Questions tagged [engine]
Internal Combustion Engine. Most engines in road going vehicles are 4-cycle internal combustion gasoline engines.
221
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9answers
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What actually happens when there is not enough oil in a car engine?
When a car is topped up with oil, it clear to most people that you are supposed to fill it to the recommended amount as specified by the manufacturer (normally on a dip stick).
What exactly are all ...
26
votes
4answers
498k views
What actually happens when there is way too much oil in a car engine?
I saw the answers to a question I posted recently highlighting the disadvantages of having too little oil in an engine, but that got me wondering what if the complete opposite were to occur!
I know ...
19
votes
3answers
55k views
Lugging the Engine (Manual Transmission)
So...lugging the engine obviously isn't something that is good. But why?
For example when you feather a clutch to get the car moving, it lugs for a quick moment when you hit the catch point (When ...
9
votes
3answers
226k views
Oil in coolant - how much trouble am I in?
I have oil in my coolant reservoir. Could it just be the head gasket or is it almost certainly the entire engine or might it be something else entirely?
Thanks in advance...
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votes
1answer
5k views
What is a stress riser?
What is a stress riser and why is it important to avoid them during engine construction or rebuild?
18
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2answers
5k views
What is a leak down tester and what can I do with it?
Background
There are quite a few head gasket related questions on the site. Coolant or water in the oil, oil in the coolant or water in a radiator, etc. I'm thinking that some instruction on howto ...
18
votes
6answers
116k views
Engine power specification at different rpm?
Car companies advertise the power of an engine at different rpms.
Car 1: 80 PS at 6000 rpm
Car 2: 85 PS at 6500 rpm
What does the power at different rpm mean?
Does it mean Car 1 has better power ...
38
votes
3answers
370k views
What does a water-like drip coming out of the exhaust of the car signify?
Sometimes while driving in the traffic, I come across a car or two which would be dripping water-like drops from its exhaust steadily in 4-5 second intervals. I tried to ask a couple of people at the ...
29
votes
3answers
13k views
Static vs. Effective compression: Why does higher effective compression not require higher octane gas?
Background
I've been trying to do a lot of research on boost lately because I'm planning on running a moderate turbo setup on my daily/light-duty-autox car in the future. I'm trying to get into the ...
11
votes
2answers
5k views
BSFC (Brake Specific Fuel Consumption) - How is this a beneficial measurement?
Brake Specific Fuel Consumption or BSFC
Measuring various attributes of an ICE (Internal Combustion Engine) and how it performs certainly gives a greater understanding of how a particular ICE ...
30
votes
3answers
391k views
what is difference between DOHC and SOHC?
I want to know the SOHC and DOHC configurations. On what factors an engine manufacturer decides to go with SOHC or with DOHC, what should I choose? DOHC or SOHC?
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6answers
1k views
Second hand car - Engine/Tyres/Etc
I am looking into buying a second hand car from a reputable Mercedes-Benz dealer (not just some dodgy salesman by the side of a road lol....).
Anyway, there are a few maintenance/mechanical things ...
38
votes
10answers
67k views
Is it necessary to 'burn in' or 'break in' a new car?
I've just bought a new 2011 plate car. I've heard stories of people 'burning in' engines for the first few hundred or couple thousand miles using methods such as:
Not driving above 50 mph.
Varying ...
26
votes
6answers
42k views
Is Start & Stop technology good or bad for my car? (Alfa MiTO)
I was recently in the lucky position to obtain an (almost brand new) Alfa Romeo MiTo, Progression. Like many new cars coming out these days, it has "Start & Stop" technology that turns the engine ...
20
votes
3answers
115k views
What does a flywheel do and what is it connected to?
I understand roughly how an engine works and that there is a crankshaft which is able to turn the flywheel using internal combustion.
I have just realised that I have got absolutely no idea how the ...
9
votes
5answers
3k views
What can cause a gasoline engine to suddenly & mysteriously stop (non-catastrophically)
I was thinking about this question and found myself wondering what could cause a gasoline engine to suddenly stop, and then be restartable? So not things like running out of fuel, or suffering a ...
10
votes
4answers
72k views
Is engine braking harmful? [duplicate]
Possible Duplicate:
Does Downshifting (Engine Braking) Cause Extra Wear and Tear?
