A few pump related questions.

[dbracela]

Went to change my carbon seals today and everything related, and also the impellers. When I pulled the thrust nozzles off (venturi?) I noticed two small holes on the inside face that were plugged with rtv. The holes seem to run into the nozzle, there are two of them. Are they supposed to be plugged?

I noticed that my ride plate is shifted about 1/8 to 1/4 of an inch into the water inlet. Could that also be affecting my cavitation issues?

It looks like, at some point, something got caught up in the driveshaft and whatever it was cut some minor grooves through the gel-coat inside the inlet, just in front of where the pump ends up seating. Should I repair that or is that a minor detail. I've been going through all this to figure out my cavitation issues on the right side.

The old carbon and pusher rings are out and look the same as the new ones, I still hope that they are the main problem.
Thanks, Dan.

 

[Dr Honda]

Post a pic of the holes. I can't visualize the part you are talking about.

If the gouge in the tunnel is into the glass... then yes, you should patch it.

If the scoop is shifted... it could have moved the ride shoe, and that could be leaking air. I would make sure your shoe is sealed since you are in there.

 

[dbracela]

the first pic is of the rideplate being off. The second is of those plugs. Sorry, but what do you mean by "Scoop being shifted?"

 

[Guest_User]

Went to change my carbon seals today and everything related, and also the impellers. When I pulled the thrust nozzles off (venturi?) I noticed two small holes on the inside face that were plugged with rtv. The holes seem to run into the nozzle, there are two of them. Are they supposed to be plugged?
Those are the bailer tube holes in the exit nozzles. The boats don`t use the bailer system like the ski`s do. The pumps are missing the bailer top cap. I also see mine are sealed with silicone. One has managed to blow out this silicone, I noticed it when I was rinsing the pump off with the hose.

I noticed that my ride plate is shifted about 1/8 to 1/4 of an inch into the water inlet. Could that also be affecting my cavitation issues? Like Doc mentioned, pics...is it possible it was removed or replaced at one time? does it look original? I don`t think that little bit of offset would affect cavitation, but it not being sealed properly certainly can.

It looks like, at some point, something got caught up in the driveshaft and whatever it was cut some minor grooves through the gel-coat inside the inlet, just in front of where the pump ends up seating. Should I repair that or is that a minor detail. I've been going through all this to figure out my cavitation issues on the right side.
The previous owner of ours sucked up a 2x4 from someones new dock, and it spun around until it wore a nice spot down into the fiberglass... Yes, repair this, marine tex 2 part epoxy is good for this...

The old carbon and pusher rings are out and look the same as the new ones, I still hope that they are the main problem.
Thanks, Dan.

cavitation can be from several things, the wear rings the impeller edges worn down, but most likely the carbon seal`s leaking air. also check the tension the carbon seal has on the floating ring after it is installed...
Good luck!

 

[dbracela]

Did my pics work? Does it look like the ride shoe or scoop being shifted needs to be fixed? I would imagine the shoe screws go into pre determined holes in the hull, therefore I couldn't just take it off and move it over, could I? Should I just try my best to seal in as is?

 

[Dr Honda]

I would try to seal it as is.

 

[dbracela]

will do, thanks guys. Will post an update when I get it all done and water test it.