How to Repair a Mercruiser Alpha One Water Pump
- 1). Place the throttle into the forward position by pressing the button on the throttle lever and pushing it toward the front of the boat.
- 2). Place a drain pan under the outdrive and remove the drain plug, using a ratchet and socket. Allow the gear oil to drain from the outdrive.
- 3). Remove the zinc plate on the outdrive, using a ratchet and socket. The ratchet must be placed through the hole on the upper housing in order to reach the bolt.
- 4). Remove the four bolts securing the upper housing to the lower housing on the outdrive, using a ratchet and socket. This will allow you to remove the lower unit. Place the lower unit onto a clean workbench.
- 5). Remove the water pump housing cover by removing the four bolts, using a ratchet and socket.
- 6). Remove the water pump from the drive shaft by sliding it off the shaft.
- 7). Place the new water pump onto the shaft. Reinstall the housing and tighten the bolts, using a ratchet and socket.
- 8). Reinstall the lower housing onto the upper housing and tighten the bolts, using a ratchet and socket.
- 9). Fill the outdrive with gear oil.
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