# Engine coolant type and antifreeze mixture (NA 1.8)

Canonical URL: https://miatatorque.com/spec/coolant-type-and-mixture-na-bp/

Applicability: NA 1994–1997 (BP) — Other years in this family inferred from 1994 factory evidence with owner approval; actual-year verification is separate.

Confidence: fsm

Ethylene glycol-based coolant mixed with soft (demineralized) water; By volume: 35% coolant / 65% water for protection above −16°C (3°F); 45% / 55% above −26°C (−15°F); 55% / 45% above −40°C (−40°F). Do not use alcohol- or methanol-based coolant.

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": "coolant-type-and-mixture-na-bp",
  "name": "Engine coolant type and antifreeze mixture (NA 1.8)",
  "aliases": [],
  "applies_to": [
    {
      "gen": "NA",
      "years": [
        1994,
        1997
      ],
      "engines": [
        "BP"
      ],
      "note": "Other years in this family inferred from 1994 factory evidence with owner approval; actual-year verification is separate."
    }
  ],
  "kind": "fluid",
  "fluid": {
    "type": "Ethylene glycol-based coolant mixed with soft (demineralized) water",
    "notes": "By volume: 35% coolant / 65% water for protection above −16°C (3°F); 45% / 55% above −26°C (−15°F); 55% / 45% above −40°C (−40°F). Do not use alcohol- or methanol-based coolant."
  },
  "procedure": {
    "notes": "Ratios are by volume and depend on required freeze protection. Do not use alcohol or methanol. Follow the cited year-specific filling, bleeding and level-check procedure; never open the cooling system hot. Specific-gravity figures differ in the 2005 table and are not combined into a universal target."
  },
  "confidence": "fsm",
  "sources": [
    {
      "source": "fsm-1994",
      "page": "E–5 (PDF p. 141)",
      "as_printed": "Use only ethylene-glycol-based coolant.\nUse only soft (demineralized) water in the coolant mixture.",
      "verified_years": [
        1994,
        1994
      ],
      "fluid": {
        "type": "Ethylene glycol-based coolant mixed with soft (demineralized) water"
      },
      "document": {
        "id": "fsm-1994",
        "tier": 1,
        "title": "1994 Mazda MX-5 Miata Workshop Manual",
        "covers": [
          {
            "gen": "NA",
            "years": [
              1994,
              1997
            ],
            "engines": [
              "BP"
            ]
          }
        ],
        "note": "Mazda's base manual for 1994–97; later model years got supplements, which we haven't checked yet."
      }
    },
    {
      "source": "fsm-1994",
      "page": "E–5 (PDF p. 141)",
      "as_printed": "Antifreeze solution mixture percentage\nCoolant protection\nVolume percentage\nWater\nCoolant\nAbove −16°C (3°F) 65 35\nAbove −26°C (−15°F) 55 45\nAbove −40°C (−40°F) 45 55",
      "verified_years": [
        1994,
        1994
      ],
      "fluid": {
        "type": "Ethylene glycol-based coolant mixed with soft (demineralized) water",
        "notes": "By volume: 35% coolant / 65% water for protection above −16°C (3°F); 45% / 55% above −26°C (−15°F); 55% / 45% above −40°C (−40°F). Do not use alcohol- or methanol-based coolant."
      },
      "document": {
        "id": "fsm-1994",
        "tier": 1,
        "title": "1994 Mazda MX-5 Miata Workshop Manual",
        "covers": [
          {
            "gen": "NA",
            "years": [
              1994,
              1997
            ],
            "engines": [
              "BP"
            ]
          }
        ],
        "note": "Mazda's base manual for 1994–97; later model years got supplements, which we haven't checked yet."
      }
    }
  ],
  "jobs": [],
  "system": "cooling",
  "component": "gap-followup-2026-10",
  "componentName": "Additional factory manual gap audit",
  "sequence_diagrams": [],
  "url": "https://miatatorque.com/spec/coolant-type-and-mixture-na-bp/"
}
```