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Discussion Starter · #1 ·
1) What disorder is generated within a motor when this is shaking?

2) What kind of engines have a greater compression and why? (gasoline engines)

3) What's the main difference between a diesel engine and a gasoline engine?

4) What means and what's the use of KOEO and KOEF?

5) What is the meaning of MAF, DOHC, ABS, V-TEC?


If I didn't translate them correctly here is the original questtionaire:


1) Qué desorden se genera dentro de un motor cuando este cascabelea?
2) Qué tipo de motores tienen mayor compresión y porqué? (motores a gasolina)
3) Cual es la principal diferencia entre un motor de gasolina y uno de diesel?
4) Qué significa y para que se utiliza el KOEO y KOEF?
5) Qué significan las siglas MAF, DOHC, ABS y V-TEC?


I hope you can help me guys! :D
 

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1. don't know what it's asking?

2. engines with a smaller combustion chamber and larger displacment have a higher compresion. High performance engines usually have higher compression.

3.See below.

4. No clue.

5. MAF=mass air flow, DOHC=dual overhead cam, ABS=anti-lock brake system, V-TEC=Valve timing electronic control.

Where are you getting this?

[Fixed numbers]
 

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3.) Diesel vs. Gas

Diesel engine uses Glow plugs, runs at lower RPMS, less refined fuel
Gas engine uses Spark plugs, higher RPMS, more refined fuel

I would guess the glow plugs vs. spark plugs. Spark causes combustion, glow plugs heat during compression, till combusts.
 

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3) Diesel vs. gas

Diesels ignite their fuel by compressing the air fuel mixture so much that the heat from compression ignites the fuel. Gas engines compress their mixture about 1/2 to 1/3 as much as a diesel, and use a spark plug to ignite the mixture.

Diesel fuel has a much higher flash point, which allows the higher compression ratios. Gasoline will ignite much easier. The higher the compression ratio, the more efficient the combustion is, contributing to better fuel economy.

Diesel fuel contains more energy than gasoline, gallon for gallon. This contributes to better fuel economy than a gasoline engine.

Diesels can operate in a very wide range of air-to-fuel ratios, and have no throttle plate. Gasoline engines must stay within a fairly small range of air-to-fuel ratios, and require air entering the engine to be restricted when less fuel is being burned. Diesels have no throttle plate restriction that the engine must work to overcome, so this also contributes to their efficiency.

Diesel fuel burns more slowly than gasoline, so it's not suited to high rpm operations.
 

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1. I don't understand this question.

2. Generally speaking you increase the compression on a gasoline engine to increase power/efficiency. The downside to this is that you need higher octane gas with the higher compressions to prevent preignition. Manufacturers might increase the compression ratio if they were looking to generate more power from a motor.

3. Diesels are compression ignition. The air/fuel mixture is compressed until it spontaneously ignites. This is why they have such high compression ratios (14:1 - 20:1). Glow plugs are only there to assist in starting, particularily in cold weather. Once the engine is running, glow plugs are not needed. Gasoline engines require a spark to ignite the air fuel mixture.

MelvinJ - how do diesels control rpm without a throttle plate? I was under the impression diesels also control rpm by regulating the amount of air entering the engine by use of a throttle plate.

4. I've never heard of these terms.

5. T-Keith gave these answers.
 

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I assume that KOEO and KOEF translate differently into English. The two terms (as I see them) are for diagnostic procedures. "Key-On, Engine-Off" and "Key-On, Engine-On" (or Engine-Running) are usually used to pull codes from engine's computer.

By the way, "VTEC" is a Honda term only...it refers to Honda's specific variable timing system.
 

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Originally posted by T-Type@Jun 16 2004, 02:15 PM
MelvinJ - how do diesels control rpm without a throttle plate? I was under the impression diesels also control rpm by regulating the amount of air entering the engine by use of a throttle plate.

My understanding is that RPM is controlled just by the amount of fuel injected. The more fuel injected and burned, the greater the power/engine speed.

Does this jibe with anybody else out there?
 

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Discussion Starter · #8 ·
OK. let me see if I can make easier to understand the first question...

1) What problem is caused in an engine when this is acting recklessly?
 

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Originally posted by gerardo_zg@Jun 16 2004, 12:17 PM
OK. let me see if I can make easier to understand the first question...

1) What problem is caused in an engine when this is acting recklessly?
Many things can cause that, but timing could be one of the main reasons
 
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