Vibration / shake

[Project Ski]

Finally got my ski together and in the water this weekend. I had a vibration felt through the entire ski. When coming back down to idle it actually would feel worse.

I was thinking the engine isnt aligned properly, but before ripping everything apart i thoguht i would post and see if there was any other suggestions.

 

[WAB]

Finally got my ski together and in the water this weekend. I had a vibration felt through the entire ski. When coming back down to idle it actually would feel worse.

I was thinking the engine isnt aligned properly, but before ripping everything apart i thoguht i would post and see if there was any other suggestions.

Used, dinged, bent impeller?

 

[Project Ski]

it is a used inpeller but its not bent or dingled, turns in the pump really smooth by hand.

 

[oxnard111]

Finally got my ski together and in the water this weekend. I had a vibration felt through the entire ski. When coming back down to idle it actually would feel worse.

I was thinking the engine isnt aligned properly, but before ripping everything apart i thoguht i would post and see if there was any other suggestions.

Most likely alignment of the engine, pump, and/or short shaft housing since this is happening after you "finally got my ski together"

If the short shaft was not removed, then don't worry about it... then move onto the pump, then move to the engine...

 

[Dirtybird]

Possibly the engine to the engine cradle bolts loose. This is what happened to my ski twice. Just got done fixing it again I hope

 

[sjetrider]

bent drive shaft or motor not alligned well, you could just have the rubber coupler in a pinch.

 

[sjetrider]

after riding feel the coupler if it is hot it is one of the 2 above or bearing bad in midshaft housing.

 

[oxnard111]

after riding feel the coupler if it is hot it is one of the 2 above or bearing bad in midshaft housing.

good advice

 

[brentR]

coupler getting hot after riding.. would that effect performance?

 

[Project Ski]

this is on a Kawi X2 so it doesnt have the short shaft assembly like the SJ. Thanks for teh advice though, some good things to check.

 

[Shrivel]

it is a used inpeller but its not bent or dingled, turns in the pump really smooth by hand.

I sucked a rock into my pump last season and it chipped my impeller so slightly that you can't even see it from the outside. Once it happened my whole ride shakes at low speed just like you're describing. Grinding the ding with a dremel got rid of some of the shake, but it's still there. The whole pump system is extremely sensitive to any irregularities - I've had a single pine needle get stuck in my intake grate and cause my ski to be unride-able.

 

[Project Ski]

a pine needle???? that sounds extreme. I just realligned the engine and replaced one of the motor mounts. IF its still a problem i will look into the prop but it looks in perfect condition.

I get the vibration at higher speeds too but coming down to slower/idle it shakes harder and at less frequency. Higher speeds it seems to be more of a vibration and tighten up

 

[Crab]

When setting the engine in, there should be so little stress on the driveshaft I can easily move mine back and forth about an 1/8 inch with little effort. I let the bearing holder float until the engine is bolted down tite, then reach back and snug up the bearing holder bolts. I do not silicone it to the firewall so It can find where it wants to be, of course this is with the pump installed also. Its rare that a dinged prop will make that much vibration, but it is possible if the blades are way out of phase with each other. In other words they should all move the exact same amount of water, or the pump is out of balance and will have a severe shake. I had a rock stuck between 2 stator veins I couldn't see, and it shook so hard I was sure It threw a blade on the impeller.

 

[Project Ski]

OK i realligned the engine, changed out one of the mounts and gave it a go. Still had the vibration.... This is out of the water running on the hose. so i figure it cant be the pump. I walk around the ski and its louder at the back. There is somethign definitely not right with the pump, its banging/clanging. Weird thing is, if i put my hand on the pump its not vibrating.

I think i have a combo of things going on. the vibration definitely goes away as the engine speed increases even slightly. Im thinking with teh TL flywheel and the timing curve i could just be getting a rumble from the engine down low as it almost wants to stall???

Ill be changing my prop out to see if it gets rid of the problem.

 

[Project Ski]

anyone with more suggestions? Think its just wishful thinking that its the T/L and timing curve?

 

[yamanube]

I had a wierd vibe that I could not track down for a few days, I check my alignment, my impeller, my pump...ended up being the rubber seal on my solas prop. It had worked its way about halfway down my driveshaft, I pushed it back into the prop and the vibes went away...also picked up some lost power, I felt pretty dumb.