New Member, Old Boat, Unsure of Year.

[jtharmo]

I agree the look of an outboard on a bracket is sexy but from an engineering standpoint I think hanging the engine on the transom is a better solution as Denny has been educating us (or in general on the effect of moving the cg toward the transom). I don't recall who posted it but one of our more knowledgeable and connected brothers shared a quote from one of the SeaCraft Oracles regarding brackets (I forget if it was Mr Potter or Mr Moesly). It went something like "if you want more room, buy a bigger boat". That definitely speaks to the original design intent. I had my Seafari on Lake Erie last year and it ready did great in the short chop. I think your conditions on NH inland lakes will be very similar.

Originally Posted by Vezo, Part II

Awesome! Thank you SSPBill!
Vezo, Part II

No problem. It's a little sloppy up here this week but generally a mild winter by Buffalo standards.

Originally Posted by cdavisdb

The twenty is relatively narrow

I agree. These are not beamy boats. With 4 gent's on board the splashwell tub and 25" transom really keeps the feet dry.

[Sparehead]

Again, thanks for the replies. I think I’ve been swayed against the bracket now. It's hard not to smile at profoundly simple statements like "if you want more room, buy a bigger boat". For me I think the bracket cons outweighed the pros considerably. I’m doing the transom anyway so I should be able to incorporate a tall splashwell that I’ll like, even if it’s a bit “busy” looking compared to a simple transom. I may even relook at the original splashwell and hinged gate, though the 20” cut is going to 25” regardless.

Originally Posted by cdavisdb

If you want to follow through on raising the cap, do some research on vertical cg. The twenty is relatively narrow and will be sensitive to vertical cg. I remember mine as already a bit tender. Adding more weight higher might be more of a problem than a benefit.

I understand the Seafari is a little more top heavy compared to the other models that use this slim hull, but would increasing the deck and cap by just 2 inches really be very noticeable? I know I’ve seen people put towers on these little boats which must be a more drastic shift in their vertical CG. Leaving aside the deck which isn’t much over water level, I’d think 2 additional inches of vertically extended hullside all the way around should only be about 10 square feet of roughly 1/4” to 1/3” thick glass. That should be on the order of 20 pounds-ish if my math is right. Admittedly, everything above that original hull joint would have a 2 inch longer moment. Would I be risking a greater severity or tendency to chine walk, or is it just that the boat will roll more while adrift?

It doesn’t sound like much but those two inches would mean keeping the stock gunnel height and in the cabin I’d be able to sit up without needing to cram my head under the windshield area.

[cdavisdb]

Thats a research question. Off hand, I don't know the answer. Its not so much the weight of the extra glass as the additional leverage of everything else thats 2 inches higher .There have been several ways to estimate changes in cg,posted in these forums. Sorry, I don't have the location. Somebody else will. 2 inches might be insignificant or important. Play with the numbers.

I don't think chinewalking is an issue if you put the right engine on it. Mine had a 150 black max, more that enough power for offshore with a huge load and never any tendency to chinewalk, although flat out when it was light was beginning to feel a little bit unstable.

Having easy sitdown headroom in the cabin is huge , one of the things I love about my 25. Worth some change in cg, as long as its not large.

[Bushwacker]

A Seafari is about 200 lbs heavier than a CC model, and most of the extra mass is in the cap, windshield, cabin door and bulkheads, but the basic hull weighs about 1600 lbs! My gut feel is that raising ~150 lbs a couple inches is basically a nit compared to the mass of the basic hull and bulkheads which aren't moving. I suspect that the effect on vertical CG is smaller than what you get when you mount a T-top with a fiberglass cover and an electronics box up about 7 feet off the deck of a CC model!

Also keep in mind that hull shape has a big effect on initial stability . . . the 20 has a relatively low (~18 degree) deadrise hull, so it's fairly stable at rest. I remember rafting up with Connor a few years ago on an overnight adventure up to Mosquito Lagoon, and I was surprised that his 25 was noticeably more tipsy than my 20 when I climbed aboard for dinner, despite it's 6" wider beam and heavy I/O engine and big fuel tanks deep in the bilge! It's vertical CG is probably lower than it is on my outboard model, but the difference is the extreme 24.5 degree deadrise on that hull, which is even higher than on Moesly's narrow 6.5' beam 25-30' race boats!

[Vezo, Part II]

Ol' Pappy always comes thru with an interesting perspective! Gotta give it to him!!!

Part II

[Sparehead]

Thanks for the feedback. I’ll continue to give it thought. All I’m sure of at this point is the joint area will need work no matter what I decide. Simply drilling new holes into that already overly drilled glass would be just asking for trouble, plus it would bug the crap out of me to leave it like that.

It’ll probably be another month before I even get back to the boat, but let me ask one more question you’re all likely to have experienced opinions on. Assuming I hang a relatively heavy modern 150 on the transom and relocate the battery/s forward and under the deck, and assuming I build a fiberglass splashwell around the transom cut that comes close to the rear gunnel height, other than saving a little weight is there any advantage to going with a 20” outboard over a 25”? I understand the 25” has the advantage of having the powerhead further above the water and will be less like to suffer water intrusion from launching from a steep ramp. As I’ve dropped the bracket from my plan I’m not sure how big these advantages are now or if there’s anything else I’m overlooking.

[Bushwacker]

Originally Posted by SSPBill

I agree the look of an outboard on a bracket is sexy but from an engineering standpoint I think hanging the engine on the transom is a better solution as Denny has been educating us (or in general on the effect of moving the cg toward the transom). I don't recall who posted it but one of our more knowledgeable and connected brothers shared a quote from one of the SeaCraft Oracles regarding brackets (I forget if it was Mr Potter or Mr Moesly). . .

That might have been me . . . Carla brought her folks by one day to show them my boat while I was installing the new galley seat! When I asked Carl what he thought of the bracket, his reply was "Why didn't you just make the boat longer?!" Easy for a boat builder to say (and do!)

He also noticed my clipboard with the "To Do" list, and said "I see you have the traditional boat owners job list, the one where you cross off one item as you complete it, and then add two more!" Really nice guy with a great sense of humor!

[Bushwacker]

Originally Posted by Sparehead

. . . but let me ask one more question you’re all likely to have experienced opinions on. Assuming I hang a relatively heavy modern 150 on the transom and relocate the battery/s forward and under the deck, and assuming I build a fiberglass splashwell around the transom cut that comes close to the rