Calling all 1992 Supra Comp Owners?

I have a really nice 1992 supra, I'm the second owner and this boat that has under 150 hours on it (making the point that the hull etc is like brand new).

I've had the boat for a couple seasons and am very curious about something. The boat takes on a lot of water and I really can't figure out how or why (even in dry weather). The auto bilge works great but it seems to dump water every couple hours even with no rain and just sitting at the dock? I triple checked my two drain plugs and made sure they had seal tape. The only other way for water to get in the boat is where the fixed prop leaves the boat bottom side?

Maybe this is normal but just wondered if anyone with this boat could comment. Thanks!!

Would you say that the bilge runs more when underway or at rest? Or does it not matter whether the boat is running across the water or sitting?

I would say it's probably a bit more when running but the bilge will still cycle quite often at rest. I can hear it going at night from my cabin bedroom. ;)

That's rather odd. My boat is considerably older and has more hours on it and it can sit all night and in the morning when I go out to it, the bilge will have a small amount of water in there if anything. I used to get a considerable amount of water when running and I sealed along the rub rail and that fixed the problem there. I'm kind of at a loss though with the bilge pump running through the night.

Thanks Ben! The rub rail, that's pretty interesting, this boat does sit pretty low in the water so that might be work checking into. At the very least I know there is some problem I need to investigate knowing yours stays pretty dry.

Bet you don't spend much time looking at the stern of your boat so here's a shot I got when I run ballast on my boat...

Attachment 9014Attachment 9015

You can see how low the rub rail can get to the water plus you have spray that runs along the rub rail. My bilge would run everytime I came off plane to pick up a rider. Now, it runs after a significant amount of riding.

Great ideas, thanks a lot guys! I'll check this stuff out once I get it back from storage next month. COME on summer, can't wait!!

What about the exhaust? I noticed in my Saltare that I was taking on water from where the exhaust flange mates to the exhaust pipe. When I took the boat apart to redo the stringers I noticed that the SuperTrapps, flange and seal was all the cause of my leak. I removed this set up and went with the flapper style exhaust.

I agree it’s amazing how much water will come in around the rudder shaft. Pull your back seat look underneath the gas tank look at the router assembly . If there’s a great big nut may be about an 1½ inch. You could tighten it about one turn and see if that helps. You might also need to change the packing that Dan spoke about. If there is no big nut to tighten you might need to change the seal that’s in the router port. Not a fun job ,it’s hard to get to. Good Luck

I'm on the rudder seal myself. There can be a small zirk fitting on the shaft which can take some grease. This grease will prevent a small seapage of water like you are describing. Is there any play on the bottom side of the shaft, lie under the boat and move the rudder from side to side and front to back. If there is play 100% your leaky....

My first guess would be the shaft packing nut. I've seen boats take on plenty of water with a bad shaft seal. $5 for a new seal. They need to be replaced almost every 3-4 years anyways.

Then rudder.

Then exhaust.

The chances of you taking on water from your rubrails is minimal versus the first three options. Possible yes, likely no.

I will agree with Haugy...I guess I didn't think about those because they are not problems for me yet. My big issue with taking on water was the rub rail but those others all sound like "better" culprits now that I think about it.

I see, I have the flapper style exhaust but I just assumed this connected (one piece) right up to the large pipes by the engine. So I was thinking this was sealed and wouldn't be a source but I will double check when the boat gets out of storage. Thanks!

Thanks haugy, you know after all these great suggestions and comments, I have a pretty good feeling it's shaft seal, this makes a lot of sense. Especially given the fact the previous owner let this boat sit in storage a lot without use. This would certainly point to seals drying out and leaking. Thanks again to everyone for the help, I'm really glad I joined this forum. Cheers!

All areas need to be looked at. Exhaust, Rutter and s,haft. Most of the time igs the shaft. Its a $10 fix so start there.

Turns out it was simply the shaft packing nut was not tight enough. I tightened it down so just a drop of water every few seconds comes up the shaft to keep it cool, problem solved in case anyone else runs into this problem.