Monday, October 12, 2009

Working on the Boat Motor - Impeller Replacement

Now that the boat is out of the weather, we can start working on it to fix or fix-up all the wear-n-tear from the last year of fishing and camping.

Last time out, our main motor got hot and started to overheat - especially as we idle or slowly motor around. When we throttle up the engine cools down a bit, but is still running hotter-than-normal. I suspect the impeller isn't pumping enough water at slower speeds...

So, we tore into the lower gear-box on the motor. Pretty straight forward to open it up - first remove a few 5/8" nylon nuts to drop the lower end off.

Also, we need to remove the trim-tab. We first made sure to mark the angle it was at for re-installing.

Pretty straightforward - didn't even need to take the prop off.

And off drops the lower end of the motor.

The longer bolts help guide the drive shaft and water tube into place...

Here is the detatched lower end.

Not too bad so far...

Here's a close-up of the water pump housing, bolts, etc.

Instead of clamping the assembly in a vice, we worked up a quick-n-easy clamp to hold it up while we dis-assemble the impeller housing.

Works great!

Here is the housing lifting off the drive shaft.

And here is the impeller inside the housing. The old one looks pretty good.

After replacing the impeller, we re-assembled the unit in reverse order of tear-down. The hardest part was simply aligning the impeller on the drive shaft with the gear-tooth aligned that spins the impeller.

Took about an hour. No major issues encountered! Now... lets fire it up and see if it runs!