KATA PENGANTAR

Puji syukur kehadirat Allah SWT atas segala limpahan rahmat dan

hidayahnya sehingga penulis dapat menyelesaikan laporan praktikum prestasi

mesin ini.

Laporan ini disusun dalam rangka menyelesaikan tugas praktikum di

Jurusan Teknik Mesin STITEKNAS JAMBI. Penulis menyadari bahwa tanpa

bantuan dan bimbingan dari berbagai pihak dan dosen tidak akan terlaksana

dengan baik. Tidak ada yang dapat penulis berikan sebagai ungkapan balas budi

selain doa, semoga Allah SWT memberikan balasan atas segala kebaikannya.

Penulis telah berusaha sebaik baiknya untuk menyelesaikan laporan ini

dan berharap semoga laporan dapat bermanfaat bagi pihak yang berkepentingan

kelak. Dengan hati ikhlas dan tangan terbuka dinantikan pendapat, kritikan dan

saran yang bersifat konstruktif demi menambah wawasan dan pengetahuan

penulis.

Untuk kesempatan ini penulis ucapkan terimakasih kepada yang

terhormat:

1. Bapak DR. Suratno, M.Pd selaku ketua STITEKNAS Jambi

2. Bapak M. Ficky A, S.Si. M.Si selaku Kepala Laboratorium Teknik

Mesin dan dosen dari praktikum prestasi mesin di Stiteknas Jambi.

3. Alten P. Pardosi, S.T. selaku asisten dosen praktikum prestasi mesin.

4. Marwan Efendi selaku asisten dosen praktikum prestasi mesin.

5. Rudi Hartono selaku asisten dosen praktikum prestasi mesin.

6. M. Ardian selaku asisten dosen praktikum prestasi mesin.

7. Semua pihak yang terkait yaitu teman-teman yang telah membantu

dalam menyelesaikan laporan praktikum prestasi mesin ini.

Jambi, 20 mei 2015

Penulis

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DAFTAR ISI

LEMBAR PENGESAHAN

ABSTRAK

KATA PENGANTAR.....................................................................................................................i

DAFTAR ISI.......................................................................................................................................ii

DAFTAR GAMBAR..........................................................................................................................iv

DAFTAR TABEL ..............................................................................................................................v

DAFTAR SIMBOL.............................................................................................................................vi

BAB I PENDAHULUAN...................................................................................................................1

1.1 Latar Belakang.................................................................................................................2

1.2 Rumusan Masalah............................................................................................................2

1.3 Tujuan Praktikum.............................................................................................................3

1.4 Manfaat Praktikum..................................................................................................4

1.5 Batasan masalah...............................................................................................................4

1.6 Sistematika penulisan..............................................................................................5

BAB II KAJIAN PUSTAKA.............................................................................................................6

2.1 Sejarah perkembangan motor bakar.................................................................................6

2.2 Pengertian umum motor bakar.........................................................................................8

2.3 Menurut siklus motor bakar ............................................................................................9

2.3.1 Langkah isap..................................................................................................10

2.3.2 Langkah kompresi.......................................................................................11

2.3.3 Langkah usaha.............................................................................................12

2.3.4 Langkah buang............................................................................................13

2.4 Sistem bahan bakar..........................................................................................................19

2.4.1 Bahan bakar premium.....................................................................................19

2.4.2 Nilai oktan...................................................................................................21

2.4.3 Perbandingan bahan bakar dan udara..........................................................22

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2.5 karburator.............................................................................................................24

2.5.1 Fungsi karburator........................................................................................24

2.5.2 Prinsip kerja karburator...............................................................................25

2.6 Hukum termodinamika....................................................................................................28

2.7 Persamaan Benoulli..........................................................................................................30

2.8 Torsi dan daya .......................................................................................................31

BAB III METODE PENELITIAN......................................................................................................32

3.1 Skema gambar pengujian.................................................................................................32

3.2 alat Uji..............................................................................................................................34

3.2.1 Gelas ukur.....................................................................................................34

3.2.2 Tacho Meter................................................................................................35

3.2.3 Kompersi tester...........................................................................................36

3.2.4 Stop watch ..................................................................................................37

3.3 Prosedur pengujian ..........................................................................................................38

3.3.1 Persiapan sebelum pengujian...........................................................................38

3.3.2 Prosedur menghidupkan dan mematikan mesin..........................................39

3.4 Tabel data.........................................................................................................................41

3.5 Diagram alir.....................................................................................................................42

BAB IV PEMBAHASAN...................................................................................................................43

4.1 Tabel hasil pengujian ......................................................................................................43

4.2 Grafik...............................................................................................................................44

4.3 Analisa.............................................................................................................................47

BAB V PENUTUP..............................................................................................................................49

5.1 Kesimpulan......................................................................................................................49

5.2 Saran.................................................................................................................................49

DAFTAR PUSTAKA

LAMPIRAN

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