drive shaft....splined?

[wakeboardlife]

Ok, here is my dilemma:

Recently i was out wakeboarding on a river and i hit a mystery object (never even saw what it was cause the river is so cloudy). After the little accident the boat started to shake violently whenever we would go over 5 MPH. Now my initial thoughts were that the prop was probably just knocked out of balance so I borrowed an old one from a friend to see if that would fix the problem. When we went out to try the new prop the boat didnt vibrate as bad but a little bit of shake still remained...

I"m not sure what all this means or how to check the alignment on the shaft but I was thinking about replacing everything just to be safe. I have a brand new 4 blade OJ prop handy but the problem with it is that its for the new style mastercraft shaft. I'm wondering if it would be possible to purchase a shaft to fit this prop and if it would work in my old comp.

This may be a dumb question but i have little experience when dealing with driveshafts. I'm not even sure if a bent shaft is the problem right now (could be a bent strut or bad bearings) but i am very short on cash so i can not get a professional opinion. So any help on this matter that anyone out there could provide would be great

[silvtongdvl]

Check where your shaft bolts to your tranny - I think you have broken some bolts. They can shear off when you strike something.
~S~

[wakeboardlife]

thanks, i'll go and check that out and let you know, after staring at the boat blankly for awhile i think i realize at least part of the problem, the strut bearing is worn down to almost nothing on the right side. But does anyone know if i could use the mastercraft shaft (splined, meaning with the gear teeth instead of the key stock) as a replacement for the other one?

[Salty87]

i'm sure you'd need to change the coupler to match the shaft so it depends on whether or not the coupler would fit your comp.

the shaft also needs to fit the strut and strut bushing.

have you looked at the strut and shaft? you might need to pull the shaft to check it if it's only slightly bent. while you're there, might as well put a new bushing in the strut.

how good was your friend's old prop? that might be causing the vibration you're still having.

i think if i were in your shoes, i'd get a good prop and take it out again. if your shaft and strut are ok, it will be cheaper to get a rebuilt prop than try to run that MC prop.

have you checked the pitch on that prop to see if it's even comparable? it might not work well with your boat.

pics?

[wakeboardlife]

Hey salty,

Thanks for the good info, lots of options...

Question tho, what would my options be if the drive shaft is only slightly bent, i've got pics of the strut and the new prop i used, see for yourself...

to answer one of your questions my two props are pretty much the same thing (13 x 13 original brass)

I've tried a couple times to get my pics to load to no avail. Help?

[wakeboardlife]

here is a link to some pics that i set up

http://photobucket.com/albums/b356/wakeboardlife/?sc=1

[Salty87]

first off, your prop (pic #2?) doesn't look too bad. i'd be surprised if the shaft or anything else was damaged.

next, the other prop (pic #1?) doesn't look too special. it's got some dings that would create vibrations. i'd take your old prop to an inboard dealer, doesn't have to be supra, or any prop shop and swap it out for a rebuilt. will probably cost around $100. then take your boat out again to see how it feels.

it's hard to see the shaft or strut but again, there doesn't seem to be that much damage. these nibral props take most of the beating so the shaft doesn't, designed that way. if the prop doesn't fix it, you'll have to look harder at the shaft but it's not very difficult.

good luck, let us know how it goes.


oh yeah...your photobucket account, if you copy the line below each picture, the one called Img and paste it here, the pic will show instead of the link. pretty cool.

http://i23.photobucket.com/albums/b356/wakeboardlife/NewProp.jpg

[wakeboardlife]

Hey,

Well i pulled out the driveshaft, it actually looks pretty good, (rolled it on the counter and no big humps or anything) so i figure that the problem should either be that prop or the strut. What is the best way to get out those bushings?? to get them back in?? I really dont want to drop 60-100 bucks on a removal tool, is there a way to rig it?

[Salty87]

have you found a prop shop yet? the place i use popped my bushings out in the parking lot, i dragged my boat there. it took about 3 mins....no charge. they're cheap to replace and easier to get back in.

[wakeboardlife]

One more question Salty...I forsee a problem getting the coupler back onto the driveshaft...Is there a good way to press the thing back onto the shaft?

[Salty87]

yeah, that's definitely one of the harder parts of re-assembly even with new parts.

i used a permanent marker to mark a line around the shaft where the coupler should sit when it's together correctly. it's nearly impossible to tell when you're in the bilge if the shaft has gone in the coupler far enough without a reference point.

then, i put a really thick rubber spacer between the coupler and the tranny so they wouldn't bang together, line up the shaft and slide it as far into the coupler as you can get it to go by hand.

i don't know what a shop would do at this point, but i grabbed a section of 4"x4" lumber i had laying around and a heavy sledge hammer. i placed the wood behind the prop side end of the shaft and drove it forward with the sledge. the wood is soft and will start splintering way before anything happens to the shaft. a heavy sledge will knock the shaft forward pretty easily, maybe only 4 or 5 hits. don't go too far, it's even harder to back the shaft back out a little bit...i found out the hard way on that one.

it sounds a bit extreme but really went together better than i thought it would, that's why i had to back the shaft out of the coupler a bit.

and, 2 sets of hands really help. i kept a person in the boat keeping an eye on the tranny and watching the progress.