Replacement Prop Shaft

[Juice75]

I'm replacing my snapped prop shaft and my coupler (it's a little worn). My question is, if I'm replacing the shaft AND the coupler, do I have to stick with a tapered shaft? Or can a get a standard non-tapered shaft and the matching coupler?

The reason I ask is I can get a shaft that's not tapered for about $100 less than a tapered one. It seems like if the coupler matches the shaft, and the shaft is the right length and diameter, and the coupler holes match the holes in the transmission plate, then it shouldn't matter if it's tapered or not. Or am I missing something here?

By the way, my boat is an '89 Supra Comp.

[Brian Raymond]

Yo Juice, I would stick with OEM. When purchased through the dealer or Skiers Choice, you will receive the shaft with the coupler already pressed and mounted on the shaft. This means the shaft and coupler have been installed by the vendor and has had the coupler face, milled and balanced, while on the shaft. The downside is, you have to pull the motor in order for proper shaft replacement. The upside, your engine alignment will be tried and true, you will not have after-install vibrations, (which are prevelant in press on coupler to shaft installs, not being balanced). This will reduce shaft log wear and strut bushing wear in the long run. To save the headaches and future issues, I would stay OEM. Brian Raymond

[Juice75]

Hey Brian - I would love to go with the OEM stuff, but pulling the engine is not an option for me right now. I'm looking at the A.R.E shafts from www.SkiDim.com. They're a little pricey, about the same as the OEM stuff, but the install is supposed to be easy.

I can get a non-tapered shaft and coupler for about half the price, that's why I was asking if it mattered. I'm closing on my new house next Wednesday, so I'm trying to save as much money as I can and still have a reliable boat. :)

[KenG]

Juice75,

A.R.E. drive shaft systems are an excellent option to OEM. Compared to OEM, the A.R.E. system is much easier deal with for both installation and removal of the driveline. Installation can be done with the engine/transmission in place.

With a properly installed A.R.E. drive shaft system, you will not have any vibration issues, at least not from the drive shaft. If I remember correctly, the TIR specifications for an A.R.E. drive shaft is equal to or tighter than OEM.

To aid with the drive shaft installation, A.R.E. offers a couple of special tools, although the job can be done without these tools.

I would suggest replacing the strut bushings since you will have everything apart.

Also, if you want a dry bilge, now is the time to get rid of the stuffing box and go with a PSS shaft seal.

Finally, be sure to check the engine alignment and adjust as needed; this is crucial for proper drive shaft installation and minimal vibration. I do not know what broke your drive shaft but incorrect alignment can cause this type of damage.

As far as going with a single or double taper drive shaft, I cannot offer advice. Your stock setup is probably a double taper, but if Skidim says a single taper will work, then I suppose there is no reason not to use it.

Overall, my advice will not save you any money, but it will make for a very good drive line set up. Howver, you might be able to save a little money by dealing directly with Elbert’s instead of going through Skidim, but then again, Skidim is a good source for technical advice.

--KG--

[Juice75]

KenG - thanks for the reply. I actually ordered all the parts I need from SkiDim yesterday. I went with the A.R.E shaft system. It was a couple dollars more than the OEM setup, but not having to pull the motor to install the shaft was worth it. And this way I know I have a quality part that should last the life of the boat.

My shaft broke because the strut was REALLY bent, and I didn't know it. Judging by the strut bushing, it's been bent for awhile. The strange part is that the boat never vibrated...not even a little bit. I guess the strut was keeping so much pressure on the shaft that is wouldn't vibrate. To give you an idea of how bad the strut was bent, my rudder is offset to the right, so the shaft should pull out to the left of the rudder. When I took off the lower part of the drive shaft, it came out on the right side of the rudder! So needless to say, I ordered a new strut with bushings as well.

With having to buy a shaft and strut, I'm going to have to wait on the PSS seal. Just don't have the money left over. But I did buy new rope seals, and I'll repack the shaft seal during the install.

Thanks again for everybody's advice. I'm hoping to have it all back together and be back on the water by Memorial Day weekend!

[DKJBama92Mariah]

Good luck with the install Juice,

If I may, i'd like to point out one thing before you get started because i learned the hard way. Dont just slap some sealant on the strut and bolt it up. I did that, and come the next day and time to install the shaft, and the strut did not line up with the stuffing box. After alot of profanity and scraping of sealant, i had to redo the job. I handled it by barely screwing the nut onto the stuffing box. I then put the strut into the shaft AND THEN pushed the shaft into the boat through the box. At that point, i then reapplied the sealant (3M 4200) to the strut. It doesnt take as much as you would think, i learned the messy way the first time. I would say... think about the amount of sealant on a water pump gasket (on a car or truck) and make the bead of sealant a little thicker. In addition, put a WIDE bead in the middle of the mounting plate. Also, I squirted a large marble sized gob up into each of the mounting holes. Once you do this, you can mount the strut, preferably with a helper inside the boat. Just make sure as you're tightening the bolts that the shaft looks centered in the hole where it enters the boat. Good luck, and about the only thing that gets that sealant off your hands, arms, face, hair, etc. is paint thinner or gasoline. Needless to say, my gf was asking what the #e!! is that smell, even after a 30 minute shower.

Good luck and hope your install goes smoother than mine.

Cheers,
DKJ

[Juice75]

DKJ - that's hilarious!!! Thanks for the advice. I would have done the same thing you did; mounted and sealed the strut first. I guess I just assumed the mounting holes would line it up right. All my parts should be here by Tuesday at the latest. I'll give an update once I'm done....or if I get stuck.

Oh, and I'll definitely were rubber gloves. I've learned that lesson the hard way toooo many times. ;)

[DKJBama92Mariah]

Just to share, here's a pic of my old strut after i got it off. I'm still not sure what i hit, it kinda makes me curious if a california redwood could possibly end up in a river in Alabama.

Cheers,
DKJ

http://img.photobucket.com/albums/v55/dkjpika/Boat/BentStrutPic.jpg