weird sound from pump

[ISeeWetPeople]

That metal sound coming from the pump when you start/run/stop your engine on a trailer.. What it is and why does it exist in so many jetskis?

I just bought a new engine, my coupler and pump bearings are new and ive shimmed my engine using shim tool made for it..

 

[eastcoastjumper]

The midshaft and driveshaft splines wear out after so many hours.

 

[jetpilot36]

maybe your wear ring is swelling in a spot and its hitting your impeller blades.

 

[Freakrider]

Take the plugs out and turn motor over by hand with the coupler and listen and feel for impeller rubbing inside impeller housing.

 

[ISeeWetPeople]

Yes my thought too. But im pretty sure that this sound comes with plastic wearring too..
its just weird that even new 2014 sj sounds like it.. and i listen to tree seadoos and two kawasaki 310 same sound.. and they are brand new..

But that is about the only explanation there is i think..

 

[Lumpy]

Pumps have been rattling on trailers since the 90s I wouldn't sweat it

 

[Harbor]

I always thought the idle rattle on trailer was from the mid shaft and drive shaft spline clearance. With no load on the prop while at idle you hear the drive and coast side of the splines slapping as the crankshaft speeds up and slows down during and after each power stroke. All the skis here do it and my friends STX couch does it since new

 

[Tyler Zane]

The midshaft and driveshaft splines wear out after so many hours.

uh, not exactly.. if greased regularly with the spline grease they shouldn't "wear".

 

[SUPERJET-113]

uh, not exactly.. if greased regularly with the spline grease they shouldn't "wear".

They all wear eventually, but yeah the grease acts like a cushion.. There has to be a little tiny bit of play so that you can assemble.

 

[ISeeWetPeople]

Ok so need to worry.. but my guestion was what cause it.. but im pretty sure harbor is correct...

 

[Kaup_921]

I chased this issue on one of my skis for a while and it ended up being play between the couplers. I ended up having to replace my couplers because even with a brand new rubber dampner it would still have play in it. But it could be an issue with alignment, driiveshaft/midshaft splines, swollen wear ring, or worn out bearings. Take the plugs out and roll it over by hand. Rock it back and forth and check for play.

 

[ISeeWetPeople]

Ill try that.. thanks

 

[Tyler Zane]

They all wear eventually, but yeah the grease acts like a cushion.. There has to be a little tiny bit of play so that you can assemble.

Sure, there has to be clearance but its not a normal inspection interval as opposed to wear ring to impeller clearance. It shouldn't make noise and in theory it should last the lifetime of the watercraft. Unfortunately they do strip but from what i have gathered its typically from misalignment or worn midshaft housing/pumps allowing too much movement.

Sorry if we are getting off topic OP and I say all this with respect to SUPERET (thanks for always being there on gaskets).

 

[ISeeWetPeople]

How about driveshaft torsion when landing on water with high throttle. Could that twist my shaft so that could make the noise. My pump allignment is spot on i used cold fusion tool for that.. (at least i hope so)

 

[eastcoastjumper]

How about driveshaft torsion when landing on water with high throttle. Could that twist my shaft so that could make the noise. My pump allignment is spot on i used cold fusion tool for that.. (at least i hope so)

Take out your motor and turn your midshaft coupler left and right with your hand. Put the ski on a shop stand so you can reach under and hold the driveshaft, or have someone hold it for you. I guarantee you will feel a small amount of movement between your midshaft female splines and your male driveshaft splines. Even if you have grease in there it will chatter when its wears out. You can ride it like that for a while before its gets really bad, it takes hundreds of hours but it happens. One day they will strip and you just replace both shafts. New OEM is $$$. If you ever have your pump out just take a look at the splines. They wear on one side mostly and start to get peaks rather than the square edge they start out with.

@tzane whats the "lifetime" of a jetski and its parts? People are buying used parts all the time. Some of these parts see all kinds of HP, and hours of use.

side note : Look at kawi 650 pumps where those driveshafts just press into the impeller splines. Those things chatter like crazy.

 

[Tyler Zane]

Take out your motor and turn your midshaft coupler left and right with your hand. Put the ski on a shop stand so you can reach under and hold the driveshaft, or have someone hold it for you. I guarantee you will feel a small amount of movement between your midshaft female splines and your male driveshaft splines. Even if you have grease in there it will chatter when its wears out. You can ride it like that for a while before its gets really bad, it takes hundreds of hours but it happens. One day they will strip and you just replace both shafts. New OEM is $$$. If you ever have your pump out just take a look at the splines. They wear on one side mostly and start to get peaks rather than the square edge they start out with.

@tzane whats the "lifetime" of a jetski and its parts? People are buying used parts all the time. Some of these parts see all kinds of HP, and hours of use.

side note : Look at kawi 650 pumps where those drive shafts just press into the impeller splines. Those things chatter like crazy.

There are many yamaha's beating around with original drivelines from the 90' that have no spline issues. Its not till someone starts messing with it that the splines start striping. Either way they all make the noise the OP is describing (even if brand new) so lets get back to the original question.

Every pwc i have ever serviced makes the typical pump chatter noise. It if where splines, an outboard would make a similar noise. Hell even a stern drive has a splined coupler and they purr like a kitten on the hose (in gear or out).

Edit: Splines get sharp from a lack of maintenance. Your should grease them at least twice a season. Most people do not pull the pump until there is a problem and then its too late. Funny thing is you should service you pump bearings too. eh, has anyone ever done that?