Hercules — Thermostat Removal and Installation
Repair & overhaul · cooling system
From a Hercules service manual covering: D-1500, D-1700, D-2000, D-2300, D-3400, De3000. Check it applies to your exact model before use.
Applies to: Hercules D Series engine
Procedure
- Open radiator drain cock and drain enough coolant.
- Loosen hose clamp and disconnect water return hose.
- Remove thermostat housing and gasket by removing four bolts and lock washers.
- Remove thermostat.
- Install thermostat with cone-shaped end pointing out.
- Install housing and new gasket; connect return hose and fill radiator.
Source: Hercules 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.