Re: changing impeller on 4hp
Bradford,<br />You're on the right track. You didn't mention the model number, so the year is a guess. Anyway, you'll probably see 4 bolts holding the lower unit to the motor, remove these. Since you don't have a gear shift, there's no shift linkage to disconnect. The lower unit should just drop down. You'll see that the drive shaft goes thru the water pump. You'll also see the water tube. Water is pumped up this tube and into the powerhead to keep the motor running cool.<br />Disassemble the water pump and have a look at the condition of the impeller cup. If the cup or the bottom wear plate are worn, buy the full water pump kit. All the parts you'll need come in the kit. A service manual will walk you thru the rebuild of the pump. Without a manual, it's still an easy job, just assemble the new parts the way the old one's came off. <br /><br />There's no oil at the water pump. The lower unit has the lube. It would be a good idea to drain and replace the oil before you finish the water pump. If there's water in the lower unit, you'll see a milky color, that's water mixed with the oil. We can cover that problem later if you find water. Otherwise, replace the lower unit lube, then finish the water pump/impeller.<br />Be sure to apply grease to the drive shaft splines upon re-assembly, it keeps the driveshaft from seizing with the crankshaft.<br /><br />Run motor in a test tank (barrel) with enough water to fully cover the lower unit. When the water pump is working, you should see a fine mist comming from the small row of holes on the rear of the motor's exhaust tube.<br /><br />Report back and let us know how things go.
