Possible Modification Project?

SLOWDUK

New member
I bought my ’88 V20 Dual Console just before Thanksgiving and have only had it on the water 4 times since, just running around Pensacola Bay and some of the bayous feeding it. Our family plans on using the boat for bay fishing primarily with the occasional fishing trip into the gulf. Waterskiing was a favorite of mine growing up and I would like resume that as well as teach my grand children how to ski. When I described the boat on the forum, several of you noted the large heavy engine (a 630lb 2005 Yamaha 225 four stroke) as too heavy which could reduce the transom freeboard and cause water to back flow into the cockpit through the scupper drains. My limited experience so far has indicated that yes, with a couple of adults standing just in front of the engine, water starts percolating up through the scupper drains and the engine well stars filling with water. A significant concern of mine is the lower transom height in the event of waves approaching from the stern. Never one to accept unnecessary risk and always looking for another do-it-yourself project, I’ve come up with a plan to alleviate the problem. I’m asking the forum for advice and consideration. Maybe one of you has already attempted such a fix.
First, are my concerns warranted? Does the extra weight astern constitute a significant risk?
If so, consider the following modification.
I plan to design, build and attach to the transom buoyant hull extensions left and right of the engine. These extensions would be shaped so as not to interfere with the engine’s range of motion nor touch the water with the boat on plane. Measurements indicate that there is a space 30 inches wide left and right of the motor to work with. Preliminary calculations indicate that if they extend aft 24” from the transom, 4 to 5 cubic feet of volume can be displaced below the waterline with the boat at rest (approximately 250-300lbs of buoyancy). And maybe more importantly, additional volume above the water line will add additional buoyancy in the event waves approach from astern. The design will include ladders and handrails so that the extensions double as boarding platforms.
I am considering a wooden and foam design covered in fiberglass or an all aluminum design that my son, who is a skilled welder, can assist in fabrication.
There will be those of you that recommend trading in the motor for a lighter one, but I have initially ruled out that option as the motor (a 2005 with 130 hours on the clock) has considerable life remaining and I like the additional horsepower with the quietness of a four stroke.
I’m pretty much thinking out loud at this point. I have other projects higher on my priority list and I’m not in a rush to execute this plan tomorrow. But I am asking for your experience and insight on this subject.
Thanks in advance, Slowduk
 
I think you will find that you won't get as much flotation as you expected due to the weight of the added materials at the back of the boat and also keep in mind that the surface of the water curves up from the bottom of the boat on plane... not a straight line.... IF I did such a mod I think I would keep the bottoms flat with the hull bottom but honestly I think I'd be more inclined to move batteries as far forward as possible and get plugs for the scuppers.... and of course find a lighter engine OR a bigger boat
 
Transom

Maybe you could close the transom in right in front of the motor. I have two that I have done this to and it looked good. Just make sure you have enough room to tilt the motor all the way up.
 
i'd close in the transom and put a bracket on it. your still gonna need to put plugs in the drains while your at rest.
 
I've seen some Formulas and Mako conversions that had something like you are talking about. If you look at most modern "ski boats" with a European transom, they usually have added flotation on either side of the out drive(look at Four Winns boats for inspiration). Bigshrimping on here built a Potter style bracket for his Sea Craft a few years back, its on the classic Sea Craft site, maybe he will link it on here if he notices this thread. Theres some good information on there for you about building what you are talking about. Before you start such an endeavor, i have to ask if you have tried to move as much weight as you can forward in the boat?
 
I have seen what you are describing on some aluminum "Jon" style boats with larger 4 strokes on them.

I addressed the issue on my boat with stoppers for the floor drains (just remember to pull them when it rains).

I have a 20" transom and have never had a wave come into the boat from the rear, into the splashwell yes, but not all the way into the boat.

I would think if you move some weight forward and use stoppers, the extra floatation would not be needed.

But, if you do add floatation, you only need to make up for about 220 to 250 pounds, 630# (your motor) minus say 410# (my motor) or 380# (old school 2 smoke).

Just my $.02.
 
