The document discusses the working principles of 4-stroke gasoline engines and diesel engines. For gasoline engines, it describes the 4 steps of induction, compression, ignition, and emission. It explains how the intake of air-fuel mixture, compression, combustion, and exhaust occur through the upward and downward movement of the piston in the cylinder. For diesel engines, it states that combustion occurs due to high temperatures from compression rather than a spark plug. Both engines convert the chemical energy of fuel into heat energy and then mechanical energy through the reciprocating motion of the piston.

1. Prinsip kerja motor bakar 4 tak
Posted on 1 Februari 2011 by ridertua
4-stroke combustion engine cycle:
1. Induction (bahan bakar masuk)
2. Compression(kompresi)
3. Ignition (pembakaran)
4. Emission (pembuangan)
Ayo coba mengingat kerja mesin 4 tak…..
1.Langkah Hisap (induction)
Klep isap terbuka,klep buang tertutup,piston bergerak kebawah,udara & bahan bakar masuk
ruang bakar.
2.Langkah Kompressi(Compression)
Klep isap & buang tertutup,piston bergerak ke atas bahan bakar dimampatkan.
3.Langkah Pembakaran(Ignition)
Klep isap & buang masih tertutup,sebelum piston tepat sampai ke atas (top) busi memercikkan
api membakar udara plus bahan bakar dan terjadi ledakan yang menekan piston ke bawah.
4.Langkah buang(Emission)
Setelah piston mencapai langkah akhir klep buang terbuka,dan piston bergerak keatas menekan
gas sisa pembakaran.klep isap masih tertutup.

2. Begitu seterusnya…kembali ke nomor 1.
PERBEDAAN CARA KERJA MOTOR BAKAR BENSIN DENGAN MOTOR BAKAR
SOLAR
Filed Under (Mesin Mobil ) by Dion Yerry on Sabtu, 27 Februari 2010
Posted at : 00:29
Motor bakar adalah mesin atau pesawat yang menggunakan energi termal untuk melakukan kerja
mekanik, yaitu dengan cara merubah energi kimia dari bahan bakar menjadi energi panas, dan
menggunakan energi tersebut untuk melakukan kerja mekanik. Energi termal diperoleh dari
pembakaran bahan bakar pada masin itu sendiri. Jika ditinjau dari cara memperoleh energi termal ini
(proses pembakaran bahan bakar), maka motor bakar dapat dibagi menjadi 2 golongan yaitu: motor
pembakaran luar dan motor pembakaran dalam.
I. Motor pembakaran luar
Pada motor pembakaran luar ini, proses pembakaran bahan bakar terjadi di luar mesin itu,
sehingga untuk melaksanakan pembakaran digunakan mesin tersendiri. Panas dari hasil
pembakaran bahan bakar tidak langsung diubah menjadi tenaga gerak, tetapi terlebih dulu
melalui media penghantar, baru kemudian diubah menjadi tenaga mekanik. Misalnya pada ketel
uap dan turbin uap.
II. Motor pembakaran dalam
Pada motor pembakaran dalam, proses pembakaran bahan bakar terjadi di dalam mesin itu
sendiri, sehingga panas dari hasil pembakaran langsung bisa diubah menjadi tenaga mekanik.
Misalnya : pada turbin gas, motor bakar torak dan mesin propulasi pancar gas.
A. Prinsip Kerja Motor bakar Bensin
Pada motor bensin, bensin dibakar untuk memperoleh energi termal. Energi ini selanjutnya
digunakan untuk melakukan gerakan mekanik. Prinsip kerja motor bensin, secara sederhana
dapat dijelaskan sebagai berikut : campuran udara dan bensin dari karburator diisap masuk ke
dalam silinder, dimampatkan oleh gerak naik torak, dibakar untuk memperoleh tenaga panas,
yang mana dengan terbakarnya gas-gas akan mempertinggi suhu dan tekanan. Bila torak
bergerak turun naik di dalam silinder dan menerima tekanan tinggi akibat pembakaran, maka
suatu tenaga kerja pada torak memungkinkan torak terdorong ke bawah. Bila batang torak dan
poros engkol dilengkapi untuk merubah gerakan turun naik menjadi gerakan putar, torak akan
menggerakkan batang torak dan yang mana ini akan memutarkan poros engkol. Dan juga
diperlukan untuk membuang gas-gas sisa pembakaran dan penyediaan campuran udara bensin

