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Lotus Eleven/Elise/Exige. Manual - part 59

Lotus Service Notes Section HG

Page 2

General Layout

Upper column

assembly

mountings

Track rod

end

Intermediate

column

Lower

u/j

Upper u/j

Rack mounting

plinth

Thrust pad

adjuster

Rack housing

Gaiter

Track rod

h55

HG.1 - GENERAl DESCRIPTION

The steering system of the Elise comprises a telescopically collapsible upper column assembly, connecting

to a rigidly mounted rack and pinion assembly via a universally jointed intermediate shaft. The steering rack

tie rods connect to rearward facing steering arms bolted to the forged steel front hub carriers, with geometry

providing 30% Ackermann effect, and a toe-out on bump characteristic. No power assistance is provided.

Prior to June '04, the steering rack assembly used a one-piece, alloy, pinion/rack housing, superseded

after that time by a cast alloy pinion housing mated to a tubular steel rack housing.

The upper column is fixed to the scuttle beam, with the column upper bearing carrier also providing

mountings for the steering lock and column switches. 'Break out' inserts fitted in the column upper mounting

flanges, allow for telescoping of the column in a frontal collision. The steering rack assembly, which provides

2.4 turns from lock to lock at a 15.8:1 ratio, is rigidly mounted inside a chassis transverse extrusion behind the

top wishbone rear pivots.

HG.2 - STEERING WHEEl

Non Airbag Type: The alloy three spoke steering wheel, has a leather trimmed rim and moulded rubber cov-

ered spokes, and is secured to the column via a 36 spline boss. The horn button is mounted in the steering

wheel centre pad which is supported by a collapsible steel spider bolted to the hub of the wheel. The positive

feed to the horn button is supplied via a spring loaded contact housed in the column switch carrier, and a slip

ring mounted on the forward side of the wheel. The earth contact of the button is connected to a terminal on

the spider.

Airbag Type: The alloy three spoke steering wheel has a leather trimmed rim and moulded rubber covered

spokes which incorporate horn buttons in the outer ends of each of the nominally horizontal spokes. An airbag

Lotus Service Notes Section HG

Page 3

module is incorporated in the centre of the wheel, and uses a rotary coil unit to maintain cable continuity to the

airbag and horn buttons.

To Remove Steering Wheel (non airbag)

1. Pull off the centre trim pad with horn but-

ton, and disconnect the two horn leads.

2. To allow access for a steering wheel

puller tool, it is necessary first to remove

the column shroud:

Release the four screws securing the

shroud upper section, turning the steering

wheel as necessary to permit access.

Pull out the grommet from around the

ignition switch, and remove the three

screws securing the lower shroud.

If necessary, disconnect or remove the

trip/panel lights control button from the

lower shroud.

3. Remove the nut securing the steering wheel boss to the column. Match mark the boss and column to

enable alignment to be maintained on re-assembly.

4. Use a suitable steering wheel puller tool to locate behind the steering wheel boss and bear against the

end of the column.

CAUTION: If excessive force is applied to either the wheel or column without an appropriate puller,

the telescoping mechanism of the outer column may be overridden, necessitating column replace-

ment.

5. If necessary, unclip the slip ring from the steering wheel boss and withdraw with the horn lead. Withdraw

the column bearing preload spring.

6. To refit the steering wheel, reverse the above procedure with the following notes:

Clip the horn slip ring to the steering wheel boss with the turn indicator cancelling vane on the left hand

side.

Ensure that the column bearing preload spring is fitted over the inner column before fitting the wheel with

the match marks aligned. If re-alignment is necessary, see later.

Torque tighten the steering wheel to column nut to 25 Nm.

Column upper shroud

Lower shroud

mounting

bracket

Column lower

shroud

b258a

Lotus Service Notes Section HG

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To Remove Steering Wheel (airbag type)

WARNING: The driver's airbag is housed in the hub of the steering wheel. Precautions need to

be taken for personal safety when working with airbags and associated componentry. Do not attempt

to remove the airbag or steering wheel without first referring to section WD.

