Showing specs for all NA & NB Miatas

Thermostat initial opening temperature (NB2 2004–2005, non-turbo)

188–193 °F (86.5–89.5 °C)86.5–89.5°C {188–193°F}

Factory manualTaken from a Mazda factory workshop manual, with page citation.
Procedure

Place thermostat and thermometer in water, heat and check the valve. Use 86.5–89.5°C initial opening for the single-valve NB2 thermostat, including Mazdaspeed. The 2003 procedure supports this range; 2004–2005 procedures/tables print 83.5–86.5°C, retained verbatim in citations where present. Full-open temperature is 100°C; minimum full-open lift is 8.5 mm. Do not apply the NA main/sub valve distinction to these NB records.

Applies to
  • NB 2004–2005 (BP-Z3) — Actual 2004 and 2005 factory evidence; initial-opening range follows the 2003 procedure.
  • Verified in: 2004 Mazda MX-5 Miata Workshop Manual (electronic manual capture); 2005 Mazda MX-5 Miata Workshop Manual (electronic manual capture); 2003 Mazda MX-5 Miata Workshop Manual (electronic manual capture)

Sources (3)

View 3 source citations
  • 2003 Mazda MX-5 Miata Workshop Manual (electronic manual capture)Tier 1
    Page Thermostat Inspection (PDF p. 655) · Printed value & notes
    Page Thermostat Inspection (PDF p. 655)
    Printed: “Initial-opening temperature °C {°F} 86.5—89.5 {188—193}”
  • 2004 Mazda MX-5 Miata Workshop Manual (electronic manual capture)Tier 1
    Page Thermostat Inspection (PDF pp. 687–688); Engine Technical Data (PDF pp. 929–930) · Printed value & notes
    Page Thermostat Inspection (PDF pp. 687–688); Engine Technical Data (PDF pp. 929–930)
    Printed: “Initial-opening temperature °C {°F} 83.5—86.5 {183—187}”
  • 2005 Mazda MX-5 Miata Workshop Manual (electronic manual capture)Tier 1
    Page Thermostat Inspection (PDF pp. 749–750); Engine Technical Data (PDF p. 1047) · Printed value & notes
    Page Thermostat Inspection (PDF pp. 749–750); Engine Technical Data (PDF p. 1047)
    Printed: “Initial-opening temperature °C {°F} 83.5—86.5 {183—187}”