All of these compartments include a drain hole to allow any water that gets into them to drain out. But instead of the drain hole being located in the compartment floor, it’s located on a side wall, with the lower lip of the drain hole one inch off of the compartment floor. This means that when water gets in the last inch of it has no means of escape. It sits there, eventually getting slimy and gross. In winter, if it gets cold enough where you live, it freezes, the expanding ice potentially putting pressure on the compartment seams. Not good design.

At this point drilling holes in the floors of these compartments is no solution as it would have them draining into the bilge, something I do not want. So the best option I can figure is to displace that last inch of water by putting in inserts that in effect raise the floor of the compartments. It has to be something that is durable, won’t rust, rot, or absorb water, float, or cause discoloration. Some possibilities:

• Synthetic deck “wood”
• Acrylic sheets (like they use for cutting boards)
• PT
• Solid rubber mat

Any other ideas?

So I decided to do a comparison of shipping rates. I searched for the same item on a dozen or so large boating supply web sites. (If a site didn’t have the exact item, I chose a similarly priced one so I could still compare their shipping rates.)

What I found was  a range in shipping fees from free shipping (Overtons) to $16.18 from Go2 Marine ($11.18 shipping + a $5 small order handling fee).  And Go2 Marine might not have been the highest: While Boat Owners Warehouse stated on their shopping cart there would be an $8 handling fee, I never got the actual shipping cost as the site would not show it until I entered my credit card info first (somethingI declined to do).

One other thing I dislike when shopping online: having to gp through checkout before you can find out what the shipping fee is. Fortunately, many sites include a calculator that lets you see the estimated shipping as soon as you put an item in your cart. Just punch in a state and zip code. Others though make you fill out all of your personal information first. And Boat Owners Warehouse, unbelievably, also wanted my credit card number before it would quote a shipping fee.

The Wahoo! hull: What’s in there?

Basic to understanding the design of a Wahoo! is knowing what’s going on insider the hull. Some key points:

Wahoo! hulls contain foam. This helps with buoyancy of course. Boston Whaler hulls are foam “filled.” The “filled” part means very bit of the hull interior is filled with spayed-in foam. This not only maximizes buoyancy, it also in theory keeps water out of the hull because there’s no literally place for it to collect. But there are a few potential drawbacks to this design. For one, because there is the assumption of no water ever entering the hull, Whaler hulls do not have a drain plug. That means if somehow water DOES manage to get in there, there’s no easy way to get it out. A second concern is that over time the hull foam may begin to absorb water, not unlike a sponge. The water could come from the outside or it  could come from condensation inside the hull. Either way, as the foam absorbs water it takes on weight. That causes handling problems. And over time the moisture can cause the foam to break down.

Distinct from Whalers, Wahoo! hulls are foam “lined.” The “lined” part means that the top, sides, and bottom of the hull interior are coated with blown-in foam but there is an air cavity in between. Also the Wahoo! hull includes a drain hole in the stern. The advantage of this design is that the cavity allows the interior foam and stringers to “breathe”; that is, the ability to dry. And any water that does get into the hull can be drained. The downside, compared to the Whaler design, is that with less foam comes less buoyancy, and the air cavity allows water a place to collect.

Cutaway showing foam liner and air cavity.

The original Wahoo!s from the mid 80s design did not include a bilge pump. Since that time 25 years’ worth of Wahoo! owners have wondered why, because water certainly finds its way into Wahoo!’ bilges, as it does with any other boat. It’s not immediately clear what the the absence of a pump meant from the manufacturer’s perspective. Maybe it meant the company  had a misplaced faith that water wouldn’t get into the bilge. Or maybe it meant they assumed that most Wahoo!s would be used as trailer boats whose drain plugs would be opened after every use. Or maybe it was simply an attempt by the company to cut costs and leave it to customers to add their own bilge pumps. Whatever the source of the initial decision, it was not adequate. Within a several years Wahoo! brochures began mentioning an “optional” bilge pump.

How water gets into the hull

So does your Wahoo! need a bilge pump? First, let’s talk about the ways that water can get into your bilge. Leaving aside leaks in the hull exterior (but all the more reason for a bilge pump), you have:

• Condensation (aka “hull sweat): If you store your boat in the water, condensation will form inside the hull. The amount will vary based on temperatures but can easily result in a gallon a week of water in the bilge.

