Chery S11 / Chery QQ. Manual — part 107

Chery QQ Service Manual Body System

2.5.2.6 Crossbeam size

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Chery QQ Service Manual Body System

2.5.2.7 Reference point --- symmetry
Symmetrical reference points
Symmetrical reference points refer to the two corresponding points which are located
symmetrically on the centerline with same length, width and height; you can make use of the
symmetrical reference points to carry out high-speed check-up, so as to make sure that the
damage degree of bottom configuration parts of the vehicle body.

2.5.2.8 Reference points ___nonsymmetrical
Non-symmetrical reference points
The two points are non-symmetrical reference points when the two points possess different
dimensions. If you carry out high-speed check and the result measuring values are different, you
must check the measuring value according to the standard dimensions of vehicle body to see
whether or not the measuring points are symmetrical.

2.5.3 Diagnostic information and procedures
2.5.3.1 Inspection of alignment
You should make sure the alignment of bottom vehicle body with measuring gauge, while
carrying out the recommended measurement and check, measuring gauge assembly must include
the vertical indicator which stretch out 914mm.The following measurement can be carried out
with the measuring gauge:
● Point-to- point direct measurement
● Carry out computation measurement on the datum line of the level surface which is parallel to
the bottom vehicle body.
Set up one of the following indicator accordingly for every measuring point:
-

Height indicator

- Verticality indicator
Measure point-to-point distance on the following parts:
● Steering parts of front structure
● Suspension parts
Make sure that the vertical indicator is set up similarly
Under some certain circumstances, you can use one of the following tools to measure the
point-to-point distance directly:
● Tape measure
● Suitable measuring tools
Measure the dimension from the hole to the following positions:
● Forward position or core of the hole
● Aligning with the neighboring surface metal see “measurement – bottom vehicle body” for
reference, understand the following installation:
● measuring points arranged in alphabetical order
● Conversional data of dimension changing from the metric system to avoirdupois system

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Chery QQ Service Manual Body

System

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2.5.3.2 Inspection of alignment – bottom vehicle body
Three dimensional methods
It is necessary for the repair equipment to measure the length, height and width of many
measuring points simultaneously, it is also necessary for it to measure 2/3 of the vehicle body to
make things convenient for comparing the structure of vehicle body accurately.
General-purpose measuring system combines the use equipment with the technique to carry out
dimensional measurement including measurement of length, width and height.

2.5.4 Explanation and operation
2.5.4.1 Explanation of datum
Datum
Datum line is parallel to the bottom vehicle body or frame, and the above-mentioned surface is
the datum for all vertical measurement. Datum line is an imaginary level surface, it locates on the
bottom vehicle body, at the same time, and it is parallel to the bottom vehicle body. The height
results from distance measured from the datum line to the certain specified measuring point or
reference point of bottom vehicle body by means of vertical measurement. Dimension of height
is based on use equipment; it decides the position of datum line. Therefore, you can set different
datum lines for the same vehicle, you can plus and subtract the same numerical value from all
height to establish a new datum you need.

Centerline
Centerline is an imaginary vertical surface; it is vertical with the length direction of datum
surface, and pass through the vehicle centre. Centerline refers to the arbitrary straight lines
passing through the datum surface center of the vehicle.

Forming and perforation
Forming and perforation is a process of manufacture, which can form a region on the metal
structure easy for you to carry out three dimensional measurements. You can perforate a hole or
groove on that region easy for dimensional measurement and join together with other parts
structurally. All measuring results can be read-out from the centerline of a formed surface and
hole.
All dimensions can be measured from the following aspects:
● Length to the zero line (1)
● Height to the datum line (2)
● Width to the centre line (3)
All dimensions are symmetrical if there are no other regulations.

Chery QQ Service Manual

Mechanical Part of SQR 472Engine

1

SQR 472 Engine

（Service Manual for Mechanical Part）