2006 Sportster 4-Tech SCIC goes less than 5 mph

[ChicagoFunSize]

I took the boat out for about 2 hours and on the way back to the dock, I heard this vibration and the boat slowed down to approximately 5 mph at 1000-2000 rpm. I tried revving it up higher but it was of no use and couldn't go any faster - the rpm did go higher, and engine gets louder but the speed is the same. I limped at that slow speed until I got safely to the dock and towed it back to my garage. Here is what I have done.

1. I took the jet pump off, checked the spline and there were no shavings and the spline looks fine on both the shaft and the impeller.
2. I spun the impeller to see if there are any noise in case the bearings go bad but it was nice and quiet.
3. I also took the impeller cover off to inspect and it is nicely lubed.

I would like the forum's advice before I take the drive shaft off to inspect the other end. I don't have the Drive Shalf holder and I also don't have the Drive Shaft ring tool so I'll check the forum first before I spend money on getting the tools.

Thanks!

 

[Burner71]

Supercharger

 

[ChicagoFunSize]

Can you elaborate why it's the supercharger and how can I check before sending out for work? Thanks!

 

[Burner71]

Just because mine did the exact same thing when the bearings went in mine. Made a rattling noise and I couldn’t get the boat over 3-5mph and barely running. My mechanic looked at it the next day and confirmed. I would say try to get in there and spin it and see what it does.

 

[ski-d00]

You got something stuck in your pump and it fell out when you took the boat out of the water. Put it all back together and test it and I'll but it runs like new. Very common problem.

 

[ChicagoFunSize]

Here's is an update to my incident. I put the jet pump back by adding lubes, used loctite, and toqued to specs. I took the boat out and it reved up fine and was running fine the whole trip. I don't have the hours on the boat but I'll have the supercharger rebuilt at the end of the season. Thanks