Updated 22 nd May 2018

Transcription

1 REAR SUSPENSION SECTION DV Sub-Section Page General Description & Service Schedule Inspection DV.1 3 Geometry & Adjustments DV.2 4 Wishbone Pivot Bushes & Spherical Joints DV.3 8 Anti-Roll Bar (ARB) DV.4 9 Hub Unit & Hub Carrier DV.5 11 Spring & Damper Assembly DV.6 13 Upper & Lower Wishbone Assemblies DV.7 14 Adjustable Suspension Option DV.8 18 Updated 22 nd May 2018 Page 1

2 Rear Suspension Layout Non-adjustable suspension layout shown Spherical joint Spring/damper unit Top wishbone Damper top mounting bracket Calliper mounting ARB Turnbuckle lug drop link Lower wishbone Toe control link Hub unit Anti-roll bar ARB chassis mounting bush Hub carrier d51 Updated 21 st May 2018 Page 2

3 DV.1 - GENERAL DESCRIPTION AND SERVICE SCHEDULE INSPECTION The independent rear suspension comprises, on each side of the car, upper and lower forged aluminium wishbones, a forged steel toe control link, a concentric coil spring/telescopic damper unit and a tubular steel anti-roll bar, all being attached to the galvanised steel rear subframe. A forged steel hub carrier, provides a mounting for the hub bearing unit to which the 5-bolt road wheel and brake disc are attached and also carries bosses for the cross-axis fixing bolts for the brake calliper. Lower wishbone assembly The primary, vehicle weight bearing, lower wishbone, is widely based and substantially cross braced and incorporates separate double shear mounting points for the hub carrier and damper lower eye and a single lug for the anti-roll bar drop link. The outboard end of the wishbone is through bolted to a spherical joint pressed into the lower eye of the hub carrier. Upper wishbone assembly The upper wishbone is of simple 'A' form, and houses a replaceable through-bolted spherical joint at its outboard end to connect to the hub carrier. Inboard wishbone bushes The inboard ends of both upper and lower wishbones use replaceable bonded rubber pivot bushes for maintenance free articulation, with the bush compliance profile tuned to provide the vehicle with accurate and responsive dynamic characteristics. Toe control link assembly The toe control link is a two part steel forging incorporating an adjustment turnbuckle, and by connecting a rearward extension on the hub carrier to the chassis subframe, a 'toe-in on compression' bump steer characteristic is produced. Through bolted spherical joints are used in each end of the link and the threaded turnbuckle allows for adjustment of rear wheel alignment. An eccentric cam incorporated at the rear pivot point for the lower wishbone, provides a means of camber adjustment. Non-Adjustable damper options The standard factory suspension damper is referred to as the Tour option. An optimised Sports suspension is available with the thicknesses of selected internal shims fitted to the Sports damper are altered to change the rebound and compression characteristics. Both options use a Bilstein monotube telescopic damper, the bottom of the damper fixes to the lower wishbone in a double shear arrangement, with the damper top end secured to the subframe via a steel bracket bolted inside the subframe tower. The damper uses a rubber bush in the top eye for noise suppression and a through bolted spherical steel joint in the lower eye for optimum dynamic response and is orientated with the damper rod uppermost. Non-Adjustable damper option springs Both options use the same dual rate, concentric coil spring which abuts against a lower seat fixed to the damper body and an upper seat secured to the damper top eye which is also bolted to the subframe, thus relieving the damper top bush of vehicle weight to the benefit of noise and ride refinement. The close coiled end of the spring is mounted lowermost, on the damper body. Anti-Roll bar A tubular steel anti-roll bar is mounted in rubber bushes to the underside of the subframe rearward of the axle line and curves over each toe-link before connecting to the lower wishbone rear leg via a short ball jointed drop link. Hub bearings The hub bearing unit, which is common to all four wheels, is fixed to the hub carrier by 4 bolts, and incorporates a wide spaced double row ball bearing and a vehicle speed sensor ring integrated into the inboard seal, whose 48 pole signal is picked up by a sensor mounted in the rear of the hub carrier. This data is used for the anti-lock brake, vehicle stability, engine management and speedometer functions. Updated 21 st May 2018 Page 3

