I have a 96 Sport Nautique.

I've been getting enough water in the bilge that the auto-bilge would turn on every hour or so just sitting in a cove.

I repacked the rudder, since I can't really get a good look at it on water, due to the fuel tank. The prop shaft packing drips once every 10 seconds or so, so that shouldn't be it. The rudder repack didn't help.

I was checking under the boat and some of the sealant looked pretty bad, but I read somewhere that it's non-serviceable, so I assumed it was ok.

During troubleshooting today, I screwed in the plug and filled the bilge with about 4 inches of water. When it was at "rest", nothing leaked. When I jacked the front of the trailer sky high, and the water shifted to the stern, this is what I got:

https://www.youtube.com/watch?v=KF4-CfTKfZs" rel="nofollow - https://www.youtube.com/watch?v=KF4-CfTKfZs

I think I found my issue! Leaks that produced a steady drip from the rudder mount, and a waterfall from the prop strut would definitely fill the bilge as quickly as I was seeing it do.

So now I need to remove the mounts and re-do the sealant.

A couple of questions:

1. I'm assuming I will need to remove the prop shaft entirely to re-seal the prop strut?

2. Assuming I also have to remove the rudder, how do I go about doing that with my trailer not having the clearance to pull it out once it's free? Are there any tricks to getting the back end of the boat elevated enough? I tried dropping the front of the trailer, putting jack stands with blocks under the transom, then raising the nose as far as it would go. This did not give me enough clearance to get the rudder out.

3. It seems that 3M 5200 is the sealant of choice, yes?

Any other thoughts or pointers on getting this done? My wife is telling me to take it to a shop, but "DIY or DIE". Every project is an opportunity to learn something new and pick up new skills. This would be no exception.

Thanks!

No, you won't need to remove the prop shaft. Disconnecting the shaft at the trans coupling will give you enough room to get the strut out of the hull recess and swing the strut down for a clean up/reseal. Go 4200 instead of the 5200 just incase you ever have to remove the strut again. When you remove the strut, you will need to check alignment since alignment always starts at the strut. 

You'll probably have room to scrape the old stuff off and put some new stuff on and bolt things back up.

Another good choice for sealant would be Loctite PL Marine available at big box stores(like Home Depot or Lowes) everywhere.

It just as gooey, sticky and messy as the 3M 4200 and works equally well 

3 ounce tube is about 10 bucks and you'll have plenty left over unless you're really messy

Thanks for the tips, fellas!

KENO wrote: As far as the rudder port, I'd bet that if you do your same jacking routine, leave the rudder in the port and remove the 4 machine screws and nuts, you'll have enough working room to let the rudder and port drop down but not out. You'll probably have room to scrape the old stuff off and put some new stuff on and bolt things back up.

I go the rudder off without having to jack anything up. There was just enough room to pivot it all out out once the port was unbolted. I've got it all cleaned up, but I'm thinking of getting new hardware & larger fender washers just to start fresh. I'll wipe down the area with acetone before I apply anything new to get the best bond I can.

8122pbrainard wrote: Mark, No, you won't need to remove the prop shaft. Disconnecting the shaft at the trans coupling will give you enough room to get the strut out of the hull recess and swing the strut down for a clean up/reseal. Go 4200 instead of the 5200 just in case you ever have to remove the strut again. When you remove the strut, you will need to check alignment since alignment always starts at the strut.

This is next, since there's now more room with the rudder removed.

Is there a suggested way to get as good a baseline alignment as possible when re-installing the strut? I don't have any way to mark where the current strut is mounted, since it's all covered in sealant. And it seems like there's enough play in the strut mount to really throw off the alignment. I'd like to get it as close to aligned when I put it all back together, so there's not as much fiddling with the motor mounts. Thoughts?

And how much sealant is recommended? More is better, right? You can always clean up excess that squeezes out, but you can't add any after the fact. I was going to fully cover the recess where the strut mounts, then add some into the holes before pushing the bolts through.

The baseline for strut alignment is with the shaft in place, it should be very close to center in the log while it turns freely in the cutlass. (lubricate the cutlass with some soapy water) Support the foward end of the shaft to take the weight off it when doing this. 

You may have it on and off numerous times if shimming is necessary

Then when it's right your plan for sealant sounds good, remove it put the sealant on, along with any shims that may have been required and tighten things up and wipe away the excess