AR190 cavitation

[Riley Hunter]

I have a 2017 ar190 that I’m getting cavitation are hole shot. I have added ribbon delete and lucky cone 13. I did suck a rope up when I 1st bought the boat new but never noticed it until the end of last year. I thought me adding the ribbon delete and air intake made the cavitation so I added the cone but it’s still there. What direction should I go from here. I have looked under the boat at the impeller and don’t see and thing there but I have not removed it to inspect. I’m hoping I’m overlooking something so I don’t have to pull it.

 

[tdonoughue]

So, a couple of things:

1) Looks like you have some growth stuff there along the intake. I would clean that off first. You need that smooth up to the impeller. And make sure that the silicone is in all of the gaps and over the bolts along the way. If any of that has come out, put some more on and smooth that out. Fingers work best to do that (rather than a tool or scraper or anything).
B) Also looks like something is going on with your wear ring. Are you boating in salt water? If so, flushing regularly?
iii) Don't be afraid to pull those impellers to inspect. I had the same thought--don't want to do that until I have to do it. That was so wrong. It is so easy and gives you so much information. You will be able to properly inspect the wear ring, the impeller, the shaft. And very, very easy to pull and to put back. I would not hesitate on that.

 

[Riley Hunter]

So, a couple of things:

1) Looks like you have some growth stuff there along the intake. I would clean that off first. You need that smooth up to the impeller. And make sure that the silicone is in all of the gaps and over the bolts along the way. If any of that has come out, put some more on and smooth that out. Fingers work best to do that (rather than a tool or scraper or anything).
B) Also looks like something is going on with your wear ring. Are you boating in salt water? If so, flushing regularly?
iii) Don't be afraid to pull those impellers to inspect. I had the same thought--don't want to do that until I have to do it. That was so wrong. It is so easy and gives you so much information. You will be able to properly inspect the wear ring, the impeller, the shaft. And very, very easy to pull and to put back. I would not hesitate on that.

I left the boat in fresh water for 8 weeks and the entire bottom of the boat looked like that. Where can I find how to remove and inspect impellers.

 

[tdonoughue]

To pull the pumps, we have a handy FAQ: https://jetboaters.net/faq/#faq-26

I have had things like that grow on my boat over a weekend of being in constantly. Not sure what they are. If they are like mine, they are a bit raised. That could be causing cavitation. Mine always wash off with a little elbow grease and/or a plastic scraper. I would be getting those off of there...

 

[Riley Hunter]

Thanks. I will be removing mine. U also said to look at the wear ring. Can you point me in the right direction on where and what I’m looking for.

 

[tdonoughue]

Sure. In your middle picture, just before the impeller itself, you can see the part around the outside of the impeller. That is the ring. I see there is some stuff on there. I can't tell what it is from this distance (part of the reason to pull the pump). It may just be more of that same growth stuff to be cleaned. However, it may be that the ring is starting to corrode. What can happen (particularly in salt) is that ring can start to corrode and swells a little. That makes it rub against the impeller and you will see scraping marks around the inside of that ring.

Hopefully that is just more of that growth stuff to clean off. However, if you see that there is scraping on the inside or the pump is difficult to get out of that, it may indicate that you do not have the required clearance and need to change the ring. Mine is a 2012, only been in fresh water, and I have had no issues on that front. So it may very well just be growth. But with as easy as the pumps normally come off, it will make the cleanup and inspection much easier.