And why are they capable of massive mileages?

cut and paste from a google...

 

MYTH: Diesel engines run for thousands of hours before requiring major maintenance. Diesel engines gained the reputation for longevity based on their use in continuous operation such as trucking, generators and commercial vessels. Diesel in trucks and commercial vessels can run for thousands of hours because they often are run continuously without ever being shut down, or shut down only infrequently. Without going into a technical explanation, this is what accounts for long life in commercial applications. That does not mean, however, that they last longer in terms of the calendar: commercial engines run for vastly more hours, but have to be rebuilt just as frequently by the rising and setting of the sun.

i would agree tbh, any engine thats is good from the factory, petrol or diesel, should last a very long time if it is maintained as it should be :)

 

as for the smoke thing, i think its just the nature of the gases that are burnt?

isnt it something due to the glow plugs getting old, plus filters getting blocked etc.

isnt it something due to the glow plugs getting old, plus filters getting blocked etc.

 

I thought glow plugs were just for starting the engine, and filters were on the wrong side of the engine (induction not exhaust)....

 

Just wondering why what ever it was - why we don't have the same longjevity in petrol engines...

 

I would have thought high performance engines like ours which are made with fine tolerances would in theory last much longer than slapped together mass produced diesels - but there not.

 

So what is it that makes diesels so good? I don't buy that myth thing.....

I thought glow plugs were just for starting the engine, and filters were on the wrong side of the engine (induction not exhaust)....

 

I would have thought high performance engines like ours which are made with fine tolerances would in theory last much longer than slapped together mass produced diesels - but there not.

 

glow plugs are like spark plugs, they take a while to warm up from cold though, thus the glow plug light on diesels!

 

i see where your coming from on the second part but in another sense they are more highly strung engines and generally get driven with a drive it like you stole it type manner!

Diesel fuel is a better lubricant than petrol so is less harmful to the oil film on piston rings and cylinder bores. Plus having no electrical ignition system greatly improves the reliability due to less-violent changes in pressure than in a spark-ignition engine. Also diesel engines are built more robust to be able to withstand the higher compression ratio they need as its the heat from compression that ignites the fuel and Diesels are usually a lot slower reving. Smoking in older Diesels is usually due to a air to fuel ratio imbalance, either the fuel system is delivering too much fuel into the engine or there is not enough clean air which could be from carbon build up in the intake, faulty injectors or injector pump. Simple as that :)

Diesel fuel is a better lubricant than petrol so is less harmful to the oil film on piston rings and cylinder bores. Plus having no electrical ignition system greatly improves the reliability due to less-violent changes in pressure than in a spark-ignition engine. Also diesel engines are built more robust to be able to withstand the higher compression ratio they need as its the heat from compression that ignites the fuel and Diesels are usually a lot slower reving. Smoking in older Diesels is usually due to a air to fuel ratio imbalance, either the fuel system is delivering too much fuel into the engine or there is not enough clean air which could be from carbon build up in the intake, faulty injectors or injector pump. Simple as that :)

 

problem solved? questions answered?

Certainly they have improved in the last 25 years. hen I was an apprntice on the truck line at Bedford trucks the engines were not the best fit. If we had to many pieces of a certain size, ie the bore in the block was to big, then they would be driven round the car park for a while on a pallet to cool them down and change the sizes by a few thow.

 

Darrell

problem solved? questions answered?

 

Thats something from my miss spent apprentiship on coaches then lol apart from i used to come home smelling like a diesel pump :smash:

Thats something from my miss spent apprentiship on coaches then lol apart from i used to come home smelling like a diesel pump :smash:

 

lol i know that feeling, made the mistake of volunteering for an aircraft fuel tank entry course when i was working at bournemouth, guess who got the jobs in the tanks after that! kerosene is very much like diesel :)

lol i know that feeling, made the mistake of volunteering for an aircraft fuel tank entry course when i was working at bournemouth, guess who got the jobs in the tanks after that! kerosene is very much like diesel :)

 

yep lol as i was the apprentice or the little shit as i was known i was the one who had to climb up on top of the diesel tank when the tanker came in to fill it up and tell him when to stop. The hole i had to look through with my lead light was about 2 inches in diameter. On this occasion i was up on the tank waiting to hear the noise of the air coming out so knew when to tell him to stop pumping, i heard the noise "ok stop" the noise got louder, still pumping "OK stop" the noise got even louder "STOP" WOOSH to late the fooking lot sprayed out the hole like a fountain all over me fooking soaked bulb on the lead light smoking so threw that, got down and they are all on the floor pissing themselves, coont had gone a piss. Got covered in spots from it after that :rofl: :rofl:

 

Isnt Kerosene just a Diesel and Parafine mixture?