4 Öhlins TTX 2-Way adjustable damper option Referred to as the 'Race' suspension option which is available for the GT model range, these dampers are an oil filled, gas pressurised twin tube configuration. The ride height and the Rebound & Compression settings are adjustable; refer to sub-section DV.8 for further information. SERVICE SCHEDULE INSPECTION The Service Schedule specifies that the security of the front and rear suspension is checked at each service. For cars used on race tracks, or in similar conditions, suspension components and torque checks should be carried out between sessions. This operation requires that all the principal suspension pivot bolts are torque checked, noting the following points: Where a bolt is tapped into a housing or weldnut, and relies on a thread locking compound for security, it is important to appreciate that if the bolt is disturbed, the locking compound must be re-applied. The following procedure should be adopted for all such fixings: - Check the torque of the fixing. - If the specified torque is attained without the fixing being disturbed (moving), take no further action. - If the bolt moves, the locking action of the thread adhesive will have been compromised. Remove the bolt completely, clean off all old adhesive using a wire brush and acetone, and apply new adhesive as specified. - Refit the bolt and tighten to the specified torque. - If for any reason a bolt is found to have become loose, and the car has been operated for any period in this condition, the bolt should be renewed as a standard precaution and related components carefully inspected for hole ovality, undue stress or wear. Updated 21 st May 2018 Page 4

5 DV.2 - GEOMETRY & ADJUSTMENTS Provision is made for the adjustment of wheel alignment and camber. Under normal service conditions, no periodic scheduled check of the geometry is necessary, with a full geometry check required only after suspension repair, or if excessive tyre wear is evident, or handling deficiencies encountered. Before any measurements or adjustments are made, it is essential first to set the vehicle to its mid laden ride height, approximating to driver and passenger and a half/full tank of fuel. This will require the vehicle to be ballasted or tied down: Chassis Ride Height Points Ride height to be measured from the ground up to the machined tooling holes located in the chassis siderails (highlighted and shaded in yellow). A B c59 Preparation for Geometry Inspection Measurements should be taken from mid-laden ride height (Equivalent of 2 x 75 kg occupants + full fuel tank) Set car to front and rear ride heights and tyre pressures applicable to the Evora model; refer to Service Notes section TDA - Vehicle Technical Data, for rear suspension setting information. Suspension geometry settings Please refer to Service Notes section TDA - Vehicle Technical Data, for rear suspension setting information. Alignment Wheel alignment refers to the parallelism of the wheels when viewed from above and is crucial to vehicle stability, handling and tyre wear. Difference between rim measurements = overall toe in Individual toe in angle FRONT c26 It is measured either by the angle a wheel makes with the vehicle centre line, or the difference in dimension between the wheel rim to wheel rim measurement at the front and rear of the wheel at hub centre height. The wheels are said to 'toe-in' when the wheel paths converge ahead of the vehicle, and 'toe-out' when they diverge. Rear wheel alignment should be measured only using equipment which measures individual rear wheel alignment relative to the car centreline. Wheel alignment is designed to vary with suspension travel ('bump steer') and the base setting should be measured only at the specified mid laden ride height. Updated 21 st May 2018 Page 5

6 Rear Wheel Alignment This is controlled by toe control link assemblies (2), each fitted to the LH and RH suspension between the rear subframe and rear hub carriers. Adjustments are by altering the overall length of both toe control links which is achieved by rotating the turnbuckle at the centre of the assembly. Toe control link outer joint fitted to rear hub carrier Outer RH threaded lock nut Inner LH threaded lock nut Toe control link inner joint mounted in rear subframe channel Lower wishbone Turnbuckle d72 Alignment Adjustment Preparation: Ensure the vehicle is at mid-laden ride height, see previous page for information. 1. Slacken both locknuts, and turn the buckle as necessary to increase or decrease the effective length of the link. Note: As a guide, lengthening the link rod by a turn of one 'flat' (one sixth of a turn) will increase toe-in by approximately 1.6 mm. 2. After adjustment, hold each section of the toe-link in turn using the flats provided, whilst tightening each of the two locknuts to 45 Nm and ensure that the axes of the toe-link pivot bearings are parallel. Updated 21 st May 2018 Page 6