• Cracks in the deck drain system: The Wahoo! deck drain system (discussed in this post) consists of a series of deck flanges and below deck PVC tubes. It’s quite common for these to develop cracks that allow water into the hull.
• Power and steering cable deck port: On many Wahoo!s the power cables from the battery and the steering cables from the engine pass into the hull and then up into the console through a hole in the the deck. This deck hole can allow quite a bit of water in.
• Access ports: Access ports, either original or after market, are notoriously leaky.
• Other screw holes or cracks: Lastly, any screw hole in the hull, if not properly caulked, can allow water to leak in.

All of these things together conspire to allow quite a bit of water into you hull. Water is especially good at finding its way in when its got some force behind it, such as wind-driven rain or when you’re hosing the deck. And given the relatively small size and weight capacity of Wahoo!s, and that a gallon of water weighs seven pounds, it doesn’t take much to affect performance.

Adding a bilge pump

So to the question of whether your Wahoo! needs a bilge pump, I say the answer is, yes, absolutely. Even if you keep your boat on a trailer, the added safety and security that a bilge pump gives you make it well worth it. The installation is easy and inexpensive. I would not waste time considering a manual pump–put in an electric one and be done with it.

Locate the pump in the spot shown in the diagram above, at the rear of the bilge along the keel. This is the lowest section of the hull and where all water will run to. Most Wahoo! tri-hulls come with a five inch access port in the center of the stern through which you can install the pump. If  yours does not include an access port you’ll need to add one.

Here are a few notes on the pump I installed in case it’s helpful to anyone. There are certainly other ways to do it.

• I chose just about the smallest pump possible, a Rule 360. It fit easily through my existing access port and its capacity in more than adequate for my 16.2 Striper.
• I chose not to install an automatic float switch. But I can get away with that because the marina where I keep my boat is ten minutes from my house. So I can run over there any time to turn on the pump. If I had to leave the boat unattended for days or weeks at a time I would add a float switch or one of those chip driven pumps that cycle on and off checking for water.
• For mounting the pump, I did not want to screw into the hull. One alternate mounting method I read called for gluing in a piece of marine grade plywood and mounting the pump on that. But I decided that was overkill. Plus it would have raised the pump up 3/8 to 1/2 an inch from the bottom, allowing that level of water to sit unpumped in the bilge. The simpler solution was to apply some 3M 5200 directly to the bottom of the pump’s basket and glue the basket right to the bilge floor. In 10 minutes I had a well-fastened mount that isn’t going anywhere.
• The hose I ran it straight up and out of a hole I drilled in the access port cover. Like the pump I installed in the deck sump basin, the bilge pump drains into the splashwell.

Rule 360 bilge pump.

Hose from bilge pump exists through hole in access port cover and drains into splashwell..

A one pump system?

Just as I was finishing this post I wondered whether anyone had ever configured his Wahoo! so that a single pump handled both the above and below deck drainage. You could achieve this pretty simply by installing a pump in the bilge and then drilling about a  one inch hole in the bottom of the deck sump basin. That would dump all water that enteredd the boat into the bilge. It seems like a bad idea for a few different reasons, but man if anyone has ever tried it I’d love to hear how it went.

More reading

Here’s a little more reading on the subject:

http://www.thehulltruth.com/boating-forum/96775-16-wahoo-water-hull.html

(Note: in this message thread Monstawhala states that the top hole in the deck sump basin drains into the bilge, and that both stern compartments also drain directly into the bilge. That is wrong. The stern compartments drain into the sump basin via the aforementioned top hole in the sump basin.)

I’ve been told that in most US states the law is that any vessel run aground and abandoned by its owner, even if just for a short time, can be claimed by anyone with an aim to do so. Even if this is correct in practice it’s probably not that easy. There must be papers to file and legal hoops to jump through. This is, after all, America. In this particular case I suspect that the owner actually abandoned the boat even before it broke its mooring, as there’s been no attempt to retrieve it and from the day it washed up it had a look of neglect.

I stopped off to take a closer look at it a few times. And apparently I wasn’t the only one. Because even if no one is interested in the hull, for sure bit by bit scavengers have removed pieces of it: the anchor and lines; compass; deck hardware; life vests; ring buoys.  It’s reached the point where there’s not much salvageable left outside of some minor hardware.  I scraped some sand away and discovered Doel Fins on the motor. Just so happens I was planning on fitting my Wahoo! with Doel Fins this year.

This post will be about the Wahoo!’s above-deck drain system. Specifically it will be about the self-bailing deck drain system employed by most smaller Wahoo!s, whereby water from the deck is designed to exit out of a scupper in the stern. I may not get all the facts complete or correct the first time. So if you are are a Wahoo! owner past or present and have corrections or additional info, please add a comment or send an email. I’ll continue to update this article as necessary.

The self-bailing design concept

Smaller Wahoo!s have a deck draining system that is designed to be self-bailing. The idea is that, when underway, any water that accumulates on the deck, be it from rain, spray, waves over the gunnels, or whatever, is designed to run to the rear of the boat and collect in a small sump basin located just inside the stern. A scupper connects the basin to the outside of the boat. Gravity from the boat’s forward motion forces water from the sump basin through the scupper and out of the boat. (Note that it is only the Wahoo!’s deck only that is designed to be self-bailing, not the hull interior.)

Theoretically, the benefits of this self-bailing design include:

• No need for bilge pumps (which can fail). The system takes care of itself.
• The boat’s bilge does not take on water because the self-bailing deck drain precludes water ever getting down there.
• When the boat is at rest, some water comes in through the sump basin scupper. But this water levels out and never goes above the top of the basin.

The components

These are the components of the system (that is, the related parts designed to make it work), listed from front to back:

• Forward compartment drains: Wahoo!s, depending on the model, have several above-deck compartments. An anchor storage compartment in the bow is common to many models. Some also have a combination cooler/seat positioned just forward of the steering console. Both of these compartments have drainage holes that allow any water they take in to drain directly onto the deck.
• Sump basin conduits: Some Wahoo!s had a solid fiberglass bench seat that spans the width of the cockpit (in some models the seat contains a built-in fuel tank, in others, a cooler, and in some both). Since the seat blocks water attempting to run to the rear of the boat, these models include a conduit…a hole in the deck just forward of the seat that funnels water into a pipe that connects to the sump basin. Also, common in many models are two small compartments on either side of the stern. Wahoo! literature describes them as battery storage, or as optional coolers or live wells. it’s also a popular location for a fuel/water separator. Both of these compartments have drain holes that drain into the sump basin.
• Sump basin: As stated, Wahoo!s with the self-bailing system includes a sump basin in the rear of the boat just inside the transom. Water is designed to drain into this basin and then exit the stern through a one inch scupper.  The basin varies in size with model. In my 1987 Striper 16.2 the basin is 18 inches long by 4.5 inches deep by 8 inches wide. Its capacity is about 2.5 gallons.
• The scupper: The scupper is simply a tube that connects the sump basin to the outside stern of the boat. It consists of a through-hull PVC pipe (approximately six inches long and one inch diameter) with flanges at either end. Important to note: it is located below the water line.

Drain conduit forward of bench seat

The sump basin looking toward the bow. The hole is the conduit that drains the deck area forward of the bench seat.

The sump basin looking to the stern. The top hole is the drain for the two rear compartments. The bottom hole is the scupper.

Years and models

I don’t have a list of the years and models that use this self-bailing system. A 1995 Wahoo! brochure that covers 19 foot and up models makes no mention of it. Yet I’ve spoken to owners of 2100 CCs who said their boats have it. All of the 16.2/1650s I’ve seen have it, as do all of the 1750 Offshores I’ve seen.

Problems with the design

While the self-bailing system may have been forward-thinking, in practice there are a number of issues with the design:

• Most people simply don’t trust it. They are not comfortable with the below-waterline location of the scupper. That location means water enters the boat through the scupper when the boat is not underway.
• People do not like wet feet. Even if you’re OK with some water entering the sump basin through the scupper, that water tends to slosh up an around out of the basin meaning the rear of the boat is usually wet.
• Contrary to Wahoo!’s implied claims, there are plenty of ways for water to enter the bilge. I’ll discuss this in detail in a later post on the below deck drain system. But obviously water in the bilge, if not dealt with immediately, can cause major handling problems, as well as rotting the stringers and transom (Wahoo!s do use wood in their transoms, in case you were  wondering). There are several ways that that the self-bailing deck design can contribute to water in the bilge:
  • Cracks in the flanges or PVC tubes that drain the forward and rear compartments.
  • Cracks in the flanges or PVC tubes that channel water from the deck to the sump area.
  • Cracks in the scupper’s flanges or PVC tube.

Owner solutions

Different owners deal with the issues presented by the deck drain system in different ways, depending on their their comfort-level with the original design and whether or not they keep their boat in the water. Some options:

Solution 1 – Use it as is (no modifications): This could work fine if  you 1) Don’t store your boat in the water, and 2) Don’t mind getting your feet wet. This was the original design for the boat. In theory it should work even if you DO store your boat in the water. However few owners I’ve spoken to choose this route, regardless of where they keep their boat.

Solution 2 – Install a one-way scupper adapter. This is a flap that allows water to exit the scupper but not enter it. This solution could work fine if you 1) Don’t store your boat in the water, and 2) Don’t want your feet wet. The one-way adapter is installed on the exterior side of the scupper and opens to allow water to escape when underway but otherwise prevents water from coming in. This solution won’t work well for boats stored in the water because it won’t allow rain water to escape. Here’s an example of a scupper adapter.

Solution 3 – Plug the scupper when using the boat. This solution could work fine if you 1) Don’t store your boat in the water, and 2) Don’t want your feet wet, and 3) Typically don’t take on more than a few gallons of water topside when using the boat (and for times you do you could always just bail the sump basin). This was how the previous owner of my boat used it. Prior to each launch he installed a plug on the inside end of the scupper (plugging the outside makes even more sense). At the end of the day when the boat was pulled he removed the plug and it stayed out until the next launch.

Solution 4 – Plug the scupper and add a bilge pump to the sump area: This is the approach most Wahoo! owners who keep their boat in the water take. Plug one or even better both ends of the scupper and install a small automatic bilge pump inside the sump basin. This solution should address any above-deck water issues…provided the pump doesn’t fail!

My Solution

This is not a suggestion to do as I did but a record for what it’s worth. I store my Wahoo! in the water in a slip. Like a lot of owners, I am not comfortable with the self-bailing system. Specifically, I’m not comfortable with the notion of water entering the scupper when the boat is at rest. And I have concerns that it won’t drain properly during rainstorms–all it takes is a leaf blocking the scupper and your boat fills up with water.

So my solution was to plug the scupper and add an automatic bilge pump to the sump basin. To date I’ve just plugged the inside end of the scupper but next season I’ll plug the outside as well. (Why let water into the scupper where it could potentially leak into the hull?) For a bilge pump I installed a Rule Mate 500. That’s actually a lot more pump than the space requires. I chose it mostly because of its low profile (which allows me to keep the wooden lid on the basin)  and because its float switch is A) built in (I didn’t want to have to install a separate switch), and B) float driven rather than chip driven (hopefully less drain on the battery).

The hose from the pump I have draining into the splashwell. In order to keep the original Wahoo! teak lid on the sump basin, I would have had to drill a new hole in it (to allow the hose to pass through). But I really hate the idea of permanently altering a part that is no longer available. So I bought some 3/4″ x 3″ oak from my local lumber yard and fashioned my own slatted lid to the sump basin. It looks good and I have no problem drilling holes in it to my heart’s content.

The sump basin of my Wahoo! with a Rule Bilge Mate 500. The pump drains into the splashwell.

The sump basin with my homemade oak lid. I think it cost me $5 to make.

End Notes

So that’s a pass at explaining the Wahoo! self-bailing deck drain. It doesn’t answer everything yet. For example, I’d like to understand why the sump basin scupper was designed to be below the water line. Was that the only place it could go? Or was there a specific advantage to placing it there? Again, if you have questions, thoughts, information, or corrections please share them with your fellow Wahoo! owners.

Here are a few links to online discussions where you might find more info:

• http://www.thehulltruth.com/boating-forum/210758-wahoo-boats-3.html
• http://forums.iboats.com/showthread.php?t=526189

Next up: an attempt to explain the Wahoo! below deck drain system (a.k.a., “And here I lost my mind”   ).

So if the decals  on your Wahoo! are faded, peeling, or otherwise messed up, replacements are available. How cool is that? Prices ranged from $40 to $60 for a pair.

Two sources:

• vinylapproach.com (three different styles)
• greatlakesskipper.com (just the one pictured at right)

Paperwork Storage:

As proof the afore-mentioned levies have been paid, I keep the following documents in these locations (with copies of each at home):

• Boat Registration: On boat. (Required by law.)
• Trailer Registration: In towing vehicle. (Required by law.)
• SeaTow Card: In wallet. Also keep copy on boat.
• Freshwater Fishing License: In wallet
• Saltwater Fishing License: In wallet. Also keep copy on boat.

