IsItAGoodCar
Reliability Guide

Common Problems with the
1973 Triumph Spitfire

We've identified 3 known issues that can affect the 1973 Triumph Spitfire. 3 of these are serious faults that could be expensive to repair.

3
Known Issues
3
Serious
0
Moderate
0
Minor

All Known Issues

Front suspension vertical-link trunnion seizure and breakage

SeriousSuspension & Chassis

The front suspension uses threaded brass trunnions that screw onto the bottom of the vertical links. Triumph specified EP90 hypoid gear oil for lubrication. In practice, owners and fast-fit garages pumped standard chassis grease into the nipples; grease hardens, dries out, and allows road grit to wear the threads. The trunnion seizes solid, causing metal fatigue that snaps the vertical link kingpin under steering load.

Est. Repair Cost: £200–£450
Warning Signs:

Stiff, heavy or notchy steering resistance when turning the steering wheel at parking speeds, Audible squeaking, groaning or grinding noises coming from the front wheels over road undulations, Visible excessive negative camber or leaning wheel if the lower brass threads have stripped

What to Inspect:
  • Inspect trunnions for grease gun nipples versus proper oil injectors; hardened yellowish grease is a red flag
  • Jack the front wheel off the ground and rock the road wheel top-to-bottom to feel for trunnion thread play
  • Verify service records show regular 6,000-mile lubrication with EP80/90 hypoid gear oil
  • Examine the threaded spindle of the vertical link for rust pitting, cracking or stripped threads
Verified by IsItAGoodCar Research TeamUpdated

Crankshaft thrust washer wear and end-float damage

SeriousEngine

On Standard-Triumph four-cylinder engines—most acutely on the long-stroke 1493cc unit fitted to the Spitfire 1500—the semicircular copper-lead crankshaft thrust washers wear excessively. Repeated clutch disengagement pushes the crankshaft forward. Once thrust washers wear down, they drop into the engine oil sump; the unguided crankshaft then machines directly into the cast-iron cylinder block web, destroying the engine casing.

Est. Repair Cost: £600–£1,800
Warning Signs:

Visible fore-and-aft movement of the front crank pulley when the clutch pedal is pressed, Difficulty selecting first or reverse gear due to excessive crank movement preventing full clutch release, Flickering oil pressure warning light at hot idle and metallic scraping noises from lower engine

What to Inspect:
  • Have an assistant repeatedly press and release the clutch pedal while you watch the front crankshaft pulley for axial movement
  • Measure crankshaft end float with a dial gauge or feeler gauge; play exceeding 0.008 inches requires immediate attention
  • Drop the engine oil and inspect the sump drain magnet for detached bronze thrust washer fragments
  • Listen for deep knocking or rubbing noises from the bottom end during clutch engagement
Verified by IsItAGoodCar Research TeamUpdated

Chassis outrigger, floorpan and sill corrosion

SeriousBodywork & Rust

The Spitfire relies on a central double-backbone chassis with fabricated sheet-metal outriggers that support the outer sills and body tub. Road spray thrown from unshielded wheels rots the outriggers, floorpans, rear axle kick-ups and outer sills. Because the sill assemblies provide vital longitudinal stiffness to the open convertible body tub, severe rot causes structural flexing, scuttle shake, and sagging door gaps.

Est. Repair Cost: £800–£2,500
Warning Signs:

Uneven door panel gaps that close up at the top or scrape the striker plate when closing, Noticeable body tub flex or scuttle shake when driving over rough road surfaces or railway tracks, Perforated holes and crumbling metal along the chassis outriggers behind the front wheels, Wet carpets and soft, corroded floorpans around seat mounting brackets

What to Inspect:
  • Inspect all outriggers and side rails underneath with a bright inspection torch on a vehicle ramp
  • Check that chassis mounting points remain properly bolted to the body with intact rubber insulation pads
  • Examine the front bonnet D-plates, headlight eyebrows and front valance for tinworm and poor fibreglass repairs
  • Verify that the battery tray bulkhead and spare wheel well in the boot floor remain free of rust
Verified by IsItAGoodCar Research TeamUpdated

Buying Tips for 1973 Triumph Spitfire

  • Check chassis outriggers and main rail rails on a ramp or pit: the separate chassis carries the entire structural load, and bodged welding or rust repairs are costly to rectify.
  • Verify that the front lower trunnions have been lubricated with heavy gear oil (EP90) rather than grease; dry or seized trunnions can shear the vertical link without warning.
  • Check crankshaft end float on 1500 models by levering the crank pulley or having an assistant depress the clutch while observing front pulley movement.
  • Ensure the forward-hinging clamshell bonnet is properly aligned; misaligned hinges cause severe panel chafing and scuttle damage.
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