7 Toe control link to rear hub carrier nut and bolt fixing Toe control link to rear subframe channel nut and bolt fixing Toe control link assembly LH threaded link joint fitted inboard 'subframe' side of vehicle. d73 Toe Control Link Assembly Removal (LH side described, RH similar): 1. Remove the rear undertray/diffuser assembly, see service notes section AA.3 for further information. 2. Remove the LHR road wheel; see Service Notes section GT.4 for further information. 3. Release the M14 torque nut and M14 x 90 bolt securing the outer toe control link joint to the hub carrier, withdraw the bolt from the hub carrier and outer link spherical joint. 4. Release the M14 torque nut from its M14 x 75 bolt securing the inner toe link joint to the subframe, remove the bolt from the subframe and inner link spherical joint. 5. Withdraw the toe control link assembly from the rear subframe and suspension upright assembly. Refitment: As per removal except: - Ensure that the LH threaded link joint of the toe control arm is fitted inboard of the rear subframe. - Refit the inner and outer link joints bolts in the correct orientation (bolt head facing rearwards of the vehicle). - Discard the previously removed torque nuts and fit new nuts - Ensure that the axis of the toe-link pivot joints are parallel, see note below - Tighten both inner and outer M14 fixings to 135Nm. - If renewing toe control link assembly it will be necessary to perform a geometry check and adjustment (as required as shown on previous pages) using the vehicle mid-laden ride height figures and geometry settings as shown in Service Notes section TDA. Updated 21 st May 2018 Page 7

8 Camber Adjustment Camber is the angle from vertical of the wheel as viewed from the rear, and is said to be negative when the wheel leans inwards at the top (and positive when leaning outwards). The primary purpose of camber is to achieve the maximum efficiency of the tyre under cornering loads and body roll, with the specification closely allied to a particular wheel/tyre combination. The camber angle changes with suspension travel, becoming more negative on bump, and should be measured only at the specified ride height; refer to sub-section DV.2 for further information. Incorrect camber can result in handling deficiencies and excessive tyre wear. Vertical Camber angle Wheel centreline Toe control link bolt REAR VIEW OF SUBFRAME Rotation of rear pivot bolt Guide plate Eccentric Camplate Corresponding movement of wishbone d59 Rear Pivot Bolt Nut C53 Rear Pivot Bolt/Camber Adjustment An eccentric cam at the rear inboard pivot of each lower wishbone provides a means of camber adjustment. The pivot bolt is inserted from the front, with the bolt head featuring an integral eccentric cam, and with a corresponding eccentric camplate clamped beneath the nut on the front side of the rear pivot. The camplate is keyed to the bolt via a tongue and groove feature to ensure alignment between the two cams. Each cam is constrained by vertical guides in a riveted insert in the subframe, whereas the pivot bolt hole in the subframe is slotted horizontally. Thus by turning the bolt (and eccentric cams) the wishbone pivot axis may be moved inboard or outboard. After adjusting camber ensure that the pivot bolts are tightened to 86 Nm. Be aware that any camber adjustment will also affect wheel alignment, which must subsequently be checked and/or reset. If it is neccessary to remove or renew the rear pivot bolt then ensure that upon refitment that the arrow displayed on the eccentric cam of the pivot bolt is pointing vertically downwards. Only tighten the rear pivot bolts with the wishbones in their 'Ride height' positions, see first page of this subsection for further information. Page 8