3. pada saat-saat yang tepat untuk menjaga agar torak dapat bergerak secara periodik dan
melakukan kerja tetap.
Kerja periodik di dalam silinder dimulai dari pemasukan campuran udara dan bensin ke dalam
silinder, sampai pada kompresi, pembakaran dan pengeluaran gas-gas sisa pembakaran dari
dalam silinder inilah yang disebut dengan “siklus mesin”. Pada motor bensin terdapat dua
macam tipe yaitu: motor bakar 4 tak dan motor bakar 2 tak. Pada motor 4 tak, untuk melakukan
satu siklus memerlukan 4 gerakan torak atau dua kali putaran poros engkol, sedangkan pada
motor 2 tak, untuk melakukan satu siklus hanya memerlukan 2 gerakan torak atau satu putaran
poros engkol.
B. Cara Kerja Motor Bensin 4 Langkah
Torak bergerak naik turun di dalam silinder dalam gerakan reciprocating. Titik tertinggi yang
dicapai oleh torak tersebut disebut titik mati atas (TMA) dan titik terendah disebut titik mati
bawah (TMB). Gerakan dari TMA ke TMB disebut langkah torak (stroke). Pada motor 4 langkah
mempunyai 4 langkah dalam satu gerakan yaitu langkah penghisapan, langkah kompresi ,
langkah kerja dan langkah pembuangan. B.1.
Langkah hisap
Pada gerak hisap, campuran udara bensin dihisap ke dalam silinder. Bila jarum dilepas dari sebuah alat
suntik dan plunyernya ditarik sedikit sambil menutup bagian ujung yang terbuka dengan jari (alat suntik
akan rusak bila plunyer ditarik dengan tiba-tiba), dengan membebaskan jari akan menyebabkan udara
masuk ke alat suntik ini dan akan terdengar suara letupan. Hal ini terjadi sebab tekanan di dalam lebih
rendah dari tekanan udara luar. Hal yang sama juga terjadi di mesin, torak dalam gerakan turun dari TMA

4. ke TMB menyebabkan kehampaan di dalam silinder, dengan demikian campuran udara bensin dihisap ke
dalam. Selama langkah torak ini, katup hisap akan membuka dan katup buang menutup.
B.2. Langkah kompresi
Dalam gerakan ini campuran udara bensin yang di dalam silinder dimampatkan oleh torak yang bergerak
ke atas dari TMB ke TMA. Kedua katup hisap dan katup buang akan menutup selama gerakan tekanan
dan suhu campuran udara bensin menjadi naik. Bila tekanan campuran udara bensin ini ditambah lagi,
tekanan serta ledakan yang lebih besar lagi dari tenaga yang kuat ini akan mendorong torak ke bawah.
Sekarang torak sudah melakukan dua gerakan atau satu putaran, dan poros engkol berputar satu
putaran.
B.3. Langkah kerja
Dalam gerakan ini, campuran udara bensin yang dihisap telah dibakar dan menyebabkan terbakar dan
menghasilkan tenaga yang mendorong torak ke bawah meneruskan tenaga penggerak yang nyata.
Selama gerak ini katup hisap dan katup buang masih tertutup. Torak telah melakukan tiga langkah dan
poros engkol berputar satu setengah putaran.
B.4. Langkah buang
Dalam gerak ini, torak terdorong ke bawah, ke TMB dan naik kembali ke TMA untuk mendorong gas-gas
yang telah terbakar dari silinder. Selama gerak ini kerja katup buang saja yang terbuka. Bila torak
mencapai TMA sesudah melakukan pekerjaan seperti di atas, torak akan kembali pada keadaan untuk
memulai gerak hisap. Sekarang motor telah melakukan 4 gerakan penuh, hisap-kompresi-kerja-buang.
Poros engkol berputar 2 putaran, dan telah menghasilkan satu tenaga. Di dalam mesin sebenarnya,
membuka dan menutupnya katup tidak terjadi tepat pada TMA dan TMB, tetapi akan berlaku lebih
cepat atau lambat, ini dimaksudkan untuk lebih efektif lagi untuk aliran gas.
A. Prinsip Kerja Motor bakar solar
Motor diesel dikategorikan dalam motor bakar torak dan mesin pembakaran dalam (internal combustion
engine) (simplenya biasanya disebut “mobor bakar” saja). Prosip kerja motor diesel adalah merubah
energi kimia menjadi energi mekanis. Energi kimia di dapatkan melalui proses reakasi kimia
(pembakaran) dari bahan bakar (solar) dan oksidiser (udara) di dalam silinder (ruang bakar).
Pada motor diesel ruang bakarnya bisa terdiri dari satu atau lebih tergantung pada penggunaannya dan
dalam satu silinder dapat terdiri dari satu atau dua torak. Pada umumnya dalam satu silinder motor
diesel hanya memiliki satu torak.
Prinsip Kerja
Tekanan gas hasil pembakaran bahan bakan dan udara akan mendorong torak yang dihubungkan
dengan poros engkol menggunakan batang torak, sehingga torak dapat bergerak bolak-balik
(reciprocating). Gerak bolak-balik torak akan diubah menjadi gerak rotasi oleh poros engkol
(crank shaft). Dan sebaliknya gerak rotasi poros engkol juga diubah menjadi gerak bolak-balik
torak pada langkah kompresi.
Perbedaan antara motor diesel dan motor bensin yang nyata adalah terletak pada proses pembakaran
bahan bakar, pada motor bensin pembakaran bahan bakar terjadi karena adanya loncatan api listrik
yang dihasilkan oleh dua elektroda busi (spark plug), sedangkan pada motor diesel pembakaran terjadi