Thanks

Thanks to everyone who took the time to comment.
Axespino’s suggestion to close off the motor well in front of the engine is a good one that the previous owner already incorporated. He mounted a piece of starboard about 8” tall with quick release clasps to separate the engine well from the cockpit. It’s not waterproof, but will inhibit a wave that enters the motor well from entering the cockpit.
Based on your advice, I went out to the boat today to take a closer look and take additional measurements.
As the most common advice was to move weight forward, I surveyed the possibilities. Currently, the batteries are installed in a compartment on the starboard side about one to two feet forward of the transom. On this dual console configuration, there are compartments port and starboard at the feet of the passenger and helm stations suitable in size for a dual battery installation. There is also a central compartment at the very bow of the boat that two batteries could fit in. Obviously, the most forward option is best for weight distribution, but does the longer cable run (approximately 25’) have negative impacts on the starter and charging systems? If the cable run has minimal negative effects, I will move the batteries to the bow. If a shorter cable run is better, I’ll move them to the amidships position at the base of the helm. Port side at the base of the passenger station would be better for left and right balance, but the helm location is easier because all of the other electrical, steering, and fuel lines run along the starboard side.
Let me know what you all think about the cable run issue.
As moving the batteries forward is the simplest and most inexpensive option, I will try that first and reassess the situation.
Thanks again for the assist and I’ll report back on the results.
Take Care, Slow
 
Thanks in a Larger Font

Thanks to everyone who took the time to comment.
Axespino’s suggestion to close off the motor well in front of the engine is a good one that the previous owner already incorporated. He mounted a piece of starboard about 8” tall with quick release clasps to separate the engine well from the cockpit. It’s not waterproof, but will inhibit a wave that enters the motor well from entering the cockpit.
Based on your advice, I went out to the boat today to take a closer look and take additional measurements.
As the most common advice was to move weight forward, I surveyed the possibilities. Currently, the batteries are installed in a compartment on the starboard side about one to two feet forward of the transom. On this dual console configuration, there are compartments port and starboard at the feet of the passenger and helm stations suitable in size for a dual battery installation. There is also a central compartment at the very bow of the boat that two batteries could fit in. Obviously, the most forward option is best for weight distribution, but does the longer cable run (approximately 25’) have negative impacts on the starter and charging systems? If the cable run has minimal negative effects, I will move the batteries to the bow. If a shorter cable run is better, I’ll move them to the amidships position at the base of the helm. Port side at the base of the passenger station would be better for left and right balance, but the helm location is easier because all of the other electrical, steering, and fuel lines run along the starboard side.
Let me know what you all think about the cable run issue.
As moving the batteries forward is the simplest and most inexpensive option, I will try that first and reassess the situation.
Thanks again for the assist and I’ll report back on the results.
Take Care, Slow
 
Slowduk I moved my batteries to a custom in deck hatch right before the cabin entrance on my cuddy. I used 1 gauge cables. I think putting them a little closer to mid-ship is better in that you don't have SO much dead weight in the bow, they won't get as much of a beating from the waves, and aren't going to get as wet with pulling in wet anchors and rode.
 
Slowduk I moved my batteries to a custom in deck hatch right before the cabin entrance on my cuddy. I used 1 gauge cables. I think putting them a little closer to mid-ship is better in that you don't have SO much dead weight in the bow, they won't get as much of a beating from the waves, and aren't going to get as wet with pulling in wet anchors and rode.

Exactly correct. There's an unused compartment in your hull, just behind the hatchway into your cuddy cabin. Cut your deck and install a hatch big enough to get your batteries through and you'll be good to go.
 
Just curious...could you cut the access hole in the cabin?

Like if you were standing in the cabin well facing toward the transom, cut into the wall at your feet?

Or is there something structural between there and the void?
 
Dual Console not Cuddy Cabin

Thanks for all who have weighed in on this project.

I know that most of the forum owns center consoles and cuddy cabins, but my boat is a dual console. The bow is an open area with a compartment in the deck for the anchor and another compartment with drains to the sea. The bow area is about the same size as the cockpit, placing the windscreen at about amidships. At the most forward part of the bow area in front of the anchor well is a hatched compartment on the forward bulkhead that I am considering for dual battery installation. Like I said in a previous post, the other options are the compartments at the base of the helm or passenger seats.

I'm going to try to attach a pictures that show interior layout and the bow compartment that I'm considering to clear up any confusion.

