1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156 
What is the correct procedure for checking the front wheal
Page 109
If you've noticed an error in this article please click here to report it so we can fix it.
track to make sure that the rear axles are running true (i.e. that the wheel is not "crabbing") on a rigid eight-wheeler?
AA diagonal check should be made of the
chassis frame by taking a measurement from the nearside rear corner to the offside front corner and from the offside rear corner to the nearside front corner, to ensure that the frame is, in fact, square.
Once this is established, any datum line on the chassis frame can be used as a measuring point to the centres of the two rear axles at each side. It is best to take the measurement to the axle shaft casing as this gives a positive location. A straight edge placed along the wheel rims will show whether or not the axles have shifted laterally. If you find it impossible to reach the wheel rims with the straight edge. then this should be aligned with the chassis frame and measurements taken from inside the straight edge to the wheel rim.
On no account should readings be taken from front axle to ensure that rear axles are running through. Once you have obtained a datum line from which you may check the rear axle position, the same point can also be used to check correct alignment of the front axles.
The accurate method of checking alignment of the front axles is to use a sight gauge and one should first check the two axles individually for track. When you are sure that this is correct, the reflecting mirror should be fitted to the trammel in the right angle position and the location bars should be offered up to the outside of the leading rear axle.
With the sight gauge also mounted in the right-angle position on its trammel bar, this should be set in the zero position and the locating bar placed against the first steeringaxle wheel rim. The steering should now be moved until the datum line of the gauge is shown at the centre of the two marker lines on the reflector screen.
At this point, it is advisable to lash the steering wheel so that this will not move while adjustments are taking place on the drag link to the second steering axle. Keeping the sight gauge on the zero position, the second axle drag link should be lengthened or shortened, in accordance with whether the axle is steering to the off or near side. When a satisfactory reading is obtained, the drag link should be locked up. As a final check on the overall alignment of the vehicle, the reflecting mirror trammel should now be placed with its locating bars on the rearmost trailing axle while the sight gauge assembly is placed against the first steering axle. Without any adjustment to the sight gauge reading, one should see the datum line disposed centrally between the two marker lines on the reflector screen.
If your workshop does not include a sight steering alignment gauge, the chassis frame must be measured off at two points which would enable you to strike a line parallel to the frame. Measurements taken from leading and trailing edges of the four wheels on one side will show if the bogie or steering gear is out of alignment.