5. karena kenaikan temperatur campuran udara dan bahan bakar akibat kompresi torak hingga mencapai
temperatur nyala. Karena prinsip penyalaan bahan bakarnya akibat tekanan maka motor diesel juga
disebut compression ignition engine sedangkan motor bensin disebut spark ignition engine.
TRANSLATE
Motor fuel is the engine or aircraft that use thermal energy to mechanical work, ie by changing the
chemical energy of fuel into heat energy, and use that energy to perform mechanical work. Thermal
energy derived from fuel combustion in the managements themselves. If viewed from how to obtain
this thermal energy (fuel combustion process), then the motor fuel can be divided into 2 groups,
namely: external combustion motor and a combustion motor.
I. External combustion motor
In this external combustion motor, the fuel combustion process takes place outside the machine, so to
conduct its own combustion engine use. The heat from the combustion of fuel is not directly converted
into energy of motion, but first conductor through the media, and then converted into mechanical
energy. For example in the boiler and steam turbine.
II. Combustion motor
In internal combustion motor, the fuel combustion process occurs in the machine itself, so that the heat
from the combustion can be converted directly into mechanical energy. For example: in a gas turbine,
piston motor fuel and gas engines emit propulasi.
A. Working Principle Motor Gasoline fuel
In motor gasoline, gasoline burned to obtain thermal energy. This energy is then used to perform
mechanical movement. Gasoline motor working principle, can simply be explained as follows: a mixture
of air and fuel from the carburetor sucked into the cylinder, compressed by the piston moving up,
burned for heat energy, which is the combustion gases will increase the temperature and pressure.
When the piston moves up and down in the cylinder and receive a high pressure due to combustion,
then a labor allows the piston driven piston downward. When the piston rod and crankshaft equipped to
transform the movement into the movement up and down round, will move the piston and piston rod
which is going to rotate crankshaft. And also needed to remove the remaining gases and combustion air
mixture gas supply at the right time to keep the piston can move and perform periodic steady work.
Periodic employment in the cylinder starting from entry of air and fuel mixture into the cylinder, until
the compression, combustion and spending the remaining gases from the combustion in the cylinder is
called the "machine cycle". In gasoline motors, there are two types namely: motor fuel and motor 4 can
not burn 2 no. In the motor 4 stroke, to make one cycle requires 4 piston movement or twice crankshaft
rotation, whereas the motor 2 does not, for one cycle only takes 2 piston movement or a crankshaft

6. rotation.
B. How it Works Step 4 Motor Gasoline
Piston moves up and down in the cylinder in a reciprocating motion. The highest point reached by the
piston dead point mentioned above (TMA) and the lowest point is the point to die down (TMB).
Movement of the TMA to the TMB is called step piston (stroke). The motor has 4 steps 4 steps in a
movement that is exploitation step, compression step, step-step work and disposal. B.1. Step suction
On motion of suction, air fuel mixture is sucked into the cylinder. When the needle is removed from a
syringe and pulled plunyernya little, closing the open end of the finger (a syringe would be damaged if
plunyer withdrawn abruptly), by freeing the finger will cause the air into the syringe and will pop sound.
This occurs because the pressure inside is lower than the outside air pressure. The same thing happened
in the engine, piston in the down movement of the TMB TMA caused a void in the cylinder, so the air
fuel mixture is sucked into the. During this step piston, suction valve will open and close the relief valve.
B.2. Step compression
In this movement of air fuel mixture in the cylinder is compressed by the piston moving upward from
the TMB to the TMA. Both suction valve and exhaust valve will be closed during the movement of
pressure and temperature of the air fuel mixture to rise. When the pressure of the air fuel mixture is
added again, the pressure and greater explosion from this powerful force will push piston down. Now
piston is made of two movements, or one round, and the crankshaft rotates one revolution.
B.3. Step work
In this movement, the fuel air mixture has been burned and inhaled causing burns and produces a force
that drives the piston to continue the real driving force. During this motion suction valve and exhaust
valve is still closed. Piston has to do three steps and the crankshaft rotates a half turn.
B.4. Step away
In this motion, piston pushed down, the TMB and climbed back into the TMA to push gases that have
been burned from the cylinder. During this movement of work relief valves are open. When the piston
reaches TMA after doing the job as above, piston will return to the state to start the suction motion.
Now the motor has done 4 full movement, suction-compression-work-waste. Spinning crankshaft 2
turns, and has produced a strength. In the actual machine, opening and closing the valve does not occur
just in TMA and TMB, but will apply more sooner or later, is intended to be more effective for the gas
flow.
A. Working principle of diesel motors
Categorized diesel motor fuel in the motor piston and the combustion engine (internal combustion
engine) (simplenya usually called "mobor burn" only). Diesel motor Prosip work is changing chemical
energy into mechanical energy. Chemical energy in reakasi get through the process of chemical
(combustion) of fuel (diesel) and oksidiser (air) in the cylinder (the engine).
In the diesel motor fuel can consist of one or more depending on its use and in one cylinder can consist

