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How Car Engine Works II


Engine Problems
(Source: http://www.howstuffworks.com)

So you go out one morning and your engine will turn over but it won't start... What could be wrong? Now that you know how an engine works, you can understand the basic things that can keep an engine from running. Three fundamental things can happen: a bad fuel mix, lack of compression or lack of spark. Beyond that, thousands of minor things can create problems, but these are the "big three." Based on the simple engine we have been discussing, here is a quick rundown on how these problems affect your engine:
Bad fuel mix - A bad fuel mix can occur in several ways:
  • You are out of gas, so the engine is getting air but no fuel.
  • The air intake might be clogged, so there is fuel but not enough air.
  • The fuel system might be supplying too much or too little fuel to the mix, meaning that combustion does not occur properly.
  • There might be an impurity in the fuel (like water in your gas tank) that makes the fuel not burn.
Lack of compression - If the charge of air and fuel cannot be compressed properly, the combustion process will not work like it should. Lack of compression might occur for these reasons:
  • Your piston rings are worn (allowing air/fuel to leak past the piston during compression).
  • The intake or exhaust valves are not sealing properly, again allowing a leak during compression.
  • There is a hole in the cylinder.
The most common "hole" in a cylinder occurs where the top of the cylinder (holding the valves and spark plug and also known as the cylinder head) attaches to the cylinder itself. Generally, the cylinder and the cylinder head bolt together with a thin gasket pressed between them to ensure a good seal. If the gasket breaks down, small holes develop between the cylinder and the cylinder head, and these holes cause leaks.

Lack of spark - The spark might be nonexistent or weak for a number of reasons:
  • If your spark plug or the wire leading to it is worn out, the spark will be weak.
  • If the wire is cut or missing, or if the system that sends a spark down the wire is not working properly, there will be no spark.
  • If the spark occurs either too early or too late in the cycle (i.e. if the ignition timing is off), the fuel will not ignite at the right time, and this can cause all sorts of problems.
Many other things can go wrong. For example:
  • If the battery is dead, you cannot turn over the engine to start it.
  • If the bearings that allow the crankshaft to turn freely are worn out, the crankshaft cannot turn so the engine cannot run.
  • If the valves do not open and close at the right time or at all, air cannot get in and exhaust cannot get out, so the engine cannot run.
  • If someone sticks a potato up your tailpipe, exhaust cannot exit the cylinder so the engine will not run.
  • If you run out of oil, the piston cannot move up and down freely in the cylinder, and the engine will seize.
In a properly running engine, all of these factors are within tolerance.

p.s. click here to see the structure of engine in 3D-animation. Fantabulousent!



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How Car Engine Works?

Why would I like to know detail about how car engine works?
Of course, to really taste my own medicine laa.. to learn a lesson out of experience. I would focus into two topics :
1- Internal Combustion Process
2- Engine Problems
>>Thou it is a copy-paste kinda posting, but I hope it does some good to you, as how it does for me too :-)



Figure 1

Internal Combustion Process
(Resource: http://auto.howstuffworks.com)


The principle behind any reciprocating internal combustion engine: If you put a tiny amount of high-energy fuel (like gasoline) in a small, enclosed space and ignite it, an incredible amount of energy is released in the form of expanding gas. You can use that energy to propel a potato 500 feet. In this case, the energy is translated into potato motion. You can also use it for more interesting purposes. For example, if you can create a cycle that allows you to set off explosions like this hundreds of times per minute, and if you can harness that energy in a useful way, what you have is the core of a car engine!