Finally (finally!) in the first week of January got the boat tarp/cover fixed on in such a way that it won’t blow off in a high wind or cave in and pull loose  after a heavy rain/snowfall. Up to this point I had the tarp tied with sash cord. But a good rain would load the top of the cover with water causing it to belly down into to boat. This in turn would stretch and loosen the sash cord, and then the next really wind day would just lift the whole thing off. I solved the bellying issue by cutting a bunch of wooden slats to the width of the boat and then laying them atop the gunnels (plywood would have worked too but I figured that’d be heavier and more awkward to put on and off). I solved the loosening problem by doing what you’re supposed to do…affixing the cover with heavy duty bungee cords.

The battery is still in the boat, instead of down in the basement on a trickle charger like it should be. I wanted the option of still being able to raise and lower the motor. But now that we’re into the truly frigid months here in Massachusetts it’s time to put it where it belongs.

Tasks for the month:

• Get that battery stored.
• Gearcase Screw: When I went to change the gearcase lube last fall, I couldn’t get the top screw for the gearcase loose. It was frozen and the screwdrivers I had were in danger of stripping it. Just bought a larger screwdriver at Home Depot (the bigges they had…I’ve seen swords smaller than this thing) and will take one more crack at it. Maybe the cold will have caaused the metal to contract enough that it’ll loosen more easily. If it still won’t budge it’ll have to wait until spring.
• Boat and Trailer Paperwork: I am habitually late when it comes to certain forms of paperwork…most especially registrations, inspections, excise taxes, and things of that ilk. Between the trailer and the boat, I still don’t have a clear list of what needs to get filed/paid for every year. AND in the off-season I picked up a second, smaller boat that needs to be dealt with as well. And then there are fishing licenses, Seatow membership fees…creating a list of this stuff seems like a good way to get organized.
• Safe Boating Course: I took one of these when I was a kid, sponsored by the Coast Guard Auxiliary. Time for another one, especially as the waters of Boston Harbor are much, much more dangerous than the Pennsylvania Lakes and upper reaches of Chesapeake Bay I knew growing up.

Shopping lists for boat/trailer parts and fishing equipment will have to wait until February.

So I asked him about something I’ve been puzzling over recently …is there a real difference between the gear case oil they sell for cars (which goes for as cheap as $4 a quart) and the gear case oil they sell for outboards (which can go for as high as $9 for eight ounces–$36 a quart!). By gear case oil, I mean the lubricant that goes into your outboard’s lower unit. Depending on the brand it may be marketed as gear oil (or lube), lower unit oil (or lube), and a bunch of other names. (The various names, I suspect, are partly aimed at keeping you guessing.)

The standard viscosity for both auto and marine outboard gear case oil is the same…SAE 80W-90. So is there really a difference? Or is this just another case of boat owners getting ripped off?

Dave was refreshingly candid. Not missing a beat he said “Regular old gear oil is all I’ve ever used in my engines” (he has both outboards and inboards). “It’s the same stuff.”

But I’d heard that marine gear case oil was different: that it has additives to keep it low foaming–important to keep you from blowing a seal. And it’s tackier, so that any moisture finding its way into the unit can’t get between it and a metal surface, causing separation.

Dave shrugged. “Yeah, they might add a little anti-foaming agent, but a good oil shouldn’t be foaming anyway. Foaming is usually caused by water contamination not by some failure of the oil itself. And a lower unit is sealed. Keep the water out and you won’t have an issue. Get water in and no oil’s gonna make up for that.”

So after talking to Dave there was no way I was ever spending $9 for an eight ounce tube of Mercury Gear Lube again. But I also wasn’t quite ready to go with the very cheapest WalMart has to offer. So I compromised: Lucas Heavy Duty High Performance Gear Oil (Trans and Diff Lube), $8 a quart at Auto Zone. And to make me feel a little more comfortable with the choice, the back label states “Excellent for use in outboard final drives.”

Good enough for me.

A few loose notes…

• Caveat emptor: While I would not post something I do not feel comfortable with, when it comes to deciding whether or not to follow your engine manufacturer’s specs for oil, grease, and other stuff, that’s your call. Your experience may vary from mine.
• I asked Dave what’s the difference between “oil” and “lube” and whatever else? He said there are two kinds of lubricants, oil and grease. If you can pour it, it’s oil. If you can’t, it’s grease.” I like that.
• In general, when it comes to lubricants, there is almost always a good lower priced alternative to what the manufacturer calls for. The one lube that might  not ebe asily be substituted for is OMC’s Triple Guard Grease. That stuff is tacky as heck. It really adheres.
• For Evinrude and Johnson owners, here’s a great post from iBoats.com that lists alternatives to OEM lubes.