Knocking Sound at Idle

[Haych]

Hi all,

When I put my ski on the water, the ski has a knocking sound only at idle, if you rev it a little, the sound goes away.

If the ski is idled outside of the water, you can not hear the knocking sound, it sounds like an engine mount, but when trying to shake the engine by hand, it doesn't move at all, its so stiff!

Its always been like this, and the jet ski runs fine!

Any ideas what it could be?

 

[hardtarge]

drive line rattle? still have your pusher spring in the pump cone?

doesn't matter it won't hurt anything

 

[kustomkarl]

Is it idling at about 1,500rpm's in the water and about 3,000rpm's on the hose? Has any work been done on the engine recently?
You need to locate the knocking sound...place a blade end of a screwdriver on the engine near the crank cases and put the handle end to your ear. The screwdriver will pick up the knock, and amplify it. Move it around till you locate it. If it is a crank knock or piston knock, it could be an expensive to repair.

Karl

 

[boatmonkey82]

its your articulating gimbal module or the muffler bearings . pull the pump and idle it down some and see if it goes away , if so then its in the pump , fi not then its in the motor . noises can be hard to diag with out being there . all we can offer is suggestions

 

[ski-d00]

sounds like the standard seadoo pump knock, very common, doesn't hurt anything, just annoying. some people turn their idles up a little to minimize it.

monkey, you forgot to mention that it could be the spitzer valve or the gonkulator.:rofl: