Kubota — Checking the Thermostat Valve Opening Temperature
Maintenance
From a Kubota service manual covering: Hurth HBW 100, Hurth HBW 125, Hurth HBW 150, Hurth HBW 250, Hurth HBW 35, Hurth HBW 50, M-25XPB, M-35B, M-40B. Check it applies to your exact model before use.
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Procedure
- Push down thermostat valve and insert string between valve and valve seat.
- Place thermostat and thermometer in container with water and gradually heat.
- Hold string to suspend thermostat in water.
- When valve opens, it falls from string; read water temperature.
- Continue heating and read temperature when valve completely opened [about 0.236 in. (6 mm)].
- If temperatures are not within standard values, replace thermostat.
Tools required
Tool links are Amazon searches (affiliate links); manufacturer special tools may only be available from a dealer.
Specs & values
- Opening temperature: 157.1 - 162.5 °F (69.5 - 72.5 °C)
- Completely open: 185 °F (85 °C)
Source: Kubota service manual. Steps and values are as documented; always cross-check against the official manual and any later revisions for your exact serial number before servicing.