CONTINUOUSWAVE

My 2005 150 SPORT has a wet hull. I need a game plan to drain off the water.

The water entered the hull through a plate that was mounted to the floor for a pedestal chair that leaked water into the hull. The through hull drain on the transom was also leaking; it has been replaced. Both the transom and deck appear to be sound with no soft spots noted.

One option to get out water from the hull would be to remove the mounting plate to access an approximately 4-inch hole cut into the floor for the recessed base of the pedestal which exposes the foam core. This method would be slow at best, and I don't have specific knowledge as to how much area is involved with water intrusion.

Another option I am considering is installing a Garlick type drain through the transom just above the external skin of the boat at the lowest point possible and boring a channel into the foam core about 5-feet forward into the boat. This would allow the boat to gravity drain whenever the boat was out of the water.

Are there stringers in the hull that would make this method unworkable?

I am located in the cold north so work cannot proceed until the spring thaw but, I need to formulate actions now to implement once spring comes. I would be grateful for anyone's thoughts.

Note this advice is given from someone with 20 years of experience with Boston Whalers.

Note there are no stringers in a Boston Whaler.

Do not drill anything. Yet.

Take the boat and get it weighed. This will determine the degree of problem.

Understand the hull is filled with closed cell foam. Water will not migrate to a low spot. If you stand the boat on its transom water will not migrate to a hole drilled in the bottom of the transom.

The only way to get water out is to remove all the foam. This means removing the boats structural integrity

I would weigh the boat at a commercial scale. If it is less than 60 lbs higher than the published hull dry weight (listed by Whaler as 900 lbs.) I would seal the holes and go boating.

If more than 60 lbs I would:

Remove the replaced drain and assess if the transom is damp. Try using paper towels to wick moisture. Use a warm air to dry the tunnel then seal with epoxy and reinstall drain with marine sealant.

For the chair holes, enlarge holes to 1/2" diameter, use papertowels to wick moisture. Use warm air to dry foam, then fill hole with epoxy.

Reference information:

https://continuouswave.com/whaler/reference/FAQ/#Q3

Questions?

SoDakWhaler wrote:The through hull drain on the transom was also leaking; it has been replaced.

If you already replaced the drain tube at the transom, you missed the opportunity to explore for water surrounding the drain hole. Or perhaps you did that, found none, and there is no need for concern there.

SoDakWhaler wrote:...I am considering is installing a Garlick type drain through the transom just above the external skin of the boat at the lowest point possible and boring a channel into the foam core about 5-feet forward into the boat.

Creating a long void in the foam in the Unibond hull is probably not a good idea. The foam is a structural element of the hull.

I thank you for the replies to my request for info. I didn't go into detail in my original description and will now.

When I removed the transom through hull fitting, I did note it was moist. Almost directly below the fitting I had a acrylic type board attached to the hull that has my transducer mounted to it. I pulled the screws from this acrylic board and had about a pint of water slowly drip out of the screw holes over a period of several days and no additional dripping of water was noted.

I also noted this board had not been installed water tight and was an additional source of leakage into the hull. This acrylic board is currently still off the boat and original demount date was in October. After about a week of open air drying of the through hull fitting hole on the transom, I coated all the internal wood surfaces of the through-hull cut with 3M 5200 adhesive and then also applied same to all external surfaces of the fitting as well as the ribbed section of the fitting used to force fit each end of the fitting. I had significant ooze on both external and internal surfaces around the fitting which I cleaned up per instructions posted by 3M.

I believe my next course of action will be to demount the pedestal on the boat, and I will have full access to the core exposing the foam. To accommodate the pedestal base their is a 4-inch hole in the internal boat deck and foam has been removed to the bottom skin of the boat to make room for the subsurface portion of the pedestal base. (This area held about 1-inch of water when I originally worked on it.) I can then wick up any noticeable water present as well as keep the area open to the air for about a month for continued de-watering as I see necessary. Hopefully the area dries out and I can then close up the area, again using 3M 5200 adhesive caulk.

I am debating if I will remount the pedestal or if I can clean up the floor sufficiently, instead install a circular access hatch for future monitoring of water in the hull. I again thank each of you for responding.--Jim

To accommodate the pedestal base their is a 4" hole in the internal boat floor and foam has been removed to the bottom skin of the boat to make room for the sub surface portion of the pedestal base.

Oh crikey someone has done a seriously stupid thing. This is the opposite of the correct method of installation.

NO 5200 on a Whaler, EVER! This is an adhesive first and a sealant 2nd. It is not designed for what it is being used for. Blame the morons in the marketing department of 3M. They push 5200/4200 cause its more expensive than their decent marine sealant.

Air dry the hull cavity for as long as practical. When ready. Use heat, hairdryer on the void to get it dry.

Fill the hole with 2 part 4lb marine expanding foam.
Apply woven fiberlass fabric with overlap onto the existing floor.
Seal with epoxy.

Read this:

Repair the Whaler way: https://www.continuouswave.com/whaler/reference/whalerRepair.html

SoDakWhaler wrote:....I coated all the internal wood surfaces of the through-hull cut with 3M5200 adhesive....

I advise caution with using 3M5200 Adhesive as a sealant. The 3M5200 product is known to be an extremely strong adhesive, and any components adhered in place with 3M5200 may be nearly impossible to remove in the futurewithout destroying the component or part of the hull.

The 3M5200 cure time is lengthy, and a full strength cure may take a week. A lower-strength adhesive with a faster cure time is 3M4200FC. But even 3M4200FC might have too much adhesive strength.

If you want to seal off the interior foam sections of a through-hull hole passage, consider using epoxy resin. The epoxy resin will be waterproof. Once it is cured you can restore the original diameter of the hole with a circular sanding tool just some sandpaper and your finger.

In a c.2004 Boston Whaler boat the through-hull fittings might be plastic instead of brass. Please describe the material of the the through hull fittings on your boat.

The thru hull fitting used was a two piece plastic fitting with the interior portion sliding along a ribbed surface into the external portion. Is was easy to accomplish and was a direct replacement for what was on the boat originally. Your info on the 3M 5200 amazes me as my local boat dealers specifically called out using it over any other sealant/adhesive available on the market It has been my intention to actually demount every attachment on the boat held on with screws and remount after applying 3M 5200 to ensure a watertight attachment. Now that I have found to have a water logged concern, I want to eliminate any and all ingress points of water that are possible. What type caulk or adhesive would you recommend rather than the 3M 5200? Whatever was used on my boat originally was not effective as I am seeing some powdering away of the caulking material as I remove attachments. Another question I have is what do you think of my thoughts on removal the additional pedestal all together and replacing with the circular access hatch as a 4" hole is already present and I need to deal with it somehow? I would have about 6 holes about 1/4 " to plug which shouldn't be an over hard venture, but I would gain access to continued dewatering of the hull until I am satisfied it is truly empty as well as provide an access point to monitor for any future problems with water invading the hull. I don't want to sound anal about getting this concern under control, but my Whaler is my baby, and I have been driving a Whaler since 1971. My first Whaler was while in the USN and was a modified 17' Montauk type hull which the U.S. Navy called a PBL, (Patrol Boat Light).