Engineering Explained - Perda de potencia ao longo do tempo

Este fórum contém explicações e/ou descrições técnicas sobre mecânica, técnicas de manutenção, informação sobre peças, etc.

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amandio
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Engineering Explained - Perda de potencia ao longo do tempo

Mensagem por amandio » 01 nov 2017 10:06

Sabemos que o motor perde potência ao longo dos anos com o uso ou mesmo a falta dele.
Aqui ficam as razões por que acontece, causas e cuidados a ter para uma manutenção periódica do motor para mantê-lo saudável.
E isto aplica-se a qualquer tipo de tecnologia: carburador ou injecção.

10 Reasons Why Engines Lose Power Over Time

There are four things a gasoline engine requires to generate power and almost any engine problem will come down to something relating to one of these four factors. 1. Air 2. Fuel 3. Compression 4. Spark

Dirty Air Filter
A clogged air filter makes the engine work harder to pull in air, and can restrict the maximum amount of air let in. Less air means less power.

Exhaust Restrictions
The engine will have to work harder to push out exhaust gases, limiting power. Catalytic converters can clog up on engines with an improper air/fuel mixture or as a result of fuel additives reacting within. Mufflers can also fail internally, and alterations of the internal piping can result in an airflow restriction.

Fuel Injectors
Deposits can build up on the injectors over time from heat soak or poor fuel. Small restrictions can cause the O2 sensors to read a lean mixture, and so more fuel will be added to compensate. This can result in a rich mixture for the cylinders without injector problems, or even misfiring if the injector isn’t capable of injecting enough fuel.

Fuel Pumps
Overtime the fuel pump can wear out, but it might not necessarily fail catastrophically. While it may still be able to supply fuel at lower pressures, it may begin to struggle to provide fuel at higher pressures or for longer durations.

Worn Piston Rings
One of the major things that can happen over time is the piston rings will wear down, and this will allow for blow-by. Some of the high pressure air and fuel mixture combusting will pass by the pistons and travel along the cylinder walls into the crank case. This is pressure that should be pressing the piston down, so power is lost. It also means less compression as some of the air can escape as the piston travels upward on the intake stroke.

Carbon Deposits On Intake Valves/Valve Seats
If carbon deposits build up on the valves or valve seats, this can prevent the valves from closing properly. If an intake valve cannot fully close, it will allow air to escape during the compression stroke, effectively lowering the compression ratio.

Carbon Deposits On The Piston
If deposits build on the piston or cylinder walls, these deposits can create hot spots. These hot spots can result in engine knock if conditions allow for it. If the engine is capable, it will retard the ignition timing to reduce the likelihood of knock. By retarding the ignition timing, power is lost.

Fouled Spark Plugs
Spark plugs can build deposits with time. Inconsistent spark plug firing means you’re likely to misfire. Maintaining clean plugs ensures that the spark part of the equation doesn’t result in a loss of power.


Fonte: Engineering Explained

https://youtu.be/uj8hjAjI7p4
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JoseMorgado
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Re: Engineering Explained - Perda de potencia ao longo do te

Mensagem por JoseMorgado » 21 nov 2017 11:59

Muito interessante!!
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Re: Engineering Explained - Perda de potencia ao longo do te

Mensagem por amandio » 21 nov 2017 13:33

Claro está que ter qualquer veículo parado por longos períodos também não ajuda muito.
A condensação, oxidação dos metais e borrachas secas são as maiores consequências. :roll:
Amândio de Aveiro
(da Madeira, que já esteve em Oeiras e agora em Oslo)
R1150 GS [2002-2013]

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