How to Replace a MerCruiser Alpha Thermostat
- 1). Open the engine cover of your MerCruiser to access the engine. Locate the thermostat housing. It mounts to the top of the engine near the front. There are four hoses that connect to the housing and are attached with hose clamps.
- 2). Remove the two bolts securing the housing to the engine block.
- 3). Pull the cover off the thermostat housing. Remove the gasket.
- 4). Grasp the thermostat inside the housing with pliers. Pull the thermostat out of the housing and discard.
- 5). Place the new thermostat in the housing by pressing it in with your hands.
- 6). Apply the new gasket between the cover and the thermostat housing.
- 7). Place the cover on the housing. Align the holes of the cover, gasket and housing and install the bolts. Tighten them using a ratchet and socket.
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