# Radiator cap pressure test (NA6)

Canonical URL: https://miatatorque.com/spec/radiator-cap-test-pressure-na6/

Applicability: NA 1990–1993 (B6) — Other years inferred from 1990 factory evidence.

Confidence: fsm

74–103 kPa (0.75–1.05 kg/cm², 11–15 psi); hold about 10 s

Always confirm against your factory manual. Match every restriction and follow all stages and procedure notes. Disputed claims must not be automatically resolved. The complete record below preserves every printed unit, source claim and procedure.

```json
{
  "id": "radiator-cap-test-pressure-na6",
  "name": "Radiator cap pressure test (NA6)",
  "aliases": [],
  "applies_to": [
    {
      "gen": "NA",
      "years": [
        1990,
        1993
      ],
      "engines": [
        "B6"
      ],
      "note": "Other years inferred from 1990 factory evidence."
    }
  ],
  "kind": "non-torque",
  "value_text": "74–103 kPa (0.75–1.05 kg/cm², 11–15 psi); hold about 10 s",
  "procedure": {
    "notes": "Remove cap only from a cool engine. Clean residue from cap valve and seat. Attach to cap tester with correct adapter, apply pressure gradually and wait about 10 seconds; verify pressure has not decreased. Cap test, not cooling-system leak-test pressure."
  },
  "confidence": "fsm",
  "sources": [
    {
      "source": "fsm-1990",
      "page": "E–6 (PDF p. 136)",
      "as_printed": "74—103 kPa (0.75—1.05 kg/cm², 11—15 psi)",
      "verified_years": [
        1990,
        1990
      ],
      "document": {
        "id": "fsm-1990",
        "tier": 1,
        "title": "1990 Mazda MX-5 Miata Workshop Manual",
        "part_number": "1193-10-89C",
        "covers": [
          {
            "gen": "NA",
            "years": [
              1990,
              1990
            ],
            "engines": [
              "B6"
            ]
          }
        ],
        "url": "https://archive.org/details/1990-mazda-mx-5-miata-workshop-manual_202411"
      }
    }
  ],
  "jobs": [],
  "system": "cooling",
  "component": "inventory-pass-2026-10",
  "componentName": "Service measurements and fasteners",
  "sequence_diagrams": [],
  "url": "https://miatatorque.com/spec/radiator-cap-test-pressure-na6/"
}
```