Katolight — Testing Thermostats Opening Temperature
Testing & diagnosis
From a Katolight manual covering: 10.5 L, 12.5, D415FGJ4, D415FJJ4, D415FNJ4, D415FPJ4, D415FRJ4, D41S5FRJ4, KDGC-2001, KDGC-500, PowerTECH 10.5/12.5 L, UN-1GNOVOS. Check it applies to your exact model before use.
Applies to: Katolight D415FGJ4, Katolight D415FJJ4, Katolight D415FNJ4, Katolight D415FPJ4, Katolight D415FRJ4, Katolight D41S5FRJ4, John Deere 6125 HF 070 engine, John Deere 6125HF070 engine, Katolight 6125HF070 engine
Before you start
- Do not allow thermostat or thermometer to rest against side or bottom of container
Procedure
- Remove radiator cap and partially drain cooling system.
- Remove four cap screws and thermostat cover.
- Remove gasket and both thermostats.
- Inspect thermostats for corrosion or damage.
- Suspend thermostat and thermometer in water and heat.
- Stir water, observe opening action against specification.
- Observe closing action as it cools; replace as matched set.
Tools required
Tool links are Amazon searches (affiliate links); manufacturer special tools may only be available from a dealer.
Specs & values
- Initial opening 80-84 C (175-182 F)
- Full open 94 C (202 F)
Full service-parts list: Katolight D415FGJ4 →, Katolight D415FJJ4 →, Katolight D415FNJ4 →, Katolight D415FPJ4 →, Katolight D415FRJ4 →, Katolight D41S5FRJ4 →, John Deere 6125 HF 070 engine →, John Deere 6125HF070 engine →
Source: Katolight 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.