My wife and I have a disagreement about a practice of mine--engine braking. When I'm driving her manual ...
9
votes
3answers
29k views
Should I avoid full throttle when driving with a cold engine?
Apparently I should avoid full throttle until my engine temperature is warmed up fully (to 90 degrees on the gauge)
Normally I just get in and drive normally after about 10 seconds, and then after ...
4
votes
2answers
4k views
Mazda 323: Plugged in Coolant Temp Sensor - Now Car won't Start
I recently bought a Manual 97 Mazda Lantis 323 1.8L DOHC 16 Valve BP.
I found the following wire unplugged on the drivers side of the engine, next to the water intake from the radiator:
It plugs ...
20
votes
4answers
206k views
What is a rod knock?
What is a rod knock? What causes a rod knock, how bad is a knocking rod, and how can I tell if a rod is knocking?
19
votes
3answers
46k views
WHY does an engine stall? (manual transmission)
Before you write off my question as one that's been answered a million times already, I want to clarify. I understand that the engine needs to go a certain rpm and when you try to engage the clutch ...
24
votes
7answers
400k views
Is idling bad for your engine?
If I sit in my car for 30-40 minutes with the AC and the car idling, does that "hurt" the engine, or does it simply waste gas and pollute the air? Would it be better if I turned off the car? A ...
23
votes
2answers
16k views
Why do we need to cool air after it leaves a turbocharger?
When we are using a turbocharger to compress the incoming air, the air gets hotter. Usually this hot air is cooled by using an intercooler before it's passed to the engine.
What is the reason behind ...
8
votes
4answers
15k views
Do fast cars need to occasionally be driven fast?
In the broad spectrum of cars, there's higher end models with sport-focused engines. Examples would be an BMW M3, and even more so Ferraris and Koenigseggs etc. Apparently they're more fussy, in that ...
24
votes
16answers
92k views
What is the purpose of plastic engine covers?
I have a 2010 Toyota Corolla. What is the purpose of the large plastic cover that stretches over my valve cover? Does it have a particular function? Are they just for looks? Or are they designed by ...
10
votes
3answers
62k views
Engine Size and Fuel Consumption
I have this weird misconception that the engine size is related to the amount of fuel being burned in one cycle(4-stroke engine). I know this is stupid but how does engine size relate to the amount of ...
2
votes
1answer
2k views
Hole-in-One. Small extension and socket fall into valve
I am very poor so I work on my house/SUV (2002 Ford Expedition) myself. Recent misfires had me changing coils and spark plugs. Well, everything is going fine until my extension comes off my socket ...
14
votes
3answers
28k views
How to begin learning engine tuning?
Quite simply, I want to begin tuning and modifying automotive engines for hobby. I have always been fascinated with cars, and I want to become knowledgeable in as many aspects of car tuning as ...
12
votes
2answers
2k views
Motorcycle Four Body Carburetor Synchronization Balancing
I would like to adjust four-body carbs by myself, in order to avoid spent money every time.
What are the basic rules, tools and secrets of synchronizing multiple carburetor bodies?
22
votes
2answers
23k views
Why doesn't the engine stall out when you come to a stop with an automatic transmission?
When you come to a stop with a manual transmission you have to push the clutch in or take it out of gear to keep the engine from stalling out. What keeps the engine from stalling in an automatic ...
10
votes
6answers
6k views
Fuel consumption at same speed of different engine
I am wondering why two car running at 100 km/h for example with a 100 hp consume less fuel that an engine of 300hp.
Even if I take a supercar lighter and more aerodynamics it will consume more.
But ...
19
votes
6answers
42k views
Is it OK to mix oil of different viscosity in a Wankel engine?
I have a Mazda RX-8 (with a Wankel rotary engine). Mazda advises North American owners to use 5W-20 oil. The engine was just replaced 200 miles ago by the dealer so it currently has 5W-20 in it.
...
9
votes
1answer
2k views
Carburettor jetting on installation of aftermarket air filter
I have a 150cc motorcycle and am planning to install an after market air filter(K&N) since the stock one was favoring fuel efficiency and not performance.
The bike has a carburetor (Mikuni) not ...
