Rear suspension

From GTM Workshop

Contents 1 Build Manual 2 Kit components required 3 Donor parts required 4 Assembly Build Manual Build Sequence Monocoque Front End Rear End Doors Finishing Donor Components Rover Metro Donor Components Rover 220/420 Components Build Sections Battery Beam end covers Bonnet and front spliter mould Boot bootlock and hinges Brake lines Carpets Dashboard cover Doors Engine cover moulding Engine frame Engine and auxiliaries Exhaust Front suspension Gear change Handbrake lever cables and calipers Door panels Trim Headlight covers Heater and pipework Lights Part trim panels option Pedal box and master cylinder Perspex screens rear and side Petrol tank filler neck and cap Pipes and services through the tunnel Radiator ducting and splash moulds to monocoque Radiator mould radiator and pipework Rear suspension Roof panel Seat belts Seats and runners Separate instrument option Setting up the car for the road Soft trimming Spare wheel mould and spare wheel Steering rack and column Throttle pedal Trimming hard panels Windscreen and rear bulkhead screen Windscreen washer bottle pipes and jets Wiper motor and blades Wiring Wiring loom insruments and fuse box 1800 gear change p.g.1 gearbox 1800 engine mountings 5AS alarm units Hydraulic clutch 1800 engine steady Spyder Supplement Top Seatbelt Mounting Hood Boot Engine Compartment Grills Stainless Steel Mesh

The Libra rear suspension is totally unconventional. The rear suspension utilises two trailing wishbones on either side at the rear of the car, these wishbone like the front wishbones are mounted directly via mounting brackets to the monocoque. Standard Metro front hub assemblies are bolted to the trailing wishbones via the standard ball joints at the top and bottom. The bottom ball joint must be the standard Metro bottom ball joint and not the G.T.A. - G.T.I. ball joint.

Special steering arms are bolted to the hubs on the standard locations and these in turn are connected by the standard Metro track rod end via an adjustable link to a special ball joint, which is mounted to the upper trailing wishbone.

Special upside down adjustable spring height coil over shock absorber units mount between the top trailing wishbone and a mounting bracket bolted directly to the monocoque high on the rear panel. THE L.H.S. METRO HUB IS USED ON THE R.H.S. OF THE LIBRA AND THE RH.S HUB ON THE L.H.S.

Kit components required

• 1 x T300 Rear suspension arm top driver’s.
• 1 x T301 Rear suspension arm bottom passenger’s side.
• 1 x T302 Rear suspension arm lower driver’s
• 1 x T303 Rear suspension arm passenger.
• 8 x T304 Rear suspension mounting bracket.
• 8 x T305 Rear suspension mounting bracket spreader.
• 8 x T307 Rear suspension arm bearing.
• 1 x T308 Rear steering arms driver
• 1 x T309 Rear steering arms passenger.
• 2 x T310 Rear suspension steering arm track rod end.
• 2 x T311 rear suspension arm track rod end.
• 2 x T312 Rear suspension arm adjusting link.
• 2 x T313 Rear suspension arm L H T adapter.
• 2 x T314 Rear damper unit.
• 2 x T315 Rear damper spring.
• 2 x T316 Rear damper mounting.
• 2 x T317 Rear bumper mounting plate
• 1 x T318 Rear suspension, Nut and bolt pack.
• 4 x T319 Rear suspension Rod end lock nut.
• 8 x T320 Rear suspension Rod end adjuster

Donor parts required

Two front hub assemblies (solid discs) complete with top ball joint & bottom swivels (not G.T.I. ).

Assembly

The rear suspension of the Libra mounts directly to the monocoque. By referring to the rear suspension drawing it is impossible to identify the mounting holes for the rear suspension mounting brackets T304. These holes are indicated on the monocoque by small indentations Drill the centre of these indentations with a 0.125" drill. Open out the holes to 6-mm clearance. Loosely mount the 8 rear suspension mounting brackets to the monocoque using the six millimetre socket cap head screws 35 millimetre long, spare 40 millimetre long screws are provided for areas where the glass fibre thickness is too great to allow a nyloc nut to fit satisfactorily. Use the shortest screws possible in all applications.

The rear suspension mounting brackets have no spaces between them and the monocoque as the adjustment is obtained by adjusting the screw threads from the bearings in to the wishbone. Inside the monocoque there are spreader plates. Note the outside bottom mounting bracket is mounted upside-down compared to the other brackets, i.e. the rear suspension arm Bearing is inserted from the bottom.

Assemble the rear suspension arm bearings T307 into the wishbone. On both wishbones the inner bearings screw directly into the wishbone. Locking nuts T309 are used to lock the bearing in the correct position when assembled to the wishbone. Adjust the inner bearings so that the centre of the ball is 39 millimetres from the face of the threaded tube that holds the bearing. Lock the bearing with the lock nut in this position. The outer track rod ends are located to their housing tubes using 2 adjuster nuts T320. These nuts allowed the wishbone to be adjusted when assembled to the car without the removal of the bearing frown its housing. In a similar manner to the inner bearings adjust the centre of the ball to 39 millimeters from outside face of the housing. This will be adjusted finally when the car is prepared for the road.

The wishbones can now be assembled to their mounting brackets using the special nyloc nuts and washers provided. Note the unusual pitch of these nuts Tighten the tapers securely into the mounting brackets. Once you or satisfied everything is correct tighten the six millimetre nyloc nuts that hold the mounting brackets to the monocoque.

Now fit the top damper mounting brackets T316 to the tub. The mounting holes are indicated on the monocoque by small indentations. Drill the center of the indentations with a small drill, and then drill out these holes to 6mm clearance holes. Mount the brackets with the 6-millimeter, by 35 millimeter long, socket cap bolts. There are no packers between the mounting and the monocoque, there is a spreader plate T317 on inside of the monocoque.

The rear damper T314 and the springs can now be fitted between the top wishbone and the mounting bracket. Use the 12-milimeter by 60 millimetres long bolt at the top and the 12-millimeter by 50-millimeter long bolts at the bottom.

The standard Rover Metro hub assembly can be mounted to the wishbone using the standard top and bottom swivels. The bottom swivel is mounted to the top face of the bottom wishbone using the 8-millimeter by 25-millimeter long socket cap bolts.

The Libra steering arms T308 replace the standard Rover Metro steering arms, T309. These arms are attached to the hub assembly by the 10-milimeter by 35- millimeter long bolts.

Note the standard Rover Metro location sleeves of retained. Build up the rear track rods by first fully screwing in the left-hand thread adapter T313 to the track rod end T310. This adapter should be securely screwed in to the track rod end preferably with some form of a lock tight. Screw the left-hand threaded half nut to the left and threaded adapter followed by the adjusting link (Approx. - Ball center to center is 330 mm) T312. Screw the 14- millimeter half nut on to the track rod end T311 and then the track rod end into the adjusting a link. This assembly can now be fitted to the rear suspension taking care to make sure that the tapers are well seated. Adjust the adjusting link to give an approximate straight-ahead position of the hub, which will of course be adjusted more accurately on the setup for the road.