Impeller Replacement?

[wawasee1]

Hello

I have been reading a lot of the posts and have read that many of you suggest replacing the impeller as one of the things SN owners should do at the end of every season. I hate to show my ingnorance in this matter but I've never done this and never new I should be doing this. Is this something I need to do with my 1989 Ski Nautique(PCM 351)? Can anyone tell me how to change it? I have been doing my own winterizing for 9 years and my marina never put it on my list of things to do each year. Any and all help is appreciated. Also, thanks to all for the ideas for my winter projects that are upcoming (previous post).

Thanks,

Mike

[NautiqueJeff]

Mike,

This is most definitely something you should do to your boat, especially if it hasn't been done for nine years. The procedure is very easy. First, order the part (http://www.whitelake.com/catalog/sherwood_impeller_kit_1653426.htm). Once you have it, loosen the front belt and open the water pump. It'll be attached to the lower left pulley as you're facing the engine. See picture below.

http://www.planetnautique.com/CorrectCraftManuals/sherwood_pump.jpg
Water Pump

It should be held together by three or four bolts. Once it is open, you'll see the impeller. TAKE NOTE OF THE DIRECTION OF THE ROTATION! Remove old impeller and replace with the new one. Make sure the vanes are bent in the same direction as the old one (you'll know what I'm talking about when you see it). Reinstallation is the reverse of removal.

http://www.planetnautique.com/CorrectCraftManuals/impeller_sherwood.jpg

[Luke]

Anyone happen to know the model # of the impeller for a '03?

Jeff I noticed the one you posted only goes up to 2002. Will it still work on a '03?

[NautiqueJeff]

Anyone happen to know the model # of the impeller for a '03?

Jeff I noticed the one you posted only goes up to 2002. Will it still work on a '03?

Luke,

Not sure if the one above will work or not. Which engine do you have in your boat? I can tell you that the PCM part number for the '03 Excalibur impeller is RP061017. Replacement looks to be slightly different than on the older engines. Take a look:

http://www.planetnautique.com/CorrectCraftManuals/pump.jpg

[skinautique]

why are you guys replacing this every year? Too many owners do way too much maintenance that isn't needed. If it doesn't get above 160, leave it alone. Is there real logic to doing it every year? Never had a problem doing it my way so I am curious what your thoughts are. The only think I see you guys doing is keeping Sherwood in business by selling more impellers.

[NautiqueJeff]

I'd agree that yearly could be overkill, but I think after nine years, it's time.

[Luke]

Thanks for the info Jeff. I have the Excalibur.

Skinautique - Your 160 rule of thumb makes sense I guess. I've heard numerous people on the other message boards suggest that you should change the impeller each year. Thanks for the info.

[wawasee1]

Thanks guys. Seems like a pretty easy change. My boat doesn't run hot but I will agree that after nine years...its probably time!!

[Levi]

In reference to the "direction" of spin of the impellor above, I've heard that it doesn't matter which way you put it in as it will twist the correct way the first time you turn over the engine. Granted, putting in the correct way would seem to be the logical way to go.

As for changing it every year, I think most people look at it like an easy insurance policy. They're not very expensive and for most people it would only take 15 - 30 minutes to change each year (non vdrive). That way you don't have one "blow" up on you way out someplace and then your looking at getting towed in..... But running one dry for a very short period of time no matter how new can be the death of an impellor. That said, I'm NO mechanic so discount my rampling as you feel appropriate! :wink:

[Edwin]

One thing that will have a say in the life of your impellar is the quality of water in which you boat. I know a few local folks who use their boats 100% on the Mississippi River and go through two impellars a year. The water is fairly shallow with suspended sand in the water. Eats them up in no time. On the other hand, impellars can go for quite some time in clean water. I always check mine at the end of the season. If there's no wear, I'll put it back in. I always have a spare on board.

As for the direction of the vanes, I feel it's important to install the new impellar with the vanes folded in the correct direction. The water pump housing is not completely round, hence a section of the housing is loose (allowing the vanes to extend nearly straight out) while another section is very tight (folding the vanes over more than 90 degrees at the hub of the impellar). All it takes is one small piece of a vane to get caught on a water passage and tear, the rest of the impellar will self destruct in rather short order.

BTW - little known fact, came from a Mercury shop manual - in a marine engine that is started w/o a source of water, the impellar will begin to fail in as little as 10 seconds.

[skinautique]

My whole thing was don't fix it if it isn't broke. If you have something that works for you than go for it.

[awake4air]

Make note of the direction of the pump assembly. A friend of mine changed the impellor on my boat and put it on backwards. This caused the pump to go from suck to blow. If we weren't careful, we could have blown the engine considering there was no water in there to cool it off.

