Hot answers tagged

57 votes
Accepted

Why do heavy vehicles almost always use diesel engines?

Torque is the name of the game. High torque is needed to move heavy loads. If comparing a gasoline engine to a comparable diesel engine the diesel will always have higher torque. The higher torque ...
vini_i's user avatar
  • 16k
29 votes

Why do heavy vehicles almost always use diesel engines?

A major, but often overlooked, reason for the dominance of gasoline engines in passenger vehicles is the need for diesel engines in heavy vehicles. A given quantity of crude oil, depending on its ...
dotancohen's user avatar
  • 1,733
29 votes

Small amount of wrong fuel type put in the tank

The main concern with using petrol in diesel systems is that diesel is used to lubricate the fuel pump, which petrol cannot perform adequately, which will shorten the useful life of the fuel system. ...
Zaid's user avatar
  • 39.2k
29 votes

What happened to my car?

Being a diesel and that the engine ran for a minute with the ignition turned off, makes it highly likely that you experienced diesel runaway. During normal operation, diesel is used as fuel for the ...
HandyHowie's user avatar
  • 25.2k
22 votes

Why do heavy vehicles almost always use diesel engines?

To OP’s main question: “Why do heavy vehicles almost always use diesel engines?” Answer: Cost and dependability. Diesel engines are significantly more expensive, but have lifetimes many times greater ...
robertb556's user avatar
16 votes
Accepted

Diesel Engine Runaway - What is it?

Since the diesel has no physical throttle, power is controlled by limiting fuel. Air is always available so any unintended, un-metered fuel will cause the engine to increase rpm and power output. The ...
Fred Wilson's user avatar
  • 11.6k
16 votes
Accepted

Small amount of wrong fuel type put in the tank

The main problems from misfueling a diesel car with petrol stem from the fact that (as Zaid points out) petrol doesn't provide the lubrication effect of diesel fuel and as a solvent it can actually ...
motosubatsu's user avatar
13 votes
Accepted

Two-Stroke Diesel Engine - Do they use forced induction on them?

The only two stroke diesel i'm aware of is the Detroit diesel. The Detroit diesel does use forced induction but not in the way that you think. From your description it sounds like your describing a ...
vini_i's user avatar
  • 16k
13 votes
Accepted

Is it possible for a diesel engine computer to detect (and prevent) a runaway condition?

The common way that effective overspeed protection is provided on diesels in the oil and gas industry is way more simple than using electronics to effect a shut down. The only effective and reliable ...
Jimmy Fix-it's user avatar
13 votes
Accepted

Is it safe to transport diesel fuel in a plastic can inside of a plastic tub? Or store it in the same way?

Fuel cans contains carbon in the plastic. This is a large part of why traditional fuel canisters are black. This dissipates static charges by bringing the plastic from perfect insulator to the megaohm ...
vidarlo's user avatar
  • 702
12 votes

What's the cause of Diesels' typical clatter noise?

Two types of sounds There are two sound types that emerge from a diesel engine. Combustion Noise Mechanical Noise Combustion noise is created by the compression ignition process which compresses ...
DucatiKiller's user avatar
  • 32.9k
12 votes
Accepted

How did they start diesel engines before the glow plug was invented?

Glow plug is merely an aid for starting the engine. There are many designs still produced today without any glow plugs (eg military diesels run without any electricity), and even many modern diesel ...
Agent_L's user avatar
  • 815
12 votes

ATF in engine oops

I would run the engine again for a few minutes and then drain that engine oil as it will have any ATF that was still in the galleries. Then fit a new filter and refill with fresh oil. After that you ...
Solar Mike's user avatar
  • 34.7k
12 votes
Accepted

Scraping sound in new small engine

I actually decided to go ahead and just tear into it no matter the answer and can make the following statements: Bore and piston rings were absolutely immaculate and there was no scraping whatsoever ...
Yanick Salzmann's user avatar
11 votes

Why do heavy vehicles almost always use diesel engines?

Given two engines of similar weight, both operated at their respective optimum efficiency (i.e. maximum mechanical work done per unit of chemical enthalpy in the burnt fuel), you will end up with ...
user13882's user avatar
  • 111
11 votes
Accepted

How are diesel engines better for the environment than gasoline?