9 Lotus Service Notes DV.3 - WISHBONE PIVOT BUSHES & SPHERICAL JOINTS Pivot Bushes The upper and lower wishbone pivot bushes are bonded rubber type with a plastic flanged outer sleeve, an alloy inner sleeve and an aluminium interleaf sleeve within the rubber bush to control the flexing characteristic. The rubber material specification has been selected to optimise the handling/refinement balance. The flanged end of the bush incorporates a snubbing feature to limit the axial distortion of the bush, with each bush arranged to resist braking forces transmitted through the suspension; Both top wishbone bushes are inserted from the front and both bottom wishbone bushes from the rear. A chamfer is provided in the wishbone bore for this purpose. The bushes may be pressed out of the wishbone eyes, and new bushes fitted using suitable press tool dollies. Smear the outer surface of the new bush with IPC 'P-80' rubber lubricant emulsion to ease fitment. Inter Leaf Rubber c51 Outer Insert Inner Insert d69 Spherical Joints Through bolted spherical joints are used at the outboard ends of the upper and lower wishbones, for the lower wishbone the joint is pressed into the hub carrier, for the upper wishbone its pressed into the wishbone itself. Both ends of the toe control links and the lower eye of the dampers are also articulated with spherical joints but service replacements are only available for the wishbones The joint consists of 4 main components, 1.A hollow steel inner tube to accommodate the through bolt, the tube also incorporates a central spherical section which, 2.The spherical section is completely retained within concave polymide bushing allowing the tube to rotate 360º within its own axis inside the bushing, whilst also allowing it a small degree of radial tilt (up to 14º). 3. Dust seals are fitted either side of the assembly around the inner tube and outer sleeve to prevent the ingress of debris into the joint that may cause its premature wear 4. The polymide bushing and inner tube is contained within an outer metal sleeve allowing the whole assembly to be pressed into the hub carrier/lower damper mounting. Page 9

10 DV.4 - ANTI-ROLL BAR (ARB) A tubular steel anti-roll bar is mounted beneath the rear subframe behind the axle line in rubber bushes retained by extruded alloy clamps. One clamp secures the bar at each side to the bottom surface of the subframe longerons via two bolts tapping into a steel nutplate located to the inside the longerons. Each end of the bar curves over the toecontrol link before connecting to a machined hole in the lower wishbone rear leg via a short ball jointed drop link. A pair of washers crimped to the bar, bear against the outboard sides of the mounting bushes to provide lateral location of the bar. Drop link Torque nuts Anti-roll bar bush & bracket Anti-roll bar A heatshield wrap consisting of a one piece fibreglass sleeve with an outer laminated aluminium foil is fitted around the roll bar in between the mounting clamp area to insulate the bar and bushes from heat produced by the engine and exhaust system. The drop link ball joints require no maintenance and are replaceable only as part of the handed drop link assembly. Removal: 1. Remove the rear undertray, see Service Notes section AA Release the M10 x 20 screws (4) (torque 45Nm) securing the 2 ARB bar clamps and bushes to the rear subframe nut plates. 3. Remove screws and withdraw the clamps and bushes from the ARB. 4. Release the M12 torque nuts (2) (torque 36Nm) securing the ARB to the drop link upper joint on the LH & RH side (a 5mm hexagonal socket is provided in the end of each ball pin stud to aid this process) and withdraw the ARB. Refitment: The same as removal except: - Castrol LMX rubber grease, or equivalent, should be used when fitting the rubber bushes onto the ARB. - Ensure the ARB bush is fitted back onto the bar with manufacturers split orientated towards the rear of the vehicle. - Renew the ARB drop link ball pin self torque nuts. Note if the roll bar is being renewed then inspect the condition of the heatshield sleeve, transfer to the new bar or renew as required. Page 10

11 Anti-roll bar bush If fitting a new anti-roll bar or bush then ensure that the bush is fitted in the correct orientation with the manufactured split in the bush facing downwards and rearwards of the vehicle. Anti-roll bar bush This will reduce bush and bar wear by ensuring that any water and debris that is thrown up from the road into the path of the bushes can drain away instead of collecting in the bushes clamping split with the subsequent rotational movement of the bar causing both the bar and bush to wear. Ensure split in bush is orientated rearwards and downwards Anti-roll bar bracket Page 11