Diesels have a higher cylinder compression and built stronger due to this, you can also run nos on a diesel with much less risk of damage. They have a higher compression as diesel requires this to quickly combust. Diesel is not explosive like petrol gas so the very hot glow plug is required not just a quick spark.

Diesels have a higher cylinder compression and built stronger due to this, you can also run nos on a diesel with much less risk of damage. They have a higher compression as diesel requires this to quickly combust. Diesel is not explosive like petrol gas so the very hot glow plug is required not just a quick spark.

 

Only uses the glow plug to heat the combustion chamber up when the engine is cold, after that they are not needed as the high compression heats the cylinder up and the fuel mixture is sprayed in at such a high pressure its like a fine mist which ignites from the heat produced by compression. Larger Diesel engines like Trucks etc dont need glow plugs to start a cold engine as the cylinder capacity is that much larger it produces enough heat to combust with out the glow plugs

Only uses the glow plug to heat the combustion chamber up when the engine is cold, after that they are not needed as the high compression heats the cylinder up and the fuel mixture is sprayed in at such a high pressure its like a fine mist which ignites from the heat produced by compression. Larger Diesel engines like Trucks etc dont need glow plugs to start a cold engine as the cylinder capacity is that much larger it produces enough heat to combust with out the glow plugs

 

didnt realise that! something new everyday :)

How many new diesel cars have u been behind that are smokey when they are kicked, quite a few of them i'd say. I have seen commercials going 2 million kilometers without any major surgery all down to the servicing. Again modern engine managements can have a lot to do with smoke reduction but the thing I can get is why the newer cars/trucks actually burn more diesel and dont give as good a mpg figure as they could all down to emissions. ie on some older trucks the engine ecu can be reprogrammed from Euro 1 software to Euro 2 software but it costs the owner 1 mile per gallon all for cheaper tax.

 

I have seen plenty modern diesel cars that are smokey but not like thick black unburnt diesel fumes but just a bit reeky when they are kicked.

 

Cheers John Crisp

How many new diesel cars have u been behind that are smokey when they are kicked, quite a few of them i'd say

 

That's just because of poor fueling, get it fixed up by someone like Van Aaken and most of that goes away.

Edited my post andy as I hadnt finished warbling. I think the smoke is down to software/programming of the engine ecu with a lot of vehicles. At work we are getting 2 year old and newer buses reprogrammed because of the reek when the pull away.

depends on the smoke, little puff of black smoke when given some greif is just removal of a bit of carbon build up.

Blue smoke when started from cold is normally worn injectors providing the wrong fuel/air mixture.... When i was at school one firm that ran the school bus service used from 25 y/o + scrap heaps. Hole place would be covered in a blue haze for 5 minutes after they were started.

 

Diesel technology has evolved amamzingly in the last few years, had a go in an 07 reg BMW 320d the other day, not far of performance wise from my 1998 323i I had. Quite amazing.

Petrols are beginnging to follow suit, BMW has just started fitting Direction injection systems (and turbos) to some of its petrol line up. The difference in economy and performance is staggering.

Current 530i manages an output of 272BHP a 0-60 time of 6.5 seconds whilst returning an average of 37.7 mpg. (those figures are for the automatic version!)

There is no such thing as a Deisel engine

There is no such thing as a Deisel engine

 

not spelt like that there aint, no :rofl:

not spelt like that there aint, no :rofl:

 

Come on then you are the only one that gave an answer based on fact and not what you had heard.

 

Why are they not Diesel engines?

Come on then you are the only one that gave an answer based on fact and not what you had heard.

 

Why are they not Diesel engines?

they are internal combustion engines. And only called that after the man who invented this type of engine

they are internal combustion engines. And only called that after the man who invented this type of engine

 

Close

Close

 

or do you mean the diesel engine works by injecting fuel into the air that is already heated up in the combustion chamber, as opposed to the petrol engine which uses the Otto cycle which mixes fuel and air together before it enters the combustion chamber

You was right about Diesel, he got the idea from an exibit in a museum he saw when he was 12 years old.

 

They are called compression ignition engines due to the fact, as you rightly said, its the heat of the air compressed by the piston that ignites the fuel, this can be almost any combustable liquid and some manufactureres still call them heavy oil engines.

 

Petrols are spark ignition engines.