Kubota Coolant
Mix Calculator

⚠️ Always Use Distilled Water

Tap water contains minerals that create scale deposits inside cooling passages, reducing heat transfer and causing premature water pump wear. Distilled water is inexpensive and critical for long system life.

🧪 Concentration Limits

• Below 30% — corrosion protection drops sharply
• 30–40% — mild climates only
• 40–60% — Kubota recommended range
• Above 70% — heat transfer worsens; avoid

📅 When to Change Coolant

Kubota recommends replacing coolant every 2 years or 600 hours — whichever comes first. Test annually with test strips to check pH and concentration.

🔄 Pre-Mix vs. Concentrate

Buying pre-mixed 50/50 coolant? Add it straight — no water needed. Using full-strength concentrate? Use this calculator to find out exactly how much distilled water to add.