This link shows the most forward compartment I'm considering. The one with a tinted clear hatch that appears black in this photo. My grand daughter's knee is on the anchor compartment:

http://s944.photobucket.com/user/slowduc/media/630_zps44944fc6.jpg.html

This photo shows the helm station. At deck level immediately below the engine instruments is a hatched space suitable in size for a dual battery installation:

http://s944.photobucket.com/user/slowduc/media/631_zps34e0901b.jpg.html


Although at an angle, this photo shows the relatively equal size of the bow and cockpit areas as well as the area beneath the helm that could house the batteries:

http://s944.photobucket.com/user/slowduc/media/639_zpse316a87f.jpg.html

On another note, my preliminary research into long battery cable runs has led me to several wire size calculators. Has anyone used these? The variables required are generally the, acceptable voltage loss (3-10%), total circuit length and current in amps. I assume that the current requirement should be the output of the alternator (45 amps in my case) and not the battery cranking amps. Am I on the right track here?

Thanks Again, Slow
 
A Few More Thoughts?

First I just re-learned how to drop a pic into a post:

639_zpse316a87f.jpg


And from the pic above the two locations I am considering to move the batteries forward are below the helm behind the starboard cooler and in the bow compartment below the forward cleat.

Is it possible to cushion the battery mounts to limit the pounding they receive farther forward in the boat?

Thanks, Slow
 
Just curious...could you cut the access hole in the cabin?

Like if you were standing in the cabin well facing toward the transom, cut into the wall at your feet?

Or is there something structural between there and the void?


Randle, there is a bulkhead under the cuddy door between two stringers just aft of the cuddy step down/storage well in the forward liner.
 
rmb, there is a bulkhead just aft of well in the cabin. bout a 1/2" to 1" gap between the panels. at least on a '86 cuddy.

slow, i think the amp draw is the total load. plus when figuring distance, its from engine to batteries & back.

edit: good answer, fast fingered Bradford
 
Better Pics

I'll get better pictures this weekend as the boat is stored out of water at the Naval Air Station Pensacola.

In the mean time here are the pics I do have:

BatteryOptionscopy_zps5ba40c47.jpg


BowandHelmCompartmentscopy_zps9ff77254.jpg


BowCompartmentcopy_zpsc8e047da.jpg


This is a picture of the compartment on the passenger side amidships.

PaxStationCompartmentcopy_zps82725307.jpg


Hope that helps in the meantime, Slow
 
Sorry for asking that question about Cuddys Slowduk...I didn't mean to confuse the subject.

Thanks for the replies about my question guys...figured there was something there.

Back to your question Slowduk, I would think the batteries would be happier with option 1...seems like they would take a pounding way up front.

Good looking crew you got goin there BTW.
 
Sorry for asking that question about Cuddys Slowduk...I didn't mean to confuse the subject.

Thanks for the replies about my question guys...figured there was something there.

Back to your question Slowduk, I would think the batteries would be happier with option 1...seems like they would take a pounding way up front.

Good looking crew you got goin there BTW.

I completely agree. Option one is the preferred area.

Since you have a different deck layout than most of us (dual consoles, no step down) I'll fight my way out thru the snow to my boat tomorrow and measure back from the bow to where my deck hatch is. I'm fairly certain that even though the decks may be different, the underside where the bulkheads and stringers are is pretty much the same on all of the V's. That measurement should tell you where to make your cut for the battery placement.

Even though you could figure out exactly what gauge wire to to run from the engine to the batteries, don't over-think it. Most car battery applications use 4 gauge wire for their leads, and truthfully you could probably use that with zero problems. But just to be safe, use 1/0 AWG copper wire and you'll be fine. It's rated for 300 amps at up to 19 feet, which is roughly twice the distance than you'll be going. For your primary wires they will do the job nicely, and then, for your secondary wire feed to your panel for your electronics I'd use 4 gauge, and from there I'd use whatever came with the equipment. Yes, you can safely use a smaller gauge primary wire, but since the larger the wire the less the resistance, using 1/0 is probably overkill but you won't get into trouble using it. Oh, and if you can find it, use marine rated tinned pure copper wire. More overkill, but well worth the few extra bucks years from now.
 
Back
Top