After bearing change cavitation

[Marvin willis]

It was a nice day so I finally had a chance to take out the boat. Both sides had cavitation issues. I didn't caulk any of the pieces when reinstalling. I felt like I should but didn't see anything in the manual. Gonna caulk tomorrow. Thoughts?

One other thing does anybody know how to pull off the pad to the side of the captains chairs on the wall under the window

 

[Bruce]

How do the pumps sound on the trailer? Mine were almost silent after changing the bearings.

I used RTV when reassembling the pump sections behind the impeller. I have installed them with and without sealant before and have never noticed a performance different.

Could you have installed the impellers on the wrong sides?

 

[Marvin willis]

No because I did each side 3-4 months apart. One at a time

 

[Bruce]

3 - 4 months apart, wow that is a long time for the boat to be down.

So what about the sounds. How do the pumps sound on the trailer? Mine went from baby rattle before the bearing change to quiet as a mouse afterward.

 

[Marvin willis]

They sound great. I do think one of the impellers is too tight because my throttles aren't inSync anymore and the starboard engine didn't go much over 9000 rpms

 

[Bruce]

How would you get it too tight?

Do you have any pictures of the bearing, shaft and impeller reassembly? Is it possible that the shaft is not correctly positioned in the bearings?

 

[Marvin willis]

Port side no noise. And starboard very little

 

[Marvin willis]

That's is exactly what I'm thinking. Gonna pull it apart tomorrow and adjust it. I did the first one at the end of the season and didn't get around to the other until much later. Wasn't in a hurry since it was the off season

 

[Bruce]

I would think that if the bearings were damaged during assembly you would hear noise from them.

 

[Bruce]

The bearings do have to be perfectly positioned or the impeller will be out of place. It should spin freely after assembly. You can see pics and find links to instructions in this thread https://jetboaters.net/threads/chan...-and-switching-to-oil-bath-lubrication.10155/ . I did push one bearing too far onto the shaft and had to drive it back when I was assembling.

Do I remember correctly that you also installed new pump housings with plastic liners? Do you think those could be the issue?

 

[Marvin willis]

I already had one plastic liner. Now I have both. No performance issues. Even with the cavitation it still pulls out of the water easily. Have to say the port side is more responsive. Which is weird because at first starboard was better. Port side was really bad and got better

 

[Bruce]

What do your impellers look like?

 

[Marvin willis]

I can take pics tomorrow. It will be nice having both off together so I can compare everything

 

[Marvin willis]

Big waste of time. Spark plugs. Cranked the motors and starboard barely ran. I'm guessing that's why starboard started out bad and cleared itself

 

[Marvin willis]

For some reason it's the starboard side that always fouls plugs at least once a year

 

[Marvin willis]

I don't understand why the port side plugs always look old and black and the starboard side that fouls always look new and wet. I understand it's fouling bc its wet but why does it alway look new and is there a way to adjust the fuel

 

[Bruce]

I don't understand why the port side plugs always look old and black and the starboard side that fouls always look new and wet. I understand it's fouling bc its wet but why does it alway look new and is there a way to adjust the fuel

Perhaps start a new thread on that topic so those in the know will see the subject. It might be an issue with injectors that may be related to water damage in one of your ECUs.

 

[Marvin willis]

So after the plug change starboard side (wet side) hit 11,000 rpms on the trailer and port hit 10,500. Never tried that before but was suprised that it let me hit the high.

 

[Marvin willis]

I won't be able to do a sea trial for another two weeks. I'm sad bc I head for the mtns Friday and it's gonna be close to 80 all next weekend

 

[Marvin willis]

Now that that crisis is over (fingers crossed) does anybody know how to removed the piece on the side of the boat beside the captains chairs?