Page 34 - CTS - Mechanic Diesel - TP

MECHANIC DIESEL - CITS

MODULE 2: Engine System

EXERCISE 2.1: Perform vacuum test

Objectives

At the end of this exercise you shall be able to
• installing vacuum gauge
• testing the vacuum in different stages
• concluding the results.

Requirements

Tools/Materials

• A petrol vehicle in running condition
• Combination plier
• Vacuum gauge

Introduction

The vacuum test is performed in an engine to know the condition of the engine and with the results we can have
a conclusion of whether the engine need reconditioning or not.

Procedure

• Place the vehicle in a level ground.
• Switch off engine.
• Open the bonnet.

• Locate the vacuum line in the engine intake manifold.
• Disconnect the vacuum connection from the component where it is connected and not from the intake manifold
• Connect the vacuum gauge with the vacuum line.
• Start the engine.
• Allow the engine to run idle.
• Note down the reading shown in the vacuum
gauge.
• The vacuum of the engine during idle is _________
in- Hg.

• Slowly raise the engine till the engine speed
reaches approximately 2500 rpm. And measure
the vacuum again.
• The vacuum during 2500 rpm is _______ in-Hg.
• slow down the engine speed.
• Raise the engine speed suddenly and release it immediately.
• Note down the vacuum reading.

• The vacuum during sudden raise and release are ______ in Hg.
• Based on the readings obtained, conclude the condition of the engine.

17