While riding yesterday I felt a new vibration. From a dead stop if I punched the throttle I felt a slight loss in power.if I revved up slow it was much better but full throttle still felt weak with a high free vibration. After pulling the ski out I checked the pump for any junk. Nothing in the pump (besides a small fish in the intake grate!!!). While moving the prop I noticed a small play in the shaft. Its not a lateral play but rotational instead. I can grab the shaft a d rotate it left and right a few degrees. I don't think this is normal I have never felt it before. Checked on another ski and it has no play at all. What could cause this, and is it the cause for my apparent lack of power??
slight play in drive shaft??
- Thread starter ticega306
- Start date
- Location
- Santa Barbara, CA
I am not a technician, but in my experience it could be the splines on the drive shaft where it meets the hull or play in your coupler. Check the rubber dampener (easy thing to do).
stanton
High on jetskis.
- Location
- atascadero,ca
your pump bearings are shot.
oxnard111
Creative RE Purchasing
- Location
- so Cali, Ventura/Oxnard area
worn splines are caused by improper alignment of any portion of the drive train (engine, midshaft, or pump). Also with all the on/off of the throttle that is so common when riding standups, the splines just start to wear.
If you are going to replace splines you must do both the mid shaft and drive shaft at the same time other wise one will just wear the out very quickly. Both SuperJett and I can attest to this.
If you are going to replace splines you must do both the mid shaft and drive shaft at the same time other wise one will just wear the out very quickly. Both SuperJett and I can attest to this.
ok if i replace pump bearings, and leave the shaft and midshaft as is with the slight play (assuming worn splines) how does that sound. I'll recheck my engine alignment cause it was most likely the cause (replaced engine mounts about a month ago). Can i keep running it with the slightly worn splines. until i get a new shaft/midshaft. New years weekend is a big riding weekend here and i don't want to miss it. I doubt ill have time to have a new shaft/midhsaft delivered!!
oxnard111
Creative RE Purchasing
- Location
- so Cali, Ventura/Oxnard area
You need to pull the pump to confirm that the bearings are truely shot. The splines will last a while longer. Just ride it until after your big weekend.
TB
NOTHING IS EVER PROMISED
- Location
- Grand Rapids, MI
i read the title and was gnna come on and say to change your u jints....guess i forgot what frum i was on :dunce:
SXIPro
JM781 Big Bore
- Location
- Here on the 'X' mostly
My vote is for the midshaft bearings. That is just what I experienced moments before I pulled the ski ashore and found ball bearings in the bottom of the hull. Never a good sign. :smashfreakB:
stanton
High on jetskis.
- Location
- atascadero,ca
oops i misread, your midshaft/drive need replacement.
so final verdict... as per my assumtions
heavy vibration from completely busted prop (pics to come soon) coupled with slightly misaligned engine resulted in worn out midshaft bearing. mishaft and drive shaft splines took a good beating (hence slight play). pump bearings are still perfect.
parts to be replaced:
midshaft
midshaft bearing
drive shaft
prop
all adds up to a pretty penny!!
heavy vibration from completely busted prop (pics to come soon) coupled with slightly misaligned engine resulted in worn out midshaft bearing. mishaft and drive shaft splines took a good beating (hence slight play). pump bearings are still perfect.
parts to be replaced:
midshaft
midshaft bearing
drive shaft
prop
all adds up to a pretty penny!!
oxnard111
Creative RE Purchasing
- Location
- so Cali, Ventura/Oxnard area
yup... prop might be salvageable. but we'll see when you post pictures... IMPROS can do wonders.
Best to look for a good condition midshaft assembly, being sure to ask the seller to inspect the female spline section closely.
Good luck finding just a drive shaft alone that has good splines. Maybe one of the FX-1 guys doing a 144 pump conversion can hook you up. They don't need the shafts on from the 144 pumps.
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oxnard111
Creative RE Purchasing
- Location
- so Cali, Ventura/Oxnard area
Which year ski are you working with?
best OEM prices for a RN I have found are:
Drive shaft - $195
Mid shaft - $109
Full mid shaft bearing rebuild kit - $62
http://www.yamahasportsplaza.com/pages/parts/viewbybrand/default.aspx
best OEM prices for a RN I have found are:
Drive shaft - $195
Mid shaft - $109
Full mid shaft bearing rebuild kit - $62
http://www.yamahasportsplaza.com/pages/parts/viewbybrand/default.aspx
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oxnard111
Creative RE Purchasing
- Location
- so Cali, Ventura/Oxnard area
dremel tool??? haha j/k
those prices on the website i listed above are going to go up after the 1st... i got an email from them a couple days ago saying they have to raise their rates. Just FYI.
those prices on the website i listed above are going to go up after the 1st... i got an email from them a couple days ago saying they have to raise their rates. Just FYI.