Connect the
lower joints.

Paired inner bush comparisons and hollow arm eyes now lead to a forked outer joint, a separate bored kingpin foot, stepped lower pin, cotter and end closures. The wishbone plan, inner pivot centerlines and neighboring running-gear positions remain drawing references.

Inspect the interfaces

A meaningful size correction with a limited source

Factory PDF p. 141 lists four 2A4272 inner fulcrum pins, eight 8G621 lower-link bushes and four 2A4024 special washers/nuts. Two bushes now meet at each inner eye; the old model had one filled cylinder at each pivot. Those old bush and pin envelopes were about 79.59 mm and 30.48 mm in diameter respectively, derived from arbitrary body drawing units.

The supplier’s A486/8G621 stock description lists a 23–25 mm tapered outside diameter and 12.5 mm bore. These radial values guide a replacement comparison, not a measurement or identification of this car’s fitted bushes. The same listing gives 28 mm and 17 mm axial lengths without section datums sufficient for this assembly. Both readings are retained in metadata without being applied as a fitted stack. Its metal-insert construction is not reconstructed.

MGOC’s own suspension listing identifies the GHF223 retaining nut as 3/8 UNF; the pin’s terminal envelope uses the corresponding 9.525 mm nominal diameter without threads. The 12 mm shoulder, head, length, washer shape and nut profile remain estimates; the thread designation does not establish any of those dimensions.

Outer fulcrum and kingpin foot

The earlier shared-front factory drawing, p. 139 separates the lower link, 2A4020 fulcrum pin, kingpin foot, 51K1769 standard cotter, 51K3424 small-end blanking plug, 8G589 screwed large-end plug, UHN400 nipple and 2A4205/2A4206 rings. Its 51K2751 oversize cotter is a distinct alternative, not selected here. This earlier illustration supplies topology, not a 1975 fitted-parts identification. MGOC’s current Midget listing corroborates the lower-pin and different end-plug roles.

Two bored arm ends replace each filled outer cylinder. An estimated central fork opening receives the bored kingpin foot; the separate stepped pin crosses both. The cotter has its own transverse hole beside a simplified pin flat. Different small- and large-end closures and two ring envelopes make the lower-joint relationships inspectable. The kingpin shaft keeps the prior inclination, upper station and 18.63 mm radius. It is removed from the legacy swivel-axle group, leaving spindle, wheel, brake and steering datums unchanged.

Both axes remain at X magnitude .58, Y=.27, Z=1.20 in body drawing units, along Z. No new owner dimensions are applied. The separate kingpin/carrier study now replaces the solid carrier and upper joint with bored sections, independent bushes, dust tubes, thrust and an offset trunnion. Real reamed fits, shaft sections, shim stack and end float remain unverified. An estimated reduced upper terminal is added above the retained shaft-top datum. The anti-roll study corrects the former horizontal fixing pattern to the forward wall using IMG_6914 and the factory flat-plate arrangement. The old unsupported fixing in this fork gap is superseded. Six new reference bores and an estimated 40 mm-deep forward wall establish the constructed relationship; fitted coordinates, depth and drilling pattern remain unverified.

Declared local construction

Each tapered body is drawn 19 mm long with a 3 mm external lip and an estimated 29 mm lip diameter. These axial/lip dimensions are construction choices. Hollow arm eyes follow the comparison taper with a small display allowance, without modeling pressed rubber, bonded inserts or measured compression. The pan keeps its old plan and top station, with an estimated 2.54 mm plate/lip instead of a filled slab. Its former solid outer sleeve is now separated as described below.

The matching body reference now uses 16.5 mm-radius eye pockets, 6.25 mm-radius ear bores and ear offsets of ±.030 body units, replacing the previous bush-sized primitive pockets and ±.059 offsets. Pivot centers remain X magnitude .36, Y=.27, Z=.98/1.42. This changes a declared local construction around the new bush comparison; it does not identify actual body cutouts, pressed fits, pin engagement or loaded axial contacts. Eleven other front-structure mesh records are retained exactly.

Workshop and travel boundaries

Arm, inner bushes, kingpin, pins, cotter and end closures have separate inspection translations. The kingpin and carrier share a display offset only; that does not prove retained ownership during service. These do not release spring load, prove pin extraction or articulate a suspension joint. No safe support state, sequence, torque, alignment, available tool room or verified removal path is supplied. Retain the spring, frame, anti-roll bracket and surrounding components when identifying the chain; their common registration is still estimated.

Actual outer thread engagement, cotter taper/clocking and the upper trunnion remain unresolved. MGOC describes 2A4082 as the front shock-absorber lever-arm buffer, which narrows its assembly role but does not locate this car’s attachment or loaded contact. No new rebound stop or suspension travel limit is inferred. The existing AHA6378-style inner spring stop remains a separate comparison.

Native export

Build this reference before rebuilding the front structure; the latter reads the declared pickup construction from this export. Checks cover valid solids, open local passages, scale and retained reference stations. They do not certify fitted operation, strength or service access.