, knocked the key off, sorted out a shorter braking zone than I had originally planned for and parked it on the grass at the side of the roundabout, popped the bonnet to see what had caused the issue, only to find a Allen-headed through-bolt about 5" long had un-screwed itself out of the pump and had jammed the throttle quadrant in the wide-open position, nice....I drove the heap back to the dealer we bought it from (using only the key to modulate the power) threw the key back at the sales manager and `rejected the vehicle` got all our money back and bought another Audi instead.
 

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Dr. Eunos
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Can only presume Alfa fit one because they don't trust their own electrics enough to stop a Diesel engine? Will have a look at one next time I am near a scrapyard
 
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