One of the mainstay brands of the boat motor industry is Mercury outboard motors. Today, easily sourced parts and providing top-notch service has been a mainstay of Mercury’s success and remains true. Mercury outboard water pump replacement is a simple procedure to do.
Why replace your own Mercury outboard water pump
The water pump is one particular part that often wears out on all outboard motors. The water pump is a device that utilizes a rubber impeller to draw water up through the engine housing and into the engine compartment to cool the engine.
And a common maintenance practice for Mercury outboards is called water pump replacement, which could be performed in a matter of minutes by a seasoned pro or under half an hour by a novice boat mechanic.
How to install a replacement water pump in a Mercury outboard motor
It’s a simple easy to follow instructions below:
Things you will need:
- Mercury outboard water pump replacement kit
- Engine oil
- Screwdriver
- Helper
- Ratchet set
- Boat Motor Vice.
Mercury Outboard Water Pump Replacement Steps
- In order to install the replacement of a water pump in a Mercury outboard motor, the bolts from the lower gear housing, or known as the portion of the motor that has the prop attached, which should be removed, is the first thing you should do. Be sure the transmission is in neutral and that all four bolts are removed from the housing.
- The lower housing must be pulled away from the upper housing slowly but firmly. The only things holding the two parts of the housing together at this point will be the transmission shaft, driveshaft and wiring harness. The wiring harnesses must be disconnected and the lower housing the rest of the way must be pulled off.
- The lower housing in an engine vice with the driveshaft pointed up or parallel need to be mounted to the ground. By using the ratchet set, remove the four bolts holding the water pump onto the transmission. The water pump housing needs to be moved up over the driveshaft carefully.
- Pry the impeller out of the housing by using a screwdriver and examine it for cracks or inconsistencies also. The interior of the water pump housing should also be inspected for gouges, cracks or general wear.
- The water pump gaskets that still attached to the top of the transmission housing must be removed. There should be three in this order: rubber gasket, metal gasket, rubber gasket. It should be replaced with the new gaskets from the water pump repair kit or called Mercury outboard water pump replacement. Make sure to lube the gaskets with the engine oil prior to mounting.
- The new impeller needs to be slide down the driveshaft before you seat the water pump housing on top of it. In order to bend the impeller fins in the correct direction, while pushing down on the water pump housing, give the driveshaft a slight clockwise turn. The four water pump bolts are all ready to be reinstalled now, and also, slide the transmission housing back into place with the motor housing.
- The wiring harnesses could also be already to reconnect, mount the upper and lower housings together and replace the housing bolts. By lowering the motor into the water and turning it on, the water pump could be easily tested. If the pump is working correctly, water should spray in a stream out of the water purge hole.