They aren't better for the environment But efficiency is often confused with emissions. The average person would think that because diesel engines are more efficient and burn less fuel, they must be ...
Zaid's user avatar
  • 39.2k
11 votes

Small amount of wrong fuel type put in the tank

This will not be a problem - in fact, some of the older truckers used to add 2% of petrol to the diesel to help in winter conditions to help reduce waxing of the diesel fuel.
Solar Mike's user avatar
  • 34.7k
11 votes

VW Polo Engine Oil Light Blinking on hill

I have a VW TDI diesel, but an earlier model. Your oil light comes on when there is a gradient but not because of a gradient. A mechanic who blames the tilt of the ground for the light on the dash ...
MTA's user avatar
  • 5,935
10 votes
Accepted

Why don't all diesel engines have throttle plates?

tl dr: By adding a throttle plate, it creates the vacuum needed to draw in gasses from an EGR valve. Since diesel engines are designed to run lean, they don't need throttle plates to run. They ...
Pᴀᴜʟsᴛᴇʀ2's user avatar
10 votes
Accepted

What would cause a short to ground while driving - how to locate the problem?

The most likely cause is that the cable that runs down to the starter motor has been rubbing against the body or the engine and has worn through the insulation.
HandyHowie's user avatar
  • 25.2k
9 votes
Accepted

What's the cause of Diesels' typical clatter noise?

The engine operates on high compression to ignite the fuel at very low RPMs which gives it it's distinctive sound. The lower RPM makes the ignition of each cylinder easier to hear and the compression ...
JaredW82's user avatar
  • 256
9 votes
Accepted

Diesel engine timing?

Diesel engine timing is accomplished through the fuel injectors (they inject fuel at the proper times). Proper timing prevents pre-ignition because there's no fuel in the cylinder yet to ignite. Glow ...
Jason C's user avatar
  • 4,900
9 votes

Why does "i" stand for petrol?

It stands for Injection as in Fuel Injection.
method's user avatar
  • 2,760
9 votes
Accepted

Why does "i" stand for petrol?

The i is a leftover from the 1970s, when a few companies (BMW and Mercedes, notably) started replacing the carburetor on their petrol engines with fuel injection. The marketing department saw an ...
Hobbes's user avatar
  • 4,422
8 votes
Accepted

Ford Focus engine cuts out at 3000+ RPM

In this case replacing the fuel filter for new seems to have done the trick. I was able to find one for roughly £27 on eBay and fitted it myself in under 45 minutes. Thought I'd leave the information ...
Equalsk's user avatar
  • 381
8 votes
Accepted

Can diesel engine be harmed as easily as gasoline engine by over-revving?

The rev limit of a petrol (gasoline) engine is generally set to protect the internals of the engine. Less sporty engines are designed to a cost and their components may not have the strength or ...
Sam's user avatar
  • 1,708
8 votes

2004 powerstroke white smoke now no start

I'm not a diesel mechanic but after a quick search the number one cause of no starts on the 6.0 is lack of oil pressure. The injectors need 500psi minimum to operate. This indicates there is not ...
Ben's user avatar
  • 10.7k
8 votes

Does free revving a diesel engine to 4000 rpm (1.6 crdi- hyundai) cause any damage?

Short answer - no. It's perfectly okay. And , it's also perfectly okay to be annoyed. It's one of those things mechanics like to do (no offence to anyone). Similar to endlessly hitting refresh on a ...
chilljeet's user avatar
  • 2,196
8 votes

What preparations to make before changing oil on old neglected tractor diesel engine

The engine in your tractor should hold are 6.5 quarts (6.2L) of 15W-40 oil. That amount should fit in most oil collection pans. If you want to use kitty litter as oil clean up, that's a great idea. I'...
Pᴀᴜʟsᴛᴇʀ2's user avatar
7 votes

Diesel Engine Runaway - What is it?

If you didn't realize, diesel engines do not have throttle plates (butterflies) like gasoline engines which controls the amount of air going into the system. The way it is controlled is through the ...
Pᴀᴜʟsᴛᴇʀ2's user avatar

Only top scored, non community-wiki answers of a minimum length are eligible