12 Lotus Service Notes DV.5 - HUB UNIT AND HUB CARRIER Hub Unit The unit is non serviceable and any malfunction that results in the failure of any of its functionality will require the renewal of the assembly. Hub assembly fixing screws Disc retaining screws Wheel speed sensor & fixing Driveshaft hub nut Hub assembly Removal: This operation will require the vehicle to be placed on a wheel free lift and with the rear wheel(s) removed as required, see Service Notes sections AA.1 and GT.4 for further information. 1.With the parking and footbrakes firmly applied, remove the driveshaft nut as required (both RH thread) see service notes section FR.5. for further information. 2.Release the two bolts securing the brake calliper as required to the hub carrier and support the calliper aside without straining the brake hose see service notes section JP.5 for further information. 3.Check that the parking brake is released, back off the brake shoe adjuster, release the M8 x 12 skt cap head screws (1) securing the brake disc/drum to the hub and remove, see service notes section JP.7. 4.Release the harness connector from the wheel speed sensor, release the harness from any suspension components, and secure the harness aside. Then release the single M5 x 12 screw securing the wheel speed sensor, and withdraw the sensor from the hub carrier. 5.Release the M10 x 33 (4) socket headed hub to carrier screws, then withdraw the hub unit from the hub carrier and driveshaft. Refitment: Reverse procedure of renewal except: - Apply a light film of Permabond A130 to the threads of the hub to carrier screws before refitting and tightening to 70Nm. - Apply a light coating of Mobiltemp 1 high temperature grease to the wheel speed sensor as shown in the illustration and tighten screw to 5Nm. - Adjust the parking brake shoes and pump the brake pedal to reposition the pads before driving the car. Shaded area with Permabond to hub carrier screw Shaded area with high temperature grease Page 12

13 Hub Carrier If removing as part of the strip down and refitment of the complete suspension assembly then the hub carrier and hub unit can be removed as a complete assembly, refer to previous instructions for hub unit removal, steps 1-4 to prepare hub carrier for removal. Upper wishbone to carrier mounting point Outer toe control link to carrier mounting point Lower wishbone to carrier mounting point 1. Release the M14 torque nut and M14 x 90 bolt securing the outer toe control link joint to the hub carrier, withdraw the bolt from the hub carrier and outer link spherical joint, refer to sub-section DV2 for further information. 2. Release and remove the M14 x 100 bolt and M14 torque nut securing the upper wishbone spherical joint to the hub carrier (135Nm). 3. Release and remove the M14 x 125 bolt and M14 torque nut securing the lower wishbone to the spherical joint on the hub carrier (135Nm). 4. Separate the toe control link, upper and lower wishbones from the carrier, then slide the carrier and hub unit off of the driveshaft splines. Refitment: Is the reverse of removal except - Discard the previously removed torque nuts and fit new nuts. - Ensure the upper and lower wishbone bolts are fitted in the correct orientation, head of upper bolt facing towards the rear of the vehicle and the head of the lower bolt facing towards the front of the vehicle. Page 13

