Knocking at idle but runs normal

[Winter sucks]

I have a 1999 760xl and everything seems to be normal except for loud knocking at idle only. Slight throttle and it goes away. The knock just came out of the blue after a 2hrs ride. 10 hrs on SBT engine.

[Technical Support]

Re: Knocking at idle but runs normal

What is your idle speed set at out of the water?

[Winter sucks]

Re: Knocking at idle but runs normal

Idle is at 1300rpm out of the water. My other two identical skis are at 3000rpm. I take it that's the problem that's causing the knock? Thanks in advance.

[Technical Support]

Re: Knocking at idle but runs normal

Yes. Turn it up to 3000.

[Winter sucks]

Re: Knocking at idle but runs normal

Well, I turned up the idle and took it out for a spin. After that the pump started acting up (LOUD screeching noise) so I now have a different project. Took the pump apart to find that the bearings in the impeller duct assy. was shot. Now have everything but the intake duct off (the big piece that the drive shafts slips into). All the bolt are off but can't seem to get that sucker off. Question is, what's behind that piece and do I need to replace it since I have everything apart. Is there an article here on how to rbuild a pump for this ski? Can I purchase one somewhere?

[Technical Support]

Re: Knocking at idle but runs normal

The parts are dealer only, and you need the Service Manual for instrustions. It's siliconed on and you need to carefully pry and pull it off.

[Winter sucks]

Re: Knocking at idle but runs normal

The intake duct wasn't as bad as I thought. I took a thin metal putty knife that is two inches wide and tapped it in with a hammer around the perimeter of the base on the duct to break the silicone. You only need to go in about 3/4 of an inch all around. after that stick a pry bar and wedge it between the hull and the top of the duct and slowly pry it. Now the question. There seems to some type of (ceramic seal?) at the end of the duct that looks like it snapped off. One half is stuck in the duct and the other in the hull where the coupler bearing is. I can't seem to find this part on the parts list anywhere. What is it, and how do I get it out on the coupler bearing housing side? Maybe I should of tapped the silicone then slowly pull/twist it out rather than prying down?

Also, I have a bad drive shaft but only aft of the impeller. Does SBT sell the impeller shaft separately or does this model only come with a one piece drive shaft like the dealer said and quoted for $275? Thanks

[Technical Support]

Re: Knocking at idle but runs normal

As the dealer said, it's one shaft. You ned to get everything through them.