Impeller Pump location

[Chexi]

In my quest to continue learning all there is to know about my Nautique (and to treat it right), I was scoping out the engine yesterday and planning my summerizing project for March. Can anyone confirm that I have correctly located the impeller pump? It seems pretty far away from the raw water intake with it being at the front of the engine, but it is connected to the raw water intake and I guess the front of the engine is where all the belts and pulleys are.

[DavidF]

Yep, that's it. Before you remove the pump, notice whether the large screw head on teh side of the pump is facing toward or away from the engine block. Upon re-installing the pump, orient the screw in the same direction as before pump removal. Otherwise, you will pump water from the engine into the lake....not good!

Once the pump is on the work bench, three bolts will seperate the pump body and the impellare simply slides off the keyed shaft. You can only assemble the two halfs of the pump one way (bolts are not uniformly spaced).

When I winterize, I remove the pump, remove the impellar and then place the imellar on a shelf. This helps to prevent the impellar from taking a "set". But, it will be okay to just remove the pump or do nothing (leave in boat) with it when winterizing. Just make sure to at least drain all the water from the proper places.

[Chexi]

Thank you David. I have a new impeller to put in this year. Next year I will remove the old when I winterize. By doing so, maybe I will not need to buy a new one every year.

[DavidF]

Impellars should last two years at a minimum. Four or more years if you take care of it. Don't run the engine without water for more than a few seconds (like to see if it is going to start). Some will say NEVER, but my experience has indicated a few seconds is ok.

[DanielC]

I am one of those who say never run your boat without supplying water to the raw water pump. Here is why. Is is true the pump will get water when you start it without supplying water, until all the water lines, trans oil cooler, raw water strainer, and v-drive are emptied, but the next time you start your boat, all that plumbing has to be refilled before the impeller gets water to keep it from damage.
If your impeller is damaged, you will not notice it until you are well away from the dock, when your impeller fails completely, possibly leaving you stranded in a less than desirable location.

[boatech]

i have always "quick started"/run with no water for lets say 5 seconds. before i leave to make sure the battery is up and boat will start when i get to ramp . have never had any problems and my impellers look good after 3yrs/300hrs. so i see no real harm in it. but never run it or more than a few seconds.

[j2nh]

I change the impeller every year and keep a spare in the boat. It might last 2 years or maybe 4 but why chance it? Impeller is 30 bucks, cheap considering a failure is going to take you off the water at a minimum, possibly leave you stranded, and maybe, just maybe do some serious damage to the engine. Kind of like changing the oil at the scheduled maintenance interval, you don't absolutely have to but why wouldn't you?

[Mikeski]

I fire the boat at the top of the ramp every time before it hits the water too. I roll it over, as soon as it fires I shut it down, maybe runs 2 seconds. I change my impeller every other year regardless of hours (up to 200 hours). I have not had any issues. I do carry a spare old impeller and the tools in case I do. On the last boat I had a leaky strainer seal causing the pump to lose prime and the impeller to fail. Changed it twice in one weekend.

Learn how to change your impeller on the water, carry a spare, carry the tools. Be prepared so you don't get stranded on the lake with your family.

[Chexi]

Sound advice.

[DavidF]

I told you some would say NEVER run it dry. Make your own decision. What I will tell you is that you should inspect the impellar at least every year. This will give you a good indication of how well you are treating it. Me personally, i remove the impellar at the end of each season and place it in a baggie on my work beanch (shelf). I usually get four comfortable years out of an impellar. I also frequently start the engine without a water source. Never longer than say 5 seconds. If then the impellar is allowed to cool, another few seconds while the pump is priming (when in water) is not an issue.

Bottom line is do what you are comfortable with regardless of what others recommend.

[8122pbrainard]

And I replaced my impellers 28 years ago in my dual cavity RWP on my 312. 28 years and still going strong because they are NEVER run without water. $30 a year? Add it up!!!