14 DV.6 - SPRING AND DAMPER ASSEMBLY Refer to sub-section DV.8 for vehicles fitted with the Ohlins Race suspension option. Note: The upper damper bolt passing through the upper spring/damper mounting retains the road spring in compression, therefore the spring/damper/top mounting bracket should be removed from the car as a complete assembly. Removal: 1. Raise and support vehicle, see service notes section AA.1 for further information. 2. Remove the appropriate road wheel, see Service Notes section GT.4 for further information. 3. Remove the M8 x 20 screws (2) securing the upper section of the top mounting bracket to the to the inside of the subframe tower (24Nm) and the M10 x 20 screw (1) securing the side section of the top mounting bracket to the front face of the tower (45Nm). Braking components not illustrated for clarity Top mount bracket upper section retaining screws/nuts Top mount bracket side section retaining screw location 4. Remove the M14 x 105 bolt and M14 torque nut (1) securing the lower end of the damper to the bottom wishbone mounting point (135Nm). Pull the assembly outwards so that the base of the damper clears the lower wishbone then withdraw the assembly from the vehicle, collect the spacer washers (2) fitted between either side of the lower damper bush and wishbone mounting point. Refitment: Is the reverse of removal except: - Renew the lower damper to wishbone clevis bracket self torque nut. Separating the spring damper assembly: - Using spring compressor clamps and taking all suitable safety precautions relieve tension from the upper spring seat and mounting. - Remove the M12 x 70 bolt and M12 torque nut (1) securing the upper end of the damper to the mounting bracket (86Nm). - The spring/damper mounting and upper spring seat and spring can be pulled away from the damper. Lower mounting nut/bolt Head of bolt positioned to the 'Long leg' section of the bracket Spring Damper Damper bolt/nut Mounting bracket Upper spring seat d80 Refitment: Is the reverse of removal except: Care point: Ensure that the upper damper mounting bolt is orientated so that the head of the bolt is fitted to the Long leg of the mounting bracket. d81 Updated 21 st May 2018 Page 14

15 DV.7 - UPPER AND LOWER WISHBONE ASSEMBLIES Upper Wishbone Spring/Damper assembly not illustrated for clarity Upper wishbone pivot bolts and nuts Upper wishbone d82 Removal: 1. Raise and support vehicle, see Service Notes section AA.1 for further information. 2. Remove the appropriate road wheel(s), see Service Notes section GT.4 for further information. 3. Remove the rearmost section of the wheelarch liner(s) as required; see Service Notes section BD.17 for further information. 4. Release and remove the M14 x 100 bolt and M14 torque nut securing the upper wishbone spherical joint to the hub carrier, refer to sub-section DV.5 for further information. 5. Release and remove the M12 x 85 pivot bolts and M12 nuts (2) securing the upper wishbone to its mounting channels in the rear subframe, (torque 90Nm). Care point: The forward most pivot bolt nut may be partially obscured by the spring/damper assembly. It may be necessary to partially remove the spring damper assembly to gain access to the pivot nut to achieve satisfactory removal and torque tightening, refer to sub-section DV.6 for further information. 6. Withdraw the wishbone from the subframe. Refitment: Is the reverse of removal except: - Only torque tighten the pivot bolts once the vehicle/wishbones are in the ride height position, refer to subsection DV.2 for further information. - Refer to sub-section DV.3 if replacing the wishbone pivot bushes. Page 15

16 Lower Wishbone Lower wishbone WSS 'P' clip and retaining screw Hanbrake cable retaining cable tie Retaining nut and eccentric washer Rearmost wishbone pivot cambolt Forward most wishbone pivot bolt and nut d83 1. Raise and support vehicle, see Service Notes section AA.1 for further information. 2. Remove the appropriate road wheel(s), see Service Notes section GT.4 for further information. 3. Cut and discard the cable tie securing the handbrake cable to inner span section of the wishbone assembly. 4. Release and remove the Wheel Speed Sensor (WSS) harness retaining M6 x 16 'P' clip screws (2) securing the sensor harness to the upper side of the wishbone (torque 9Nm). 5. Release the M14 torque nut and M14 x 90 bolt securing the outer toe control link joint to the hub carrier, withdraw the bolt from the hub carrier and outer link spherical joint, refer to sub-section DV.2 for further information. 6. Release the M12 torque nut securing ARB drop link lower joint to the lower wishbone, refer to sub-section DV.4 for further information. 7. Remove the M14 x 105 bolt and M14 torque nut (1) securing the lower end of the damper to the bottom wishbone mounting point. Pull the assembly outwards so that the base of the damper clears the lower wishbone and collect the spacer washers (2) fitted between either side of the lower damper bush and wishbone mounting point, refer to sub-section DV.6 for further information. 8. Release and remove the M14 x 125 bolt and M14 torque nut securing the lower wishbone to the spherical joint on the hub carrier (135Nm), refer to sub-section DV.5 for further information. 9. To aid re-assembly, match mark the eccentric cambolt adjuster position at the rearmost inner wishbone pivot mounting point. Page 16

