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How piston rings work

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An engine is a simple mechanical device, an air pump really, that uses pistons and valves to pull air in and push air out. The pistons in an engine block must be sealed inside each cylinder in order for the process to be efficient. Because the pistons travel through the stroke millions of times throughout the life of the engine, the seals are critical. This is done with a series of rings that go around the top half of the piston, sealing it to the cylinder wall. When the piston rings wear out, the engine’s efficiency suffers. How they work Piston rings are made of metal, typical stock engines use cast iron rings, while high-performance engines  may use ductile iron rings with a chromoly or chrome face. Cast iron is good for stock rebuilds, but that is about it. Ductile iron rings are economical and good for performance engine builds. When left as is (no additional material facing), they are generally good to about two horsepower per cubic inch, so a naturally-aspirated 6...
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How fuel pumps at the gas station know when your gas tank is full?

How Does a  Fuel Pump  Know When to Stop?  Is there some sort of magical leprechaun in your tank that shouts up to a gremlin in the fuel pump, letting him know the tank is all full? Although, mystical automotive creatures would make the mechanics of automobiles more interesting and a blog about auto parts more Tolkien, this is not the case.   The automatic shutoff can be traced all the way back to 1939, so it is not the result of some modern nanotechnology. It is a simple system that relies heavily on vacuum. I am not talking about the vacuum that comes by when you lift up your legs so it can suck up the Cheetos lying beside your feet. The vacuum in a  fuel pump  nozzle is a Venturi effect. The effect is the reduction in pressure which results when a gas or fluid flows through a pipe, or in this case a nozzle. The next time you are at the pump look at the tip of the nozzle. You will see a hole on the side somewhere. This is where the Venturi port is lo...
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What is automatic voltage regulator (AVR)

An  automatic voltage regulator  (AVR) is a electronic device for automatically maintaining generator output terminal voltage at a set value under varying load and operating temperature. It controls output by sensing the voltage Vout at a power-generating coil and comparing it to a stable reference. The error signal is then used to adjust an average value of the field current. Most cheap portable generators have fixed excitation. In such machines, when an alternator is loaded, its terminal voltage drops due to its internal impedance. This impedance is formed of leakage reactance, armature reactance and armature resistance. The Vout also depends on the power factor of the load. That's why to maintain Vout within tighter limits, more expensive models use an  AVR.  Note that all AVRs help regulating the output in a steady state operation, but are generally slow to respond to fast transient loads. Some high-end models, such as Honda EB10000 use more accurate digital...
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8 STEPS TO INSTALL A BOATS DIESEL ENGINE

Ever wondered how a professional installs your boat’s  diesel engine  system? For insight into this highly technical process, we’ve outlined the steps below.  Please note, we do not recommend attempting to install an engine yourself and would always advise that you enlist the service of a qualified professional. A boat’s engine and drive system must be precisely aligned to minimise wear and vibration. However, the most carefully installed drive system can go out of  alignment when the boat is out of the water. Periodic checking and careful investigation of any untoward vibration or hull noise will pay dividends. 1， CHOOSE FLEXIBLE MOUNTS These comprise of steel shells with rubber bonded between them. Primarily, they insulate the hull from engine vibration. When choosing the correct size the  torque and thrust from the propeller must be taken into account. Once fitted, a professional should avoid at all costs spilling fuel or lubricating oil into the r...
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7 TIPS FOR DIESEL ENGINES

It is important for you to regularly keep up with your diesel engines maintenance so that these problems don’t arise out of the blue. Read on if you would like to learn more about how to maintain marine diesel engines. OVERHEATING ENGINE If your marine  diesel generator  is constantly overheating, it may be time to step back and examine the problem carefully. There are a number of reasons that it can get overheated such as: The piston cooling system failing to perform adequately which can lead to temperature rise. The piston rings of your marine diesel generator may have inadequate clearance or could be broken down and seized. Ring fault or failure can lead to leakage of combustion gases past the piston resulting in an increase of heat The lubrication system might be failing which can lead to overheating due to friction There may be valve timing issues resulting in poor combustion ENGINE NOT STARTING There could be a number of reasons why your dies...
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The Top 3 Things About Brake Calipers You Need to Know

1. What are  brake caliper s? A caliper is part of the disc brake system, the type most car's have in their front brakes. The brake caliper houses your car’s brake pads and pistons. Its job is to slow the car’s wheels by creating friction with the brake rotors. The brake caliper fits like a clamp on a wheel’s rotor to stop the wheel from turning when you step on the brakes. Inside each caliper is a pair of metal plates known as brake pads. When you push the brake pedal, brake fluid creates pressure on pistons in the brake caliper, forcing the pads against the brake rotor and slowing your car. 2. How are they connected to the rest of the braking system? The caliper assembly lives in your brakes and is connected to the master cylinder through tubes, hoses, and valves that conduct brake fluid through the system. We could go on about brake calipers for days on end, but we’ll show some restraint. Here’s what you really need to know: your brake calipers are really im...
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