7. of one or two piston. In general, in one cylinder diesel motor has only one piston.
Working Principle
The pressure of the gas and biofuel combustion air will push piston is connected to crankshaft using
piston rod, so the piston can move back and forth (reciprocating). Alternating motion piston is
converted into rotational motion by crank shaft (crank shaft). And vice versa crankshaft rotational
motion is also converted into alternating motion of piston in the compression step.
The difference between diesel and motor gasoline motor which is located on the actual process of fuel
combustion, the combustion of gasoline motor fuel due to the fire jumps the electricity produced by the
two-electrode spark plug (spark plug), while the diesel motor combustion occurs due to an increase in
mixture temperature air and fuel due to the compression piston to achieve a flame temperature.
Because the principle of the fuel ignition due to the pressure of diesel motors are also called
compression ignition gasoline engine while the motor is called spark ignition engines.
DIESEL ENGINE TO WORK
Posted by Performance Of Engine 00:16 Label: Car Engine 0 comments
Old Diesel Power Compared with today's diesel technology yg dg common reel dilangkapi direct
injection (CRD), an old diesel technology produces only about half the power and torque about a third.
The main cause is the pressure stability injenksi where pre-generated reply CRD pressured almost
constant for intervals long enough RPM reply. Whereas in the old diesel (conventional), the maximum
injection pressure is only achieved at certain RPM, because I get pressure with the pump work in
accordance with the reply round machine. Sadder if conditions are not good nozzle, fuel spray
pengkabutan not necessarily optimal manghambat combustion. Power and torque produced by the
lower reply. We must be diligent in cleaning and nozzle set at any time. I have a tip for you kutak starry-
kutik old diesel engine. The principle is to heat the fuel to facilitate nozzle pengkabutan although
conditions are not good. This technique actually has a lot of people do. But most of the way to enter the
fuel hose to the tube of oil or radiator. Such a way that is less good, because the fuel becomes heat
when entering the injection pump. In addition to damaging the pump, the fuel temperature was falling
at the time of reaching nozzle. Pump pressure was not maximal because of the high temperature. So the
pressure at the nozzle to achieve shrinkage due to temperature decrease. Who best ways I have
suggested is the heating fuel after passing through the injection pump. Note the original construction of
your diesel engine, much like the picture above. Which must be heated is a tube connecting the
injection pump with the nozzle. One way is by passing some of the smoke exhaust (exhaust) from the
header through the exaust pipe (small) mounted close to the tube / pipe nozzle as the red piping reply
was in the picture below iini. We recommend that the distance between the split dg exhaust pipe nozzle
pipe can be arranged to obtain the most optimal conditions. This split exhaust pipes can go back to
exhaust again at the end, but it should just get out bablas dg exhaust pipe parallel to avoid prejudicial
barriers engine power. This image is only a simple chart. Implementation would have to really pay
attention to the construction of your engine exhaust heat does not bother split other components. The

8. advantage of this technique include: 1. Injection pump is not perturbed by normal fuel temperature. 2.
Fuel pressure when it reaches the nozzle increases as the temperature rises and the volume of fixed
(rule provisions of PV / T) 3. The combination temperature and high pressure fuel in the nozzle easier
when pengkabutan and combustion processes. 4. No matter how small, additional pressure will increase
on kompressi during combustion piston reply would be to add power and torque. Disadvantages /
weaknesses of this technique is only effective if the placement of exhaust split, too close to the air inlet
(intake manifold), thus reducing the air supply pressure (due to be considered open space) can result in
lower yg kompressi during combustion.