9
votes
2answers
18k views
How to test if oil is leaking into combustion chambers?
How can I test whether oil is leaking into cylinder combustion chambers and getting burnt in case of oil level loss? As opposed to, for example, leaking through the oil pan or the timing chain cover.
5
votes
4answers
62k views
Gas pedal not responding
It just doesn't work, as if I weren't even pressing it and it happens regardless of the speed. I have to turn the engine off and on again and it'll work for another 3 or even up to 20 minutes ...
20
votes
4answers
100k views
Why does a Turbocharger only produce boost when the engine is under load?
Why does a turbocharged car only produce significant boost whilst the engine is under load? Is is something to do with how much exhaust is being produced or is there some kind of valve mechanism that ...
11
votes
6answers
34k views
Why does a diesel sound like that?
My car is in the shop for a repair, and they gave me a loaner. It's a Chevy Cruze Diesel. Sitting on the driveway, my wife said, "It sounds like a truck". It does. So what exactly it is about ...
9
votes
1answer
1k views
What exactly is a head gasket?
From what I have gathered, a "head gasket" is an important part of the engine on most cars, but that is about it.
What is a head gasket?
Where is a head gasket?
Why is it necessary?
5
votes
2answers
8k views
Lean Fuel Code on V10
I have 1999 V10 Ford chassis on a 2000 Coachman motorhome. Engine starts great when cold, runs great, idles great, no skipping, missing, etc. Problem is that after driving more than 30 minutes or so ...
2
votes
1answer
14k views
How can I identify which cylinder is responsible for a petrol engine misfire?
My petrol engine has developed a persistent misfire. How can I figure out which cylinder is the culprit in order to hone in on the root cause?
22
votes
7answers
76k views
Aluminium engine vs Cast Iron engine
What is the advantage that the aluminium engines provide over the cast iron engine apart from the fact of rusting and weight reduction.
Manufacturers like to boast about their all new aluminium ...
12
votes
6answers
228k views
What actually happens when there is not enough coolant in a car engine?
I know that a lack of engine oil can destroy an engine, so I was curious as to whether it is just as bad to drive a car with a very low engine coolant.
What is engine coolant?
What exactly are all ...
6
votes
2answers
78k views
Effects of driving through deep water WITHOUT hydrolocking (car still bogged down and died)
So, yesterday we had very heavy rains, and unfortunately I was driving in an unfamiliar area of town. I drove through high water, which caused my car to sputter and so I turned around. The car behaved ...
29
votes
2answers
26k views
Why do two-stroke engine exhaust pipes look so strange?
Two stroke gasoline engine exhaust pipes are shaped strange. They expand into a wide diameter and then shrink down to a very small diameter where the exhaust gasses emerge into the environment.
- ...
26
votes
6answers
240k views
What are the risks of overfilling a small engine with oil?
I recently overfilled a 4 stroke lawnmower engine with oil. It has been run for about 1.5 hours while overfilled. It smokes a lot right after being started but after 30 seconds or so the smoke clears. ...
19
votes
2answers
13k views
Why did Ducati decide to use the desmodromic valve train rather than a more tradition valve train?
Ducati's use a unique method to open and close their valves. It's called the desmodromic valve train.
The desmodromic valve system does not use springs to close the valve, it uses the cam and has a ...
19
votes
3answers
209k views
What exactly is a "burnt valve" and what causes it?
I've come across this term a couple of times in the context of diagnosing engine-related issues, but don't know what it refers to. Here is an example from an automotive forum I frequent:
I gotta ...
17
votes
2answers
6k views
Diesel Engine Runaway - What is it?
I was watching some youtube videos and diesel engine runaway videos started to pop up where apparently the diesel engine runs out of control until it destroys itself.
My Question
What is diesel ...
13
votes
2answers
49k views
How much power (HP) do the components on the engine belt generally use?
In general, how much power (HP) to the components on the the engine belt actually use? I'm trying to come up with an estimate of how much horsepower an engine wastes on things like the AC compressor, ...
10
votes
1answer
1k views
Coolant Reservoir
Two questions,
One, is there any reason why some coolant bottles are shaped in this way?
Two, if this coolant bottle was placed on its side such as in the image below for example would coolant ...