Paul

[skinautique]

Hey Wawasse,
Did you ever change your impeller? I would love to see pics of it after 9 years!

[Nautiqueman]

As for the impeller situation... I had a 1993 SN that had an impeller problem that I had a dickens of a time figuring out!! The boat ran hotter that I like from time to time (about 200 near idle) then cooled off under power. I thought it was the thermostat since the boat was 10 years old. However, after I changed the thermostat, it still did not help. I then changed the impeller which was no good at all ... First time I ever changed one out that had lost some of the teeth. I could not find any residue in the thermostat area and my dealer told me that almost always it would blow through the engine. However.. the heat problem still existed and the boat ran HOT.. amazing to go to all this trouble and have not fixed it yet. I'm no mechanic, but I was getting pretty HOT about this boat not working right... Well, another mechanic told me to clean out the water supply before the impeller/water pump and that is where I found the problem .. there were pieces of impeller before the water pump.. I never suspected this since I didn't think water flows backward, so remember when changing a broken impeller, that pieces could be lodged in the hoze before the pump.. This is the only serious impeller problem in 17 years of Nautiques and 15 different Nautiqes..

[tryan]

impeller life is going to depend on usage and water conditions. if you have a strainer, you can see what can get sucked up into the pump. twigs, bark, leaves and pine needles have to be hard on the vanes. the recent fires have given a few west coast boaters trouble floating muck. if you run in crap, check it often. if you run in the bathtub, it should last a while.

slipping a new one on give me peace of mind and keeping a spare onboard is wise insurance. i pull mine out for the winter, so it can relax and lube it in the spring when i reinstall it. i have never had one fail, but it could happen


check out globerubber and their BLUE impellers. search for the 15 minute impeller thread.

[wakejunky]

I must say one thing about the locataion of the 03' impellors, that is they are a b*tch to change out. The problem is that they are super tight within the housing and the thing just doesn't want to come out. And if you have a v-drive it makes for on the water changes even more difficult, the impellor is down below the muffler. At least in the 04' they went to serpentine belt and relocated the pump on the top of the engine. Then at least you stand a chance of actually getting it out.

Chris

[skinautique]

I will agree they are tough but you can get to them. You have to be really flexible (your body that is)!

[ozarkcountry]

Can anyone tell me the part number for this water pump impeller? Is it something I can purchase at any marine dealers or is it something that must be special ordered?

[Red57Bird]

I must say one thing about the locataion of the 03' impellors, that is they are a b*tch to change out. The problem is that they are super tight within the housing and the thing just doesn't want to come out. And if you have a v-drive it makes for on the water changes even more difficult, the impellor is down below the muffler. At least in the 04' they went to serpentine belt and relocated the pump on the top of the engine. Then at least you stand a chance of actually getting it out.

Chris

Chris - one trick I picked up from another thread was to use two paint can openers to pull the old impeller out. I also use some boot lube as well to help coax it out. First time I replaced it was a chore, but now it isn't so bad. Only thing is that I don't like having to take the pump out of the boat each time.

[east tx skier]

We have pretty silty water around here. I change mine every spring without fail. I have seen people that boat on the same body of water lose his while making a run at a two year impeller change. I regularly used his boat as well. His temp ran right around 160 until it didn't. It climbed fast and, fortunately, the high temp was noticed before any damage was done. We then spent the better part of the afternoon backflushing and pulling little bits of impeller out of the nooks and crannies of the engine. I would have rather him paid $20--$30 so that we could have gone skiing instead or done anything else for that matter.

I change mine in the spring. If I were going to try to make it two years, I would take it out at winterization and store it in a ziploc bag. When you leave them in over the winter, they become pretty well formed to the irregular shape of the pump housing during the long layup and lose a bit of efficiency as water movers as a result.

Again, this is just what I do. The cheap insurance answer is the short one. And I don't miss one bit of the drop in the barrel I have spent on impellers while I have owned inboards. Knock on wood. I have never had one go bad on me and have never backflushed my cooling system when I should have been skiing.

YMMV

[gping43]

is it true that a bad impeller can lead to a louder engine? Took my impeller out today, it looks great. No wear, no signs of damage, but what the heck do I know. Could it still be "bad" without being visibly damaged?

[rhendle]

Looking for a little guidance on the impeller replacement process. I have an 05 sv-211 PCM Excaliber 330 with a surp belt. I've located the pump but am curious if i have to pull the alternator with the pump or is there another way? Can the impeller be replaced while leaving the pump in place? Thanks!