IsItAGoodCar
Reliability Guide

Common Problems with the
1968 Morgan Plus 4 / Plus 8 / Roadster (Classic)

Morgan revolutionized its flagship line in 1968 with the Plus 8, pairing the widened steel chassis with Rover's lightweight 3.5-litre V8, while the Plus 4 returned in 1985 using Fiat twin-cam and Rover M16/T16 2.0L engines.

What changed for 1968

  • •Introduction of the Plus 8 powered by the 3.5L Rover V8 (initially on SU carburettors, gaining Lucas EFI from 1984)
  • •Plus 8 capacity increased to 3.9L in 1990 and an optional 4.6L Rover V8 introduced in 1996 with 5-speed Rover LT77/R380 gearboxes
  • •Plus 4 revived in 1985 with a 2.0L Fiat DOHC engine before switching to Rover M16i (1988) and T16 (1992) engines
  • •Galvanised steel chassis and factory Cuprinol timber treatment introduced as options and later standardised in the late 1990s

Common MOT watch-outs

  • !Galvanic corrosion bubbling where hand-formed aluminium wings and body panels contact steel chassis brackets
  • !Rover V8 coolant leaks, porous block or slipped cylinder liner overheating on 3.9L and 4.6L Plus 8 models
  • !Perished steering rack gaiters (on post-1986 rack-and-pinion cars) and weeping rear lever-arm or telescopic dampers
3
Known Issues
1
Serious
2
Moderate
0
Minor

All Known Issues

Ash Frame Rot

SeriousBodywork & Rust

The body panels are tacked to an ash wood frame. Moisture trapped behind the panels or under the wings can rot the wood.

Est. Repair Cost: £1,000–£5,000 (depending on extent)
Warning Signs:

Soft spots in the wood, Loose body panels, Doors dropping

What to Inspect:
  • Check the bottom of the "A" pillars and the rear wheel arches.
  • Look for "black" wood through access holes.
Verified by IsItAGoodCar Research Team

King Pin & Bush Wear

ModerateSuspension & Chassis

The traditional sliding pillar suspension relies on manual greasing. If missed, the pins and bushes wear, leading to poor handling and MOT failure.

Est. Repair Cost: £400–£800
Warning Signs:

Heavy steering, Steering "shimmy" or vibration, Uneven tyre wear

What to Inspect:
  • Jack up the front and check for vertical play in the hubs.
  • Verify the greasing history.
Verified by IsItAGoodCar Research Team

Galvanic Corrosion

ModerateBodywork & Rust

Aluminum body panels reacting with the steel chassis or fasteners can cause "bubbling" in the paint.

Est. Repair Cost: £500–£2,000
Warning Signs:

Bubbling paint on the wings or bonnet, White powdery residue at panel edges

What to Inspect:
  • Inspect panel edges and where the wings meet the chassis.
Verified by IsItAGoodCar Research Team

Buying Tips for 1968 Morgan Plus 4 / Plus 8 / Roadster (Classic)

  • Verify whether pre-2000 cars were ordered with the optional galvanised chassis and treated ash timber frame
  • Inspect Rover V8 Plus 8s thoroughly for mayonnaise under the filler cap or pressurised cooling systems indicating liner slip
  • Check for heavy steering on early cam-and-peg steering box cars versus smoother post-1986 rack-and-pinion conversions
1951–19671969–2003
Check a 1968 Morgan Plus 4 / Plus 8 / Roadster (Classic) by Registration