water in bilge

[10blade]

Hello all!

The short version of my question goes like this: when does one diagnose a leaky stuffing box? Should the shaft log be turning? or idling? or neither?

The long version goes like this: On the maiden voyage with my 17 foot glass ski boat, I noted quite a bit of vibration at moderate speeds. After re-trailering the boat, I noted that the shaft log was bent. Bummer. I looked around this remarkable forum for advice, and decided to replace the log. The change went smoothly enough (thanks classicboatconnection.com for some mid-procedure help!) I did not replace any material in the stuffing box...maybe that's the problem? Anyhow, the next time on the lake---no vibration, beautiful. I've had it out 6 or 7 times, no issues, so it seems.

Which brings us to the water in the bilge bit. A typical outing in the boat involves 4-5 hours on a lake, manual bilge pumpage, and re-trailering. The bilge pump has turned on automatically while on the trailer (twice), and once it came on while approaching the dock. I have no idea if any of this is normal. It doesn't seem to be getting worse. But I have no baseline (or pre-change of shaft log) experience with which to compare.

Thinking it may be excessive, this past weekend I searched for a source. Now, I know that water leaks in from the aft side rub rail areas while banking at high speed, that I've seen. But the time that the bilge pump went on automatically while approaching the dock...that time there was no "high speed," we had been out watching fireworks. So yesterday I started it up (I was kinda hoping it'd be something simple like a cooling system drainage stopcock), removed the engine cover, the planking between the engine and the rear seat, and the rear seat. No obvious leaks. No dripping, no spraying, nothing.

Should I have a good look while the boat is moving? Since I messed with it, I need to rule-out the stuffing box/shaft log as a source. Is it normal to manually pump the bilge EVERY TIME you take your boat on the water? Is it normal for it to occassionally go on by itself without any "spirited" driving? Is there anything, anything at all "normal" when you're speaking about a 40 year-old boat?

That's it.
Love the boat.
Thanks,
10blade

[Al Benton]

If you had a leak at the stuffing box I think it would be obvious whether the shaft is rotating or not. What it might be is the shaft log itself. When moving it may actually be removing water like a self bailer would, but when stopped or moving slowly the water comes in enough to start the bilge pump. It's a thought.

Al

[quitchabitchin]

Nate,

All of the 1969 Ski Boats leak between the hull and deck in sharp turns unless they have been resealed. I spoke to a former dealer who sold them new in 1969 and said he fixed almost every one under warranty in the early 1970's. If you remove the panel over the shaft log while the boat is in gear, you will see it drip. There are different schools of thought on how much or often it should drip. Some say one drip every 5-10 seconds, some say no drips at all. Our '69 takes on the most water around the exhaust tubes, between the copper pipes and the chrome exhaust flanges. When you sit in the water, the exhaust is right at water level and even under water with a couple of adults in the back of the boat. If the packing around the exhaust pipes is old or faulty, you will get water in the bilge. Good luck and I'm glad to hear it is running well, mine is running like crap right now and between selling a house, renovating a new house and trying to move this weekend, I haven't even seen the water in several weeks.

[10blade]

I think you may have something with the exhaust area being the culprit. I plan on resealing beneath the rub-rails when I replace them this winter and I'll reseal around the exhaust too. I've heard good things about 3M 5200 and 4200. Hey, while I have your attention, it's clear that my current rub-rails are not the original. Of all the replacement rails I've found, it would seem that the ALS-21 version at www.rubrails.com/aluminum_solid.html would work the best. What do you think? They would sort of wrap around and cover the seam between hull and deck. Oh, and one last thing: what's your rudder look like? I'm serious. Mine's a bit askew. Looking at the back of the boat, it's cocked a bit to the left. I removed it, gave it a good looking over, and, as far as I can tell, it's MEANT to be that way. It's a little thicker on the left, like reinforced, and there's no damage.
Sorry to hear that your boat is running poorly. I guess that could happen to any of us at any moment. Thanks for the friendly advice.
Nate