On the back of the airbag type steering wheel hub, is mounted a 'rotary connector', being a device which

allows the steering wheel to turn whilst maintaining electrical continuity to the airbag module and horn buttons.

This device needs to be centralised before fitting, or breakage will result. Follow instructions below carefully.

1. Column shrouds: Remove the two screws retaining the top part of the shroud, and the four screws retaining

the lower part, and withdraw both parts from the column, if necessary disconnecting the trip/panel lights

control button from the lower shroud.

2. Refer to section WD to remove the airbag module from the wheel.

3. Disconnect the horn harness plug.

4. The steering wheel may be released from the hub by removing the four attaching screws.

5. To remove the hub, or wheel and hub assembly from the column, first ensure the front wheels are pointing

straight ahead. Bend back the locking tabs and release the nut securing the hub to the column. Before at-

tempting to remove the hub, match mark the position of the hub against the column to aid re-assembly.

6. Using a suitable steering wheel puller tool, position the legs to reach through the holes in the wheel hub

and bear directly against the hub, without intefering with the rotary connector on the back of the hub. The

centre screw should bear against the end of the column. Withdraw the wheel/hub/rotary connector as-

sembly from the column splines.

Alternatively, for better puller access, the steering wheel can first be removed from the hub by releasing

the four retaining screws.

CAUTION: If excessive force is applied to either the wheel/hub or column without an appropriate

puller, the telescoping mechanism of the outer column may be overridden, necessitating column

replacement.

Refitment

7. If the hub is already fitted to the column, refit the steering wheel to the hub and tighten the four fixing

screws. Mate the horn buttons harness connector plug.

8. If fitting the wheel/hub/rotary connector assembly to the column, the rotary connector must first be central-

ised: Turn the connector centre element fully counterclockwise until tight, then turn clockwise approximately

2.5 turns until the arrow marks on the two parts of the rotary connector are aligned. Make sure the front

wheels are pointing straight ahead, and fit the assembly onto the column with the hub to column match

marks (made on disassembly) aligned, and engage the spring loaded pin on the column switch housing

with the slot in the rotary connector.

9. Fit a new locking tab washer, followed by the steering wheel nut, and torque tighten to 25 Nm (18.5 lbf.ft).

Bend up the locking tabs to secure.

10. Refer to section WD to refit the airbag module, and verify the system.

Steering Wheel Alignment

Ideally, the steering wheel should align in the straight running position, with the steering rack centralised

and with equal track rod lengths. In practice, a minor compromise to track rod lengths may have to be made.

To arrive at the optimum setting, proceed as follows:

Note that only one splined joint in the steering system allows a choice of position, this being the lower

joint to rack pinion shaft.

1. Set the front wheel alignment to specification with equal track rod lengths (see sub-section CI.2).

Lotus Service Notes Section HG

Page 5

2. Turn the steering to each full lock in turn and set the steering wheel on the column splines such that its

orientation in one full lock position is the nearest possible mirror image of its position at the opposite full

lock.

3. Secure the steering wheel before road testing the car and marking the actual 'straight ahead' position of the

steering wheel which should deviate from the ideal position by less than 5°. Final alignment is achieved

by asymmetric adjustment of the track rods, retaining the overall toe-out setting.

HG.3 - UPPER COlUMN ASSEMBlY

Mirror image

wheel positions

h53

Column lower

Non-airbag steering

mounting bracket

wheel shown

Instrument

pack support

bracket

'Break out' insert

Column support bracket

Turn & flasher switch

Intermediate

column

Trim pad

collapsible

spider

Column lock

assembly

Upper

Chassis

bearing

scuttle

housing

Wiper

beam

Horn button

Trim pad

switch

h49a

Content .. 57 58 59 60 ..