Chassis Straightness Check - Lotus Evora Service Notes

Lotus Service Notes
in significant bending, tearing or distortion of the aluminium structure, especially in respect of the attachment
points for the front and rear subframes, the recommended repair is to renew the partial body assembly, which
comprises the main chassis tub, with jig bonded composite rear bulkhead, body sills and windscreen frame.
Also included are the pipes and cables routed through the body sill mouldings.
AJ.2 - CHASSIS STRAIGHTNESS CHECK
In the absence of visual damage, the chassis may be checked for twist or distortion by utilising the machined
tooling indents in the underside of the main side rails. If computer processed laser measuring equipment is not
available, manual checks can be made with reference to a completely level ground plane, e.g. an accurately
set and maintained suspension geometry ramp/lift. Position the car on the lift, and proceed as follows:
1. Identify the tooling indents in the lower surface of each chassis main side rail. At the front end, just behind
the front crossmember, and at the rear, just ahead of the fuel tank bay rear crossmember. Note that three
of the machined oval areas are drilled, but not at the left hand rear.
2. Measure the height of each tooling indent above the reference plane and use jacks to adjust the height of
the chassis in order to equalise any three of these dimensions.
3. Measure the deviation of the fourth dimension from the other three.
Maximum service deviation = ± 2.0 mm.
4. Repeat operations (2) and (3) for each combination of corners to result in four values for the 'fourth' dimen-
sion deviation. If any one of these exceeds the service specification, the chassis should be considered
damaged and replaced by a partial body assembly.
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Illustration to follow
Section AJ