17 10. Once marked, release and remove the M12 nut and M12 x 95 cambolt (1) securing the rearmost lower wishbone pivot to the subframe ensuring to collect the eccentric cam adjusters fitted behind the M12 nut, (torque 86Nm). 11. Release and remove the M12 nut and M12 x 85 bolt (1) securing the forward most lower wishbone pivot point to the subframe (torque 90Nm). 12. Withdraw the lower wishbone from the subframe. Refitment: Is the reverse of removal except: - Only torque tighten the pivot bolts once the vehicle/wishbones are in the ride height position; refer to subsection DV.2 for further information. - Secure the handbrake cable to the inner span of the wishbone using a new cable tie. - Perform a rear suspension geometry inspection and adjustment, refer to sub-section DV.2 for further information. - Refer to sub-section DV.3 if replacing the wishbone pivot bushes. Page 17

18 DV.8 - ADJUSTABLE SUSPENSION OPTION Öhlins TTX 2-Way Adjustable Dampers Fitted as standard to both GT430 and GT430 Sport models and optional on the GT410 model, these dampers are an oil filled, gas pressurized twin tube configuration with the ride height and the rebound & compression settings being adjustable Further information is contained within the Öhlins Automotive Manual which can be downloaded at: (A) Damper Seals Bushes are not used on the Ohlins damper assemblies, instead felt seals are fitted inside the mounting eye apertures, stepped spacers (see below) are then fitted over the seals to prevent the ingress of dirt/water etc that could otherwise enter between the mounting eye apertures and mounting bolts which could result in noise, vibration and wearing of both the bolts and mounting eyes. (B) Damper mounting spacers To compensate for the smaller dimensions in thickness as compared to the Bilstein damper mounting points as well as to ensure that the damper bodies do not contact the driveshafts (because of the increase in damper body diameter), the damper/ spring assemblies are positioned slightly offset (forward) as compared to the Bilstein damper options. This is achieved by using different length stepped spacers (also see above), fitted between either side of the lower damper bush and wishbone mounting points and, (using a modified top mounting bracket), between the upper damper bush and the top mounting bracket. C2 C3 C4 A B1 The upper spacers (B1) are fitted with the shorter (11.5mm) spacer fitted forward most and the longer (21.5mm) spacer fitted rearward of the upper damper mounting bush. The stepped ends of both upper spaces contact the felt sealing rings. For the lower spacers (B2), the opposite end of the machined step is conical, the conical end must be fitted outboard so it contacts the lower wishbone mounting points. The shorter (13.5mm) spacer must be fitted forward most and the longer (23.5mm) spacer fitted rearward of the lower damper mounting bush. (C) Springs Rear damper assemblies are fitted with 2 springs, the main road spring (C1), fitted lowermost which abuts against the lower/adjustable spring platform and a smaller helper spring (C2), positioned above the road spring, separated by a spacer (C3). The top of the helper spring abuts against the underside of the damper top mount (C4). The helper spring ensures that the base of the road spring maintains its correct positioning and contact with the spring platform (C5), even when the damper travel is at its fullest extent. (D) Rebound & Compression Adjusters Identification The rebound adjuster knob (D1), is black in colour and labelled REB, the compression knob (D2), is gold in colour and labelled COMP. Because the same part number rear damper/spring assembly is used on both rear sides of the vehicle, therefore the inboard/outboard positioning of the rebound and compression knobs will change (be opposite) dependant upon left or right hand fitment. C1 C5 D1 D2 B2 Inspection & Cleaning Front of vehicle At every service the spring platform adjusters should be cleaned, inspected and lubricated and the lock ring security should also be checked. Servicing IMPORTANT: The Öhlins damper assemblies must be regularly serviced. This must be performed by an Öhlins approved service centre every 11,000 miles (18,000km) or 24 months (for road use vehicles, whichever is the soonest), please contact Öhlins directly for track use recommendations. Failure to adhere to the inspection and maintenance recommendations as set out by Öhlins may invalidate the warranty on the damper assemblies. Updated 22 nd May 2018 Page 18

