Small vibration when hard wot from stop then back off

[turbojamie]

Noticed a small vibration in my ski since adding the external IC and SC. If you hammer it hard and back out of it right away you can feel a vibration in the seat. Almost like a slight wobble in the drive shaft kinda feel. Wear ring etc is tight and good just wondering if its more a product of air back feeding though the Sc causing a small but noticeable comressor stall effect?

[ctriverguy]

Noticed a small vibration in my ski since adding the external IC and SC. If you hammer it hard and back out of it right away you can feel a vibration in the seat. Almost like a slight wobble in the drive shaft kinda feel. Wear ring etc is tight and good just wondering if its more a product of air back feeding though the Sc causing a small but noticeable comressor stall effect?

check the nose cone on your impeller... I had those same symptoms and that was my problem., mine had walked up the shaft about an inch.. good luck

[turbojamie]

check the nose cone on your impeller... I had those same symptoms and that was my problem., mine had walked up the shaft about an inch.. good luck

Nose cone is perfect, actually thought that too but when I took it apart to put the new prop in 14/19 out 15/20 in the nose cone was perfect and it still does it with the new prop swap.

[BDNJ]

Jaime-

Double check that the additional power didn't break off a motor mount. Remember the mount would rip just UNDER the rubber bushings. The best way to check is by hoisting the motor just an inch or so with a davit or a pulley. Once the weight is off you should be able to wiggle the bushings if any are broken. Also make sure your mount bolts to the hull are not lose either. One broken bushing could cause the motor to shift or torque (especially w/ more power) and cause vibration in the driveshaft since it would most-likely be out of alignment at that point.

Just a thought.

Brendan

[turbojamie]

Jaime-

Double check that the additional power didn't break off a motor mount. Remember the mount would rip just UNDER the rubber bushings. The best way to check is by hoisting the motor just an inch or so with a davit or a pulley. Once the weight is off you should be able to wiggle the bushings if any are broken. Also make sure your mount bolts to the hull are not lose either. One broken bushing could cause the motor to shift or torque (especially w/ more power) and cause vibration in the driveshaft since it would most-likely be out of alignment at that point.

Just a thought.

Brendan

Good point I will have a good look at that but I was wiggling and pulling last night with no movement. I will double check it. It only does it when you hammer and back off. I sware it feels like compressor surge but I don't see how with the slip clutch that can be.

[GTXX]

Good point I will have a good look at that but I was wiggling and pulling last night with no movement. I will double check it. It only does it when you hammer and back off. I sware it feels like compressor surge but I don't see how with the slip clutch that can be.

the clutch just slips for an instant then stops slipping, happens really quick. then you get the funny noise from the SC.

[Craigo]

Let me know what you find.

[toilets]

Ive noticed a good vibration through the steering at idle and at WOT, speeds are not affected, nor hole shot. but if you are idling and take your hands off the steering, it definitely vibrates pretty good. Nothing crazy but defnitely noticable... Could this be possibly from me taking off my nose cone?? I checked everything else and everything seems to be fine.

[BDNJ]

Having the nose cone off definitely increases vibration in the pump. I would put it back on and see if it goes away. You also could have a driveshaft/motor alignment issue.

Brendan

[toilets]

ok I will try that, Would the alignment issue be from the begninning or could this actually become misaligned over time? I have never noticed it before however we did take out my prop to repitch it and flip the wear ring recently.(that was when the nose cone came out)