Almost all cars currently use what is called a four-stroke combustion cycle to convert gasoline into motion. The four-stroke approach is also known as the Otto cycle, in honor of Nikolaus Otto, who invented it in 1867. The four strokes are illustrated in Figure 1. They are:
• Intake stroke
• Compression stroke
• Combustion stroke
• Exhaust stroke

You can see in the figure that a device called a piston replaces the potato in the potato cannon. The piston is connected to the crankshaft by a connecting rod. As the crankshaft revolves, it has the effect of "resetting the cannon." Here's what happens as the engine goes through its cycle:
The piston starts at the top, the intake valve opens, and the piston moves down to let the engine take in a cylinder-full of air and gasoline. This is the intake stroke. Only the tiniest drop of gasoline needs to be mixed into the air for this to work. (Part 1 of the figure)
  1. Then the piston moves back up to compress this fuel/air mixture. Compression makes the explosion more powerful. (Part 2 of the figure)
  2. When the piston reaches the top of its stroke, the spark plug emits a spark to ignite the gasoline. The gasoline charge in the cylinder explodes, driving the piston down. (Part 3 of the figure)
  3. Once the piston hits the bottom of its stroke, the exhaust valve opens and the exhaust leaves the cylinder to go out the tailpipe. (Part 4 of the figure)
Now the engine is ready for the next cycle, so it intakes another charge of air and gas.

Notice that the motion that comes out of an internal combustion engine is rotational, while the motion produced by a potato cannon is linear (straight line). In an engine the linear motion of the pistons is converted into rotational motion by the crankshaft. The rotational motion is nice because we plan to turn (rotate) the car's wheels with it anyway.

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My Car Engine Overhaul: A taste of my own medicine

My car had experienced an ‘over-hole’ last few days and it has caused me a bomb! Hehehe...
And, sadly to know that it happens because of my lack of knowledge about car engines and relying too much to other people.

Luckily a cousin of mine, (baweanese of course), had a friend who could 'kow-tim' this matter just by the tip of his fingers.. hihihi.. So, they helped me a lot to lessen the cost.

And, not less surprising, this guy, Mail, is very expert and has done a good job. He did it even better and did it more than a normal workshop will. I was there during part of the installation process.... And, for a not-so-knowledgeable lady like me, they were definitely amazing .. They cleaned everything and make everything look like sparkling new.. hehehe.

Thank you guys for your help .. I could fly back on the road with pride, feeling everything just like new!


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An evening with Abah

Gosh! A new posting at last!
After few idle days, finally I manage to write and post something to wake this blog up. So many things, so many events, so many on going activities... but I can't squeezed one little moment to, at least, use them here to freshen this blog with new info.

Flash back of 2008,

Tea with Abah at Mid Valley

Dec 23: a meeting with Hj Samri Barik, I used to call ‘Abah’, a Singaporean Baweanese. I met him for the first time online, but manage to meet him in real on his recent visits to KL. Abah came down together with family and a friend via KTM just for the purpose of leisure and visiting his old time friends.

How did I get into picture? Well … through internet, almost everything is possible nowadays. Don’t get me wrong, but this is one of the topics we’ve used for discussion during the meeting. Yes, we managed to know many new people through internet. That is so normal. But, to meet someone who is in Baweanese origin, that is wonders for me. Well at least, that was my first feeling when I first bump into someone from Bawean online. Thanx to Baweanese websites, blogs, and online forums creators and moderators, all of you has done a good job in looking forward into the new era of change through the world of internet. Of course, the transition will not be as smooth as planned, but we are hoping things will get improved by time.

The meeting was great. We shared and exchange information on life experiences, and from my young and immature thought, I found out there’s a huge gap between Baweanese Malaysian, Singaporean and Indonesian. Bawean at Bawean Island itself is fighting for their basic facilities; most common are the needs of electricity and proper transportation. Bawean in Malaysia is fighting with negative image by Indonesian illegal immigrant, improper management of work permits as well as dealing on how to get proper place for living. Whereas Bawean in Singapore, mostly are fighting on how to plan for better future, child education, life insurance and compensation for their retirement plan.

Well... of course there’ll be few exception cases on these categories, but I would want to say these as the most common from what I’ve learned so far. Nevertheless, I believe things will turn better and better somehow by the existence of awareness among Baweanese. They have proved this little by little; what we need is patience and get involved in supporting the process of improvement in whatever way possible.

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