19 Lotus Service Notes Grub screw Grub screw ohe237 ohe238 Ride Height Adjustment It is recommended to remove the road wheels to gain access to the retaining rings; refer to service notes sections AA.1 and GT.4 for further information. Height adjustment is made by loosening (but not removing) the grub screw located in the spring platform retaining ring, then using a C spanner, wind the spring platform up or down, clockwise to increase the spring preload or counter-clockwise to decrease preload. Tighten the grub screw once the required ride height is achieved. Compressing the spring will raise the ride height; releasing compression from the spring will lower the ride height. Refer to service notes section TDA for suspension ride height details. Page 19 Updated 21st May 2018

20 Lotus Service Notes Rebound & Compression Adjustment Hard Hard Soft Soft ohe235 ohs236 ohe238 Rebound Adjustment Adjust by turning the black adjuster knob labelled REB, or, use a 14 mm socket and T-bar and turn the hexagon nut within the adjuster knob. Turn clockwise to increase damping or turn counter-clockwise to decrease. Compression Adjustment Adjust by turning the gold adjuster knob labelled COMP, or, use a 14 mm socket T-bar and turn the hexagon nut within the adjuster knob. Turn clockwise to increase damping, turn counter-clockwise to decrease. Adjuster Resetting To set to factory specificationsturn the required adjuster clockwise to the fully closed position until it stops. Turn counter clockwise to open and count the clicks until you reach the number of clicks required. For both the rebound and compression settings refer to service notes section TDA Rear suspension for further information. Page 20 Updated 21st May 2018

21 Removal: Refer to sub-section DV.6 steps 1-4 for vehicles fitted with the Bilstein 'Tour' or Sport suspension options for information on removing the spring/damper assembly. Step A Step 3 from sub-section DV.6 Spacer D Step 3 from sub-section DV.6 Stepped end Spacer C Refitment: Is the reverse of removal shown in sub-section DV.6 except: Refit the damper/spring assembly into position ensuring the conical ends of lower spacers are fitted outboard so that the conical ends contact the lower wishbone mounting points. The shorter (13.5mm) spacer (A) must be fitted forward most and the longer (23.5mm) spacer (B) fitted rearward of the lower damper mounting bush. Note 3 Note 1; Fit the lower mounting bolt through the front of the lower wishbone so that the bolt head is pointing towards the front of the vehicle, If it is fitted the other way as part of a complete suspension rebuild and future disassembly is required, the bolt may foul against the rear control toe link if trying to be withdrawn from the rear wishbone. Renew the lower damper to wishbone clevis bracket self torque nut (torque 135 Nm). Spacer B Separating the spring damper assembly: A. Remove the M14 x 75 bolt and M14 torque nut securing the upper end of the damper to the mounting bracket (torque 135Nm). Spacer A B. The mounting bracket and spring/damper assembly can now be separated. Refitment: Is the reverse of removal: Note 1 Step 4 from subsection DV.6 Ensure the upper spacers are fitted with the shorter (11.5mm) spacer (C) fitted forward most and the longer (21.5mm) spacer (D) fitted rearward of the upper damper mounting bush. The stepped section of both upper spacers must be orientated inwards so that it contacts the felt sealing ring within the eyebolt aperture to prevent the ingress of dirt/water etc which could cause premature wear of the damper eye bolt apertures. Note 2: Ensure that the upper damper mounting bolt is orientated so that the head of the bolt is fitted to the forward side of the mounting bracket (torque 135 Nm). Note 3: If fitting a new assembly initially adjust the distance between the top of the damper body to the underside of the spring platform to 65 mm as a base setting, then adjust the final ride height as previously described in this sub-section, refer to service notes section TDA for both ride height and compression and rebound setting information. Updated 22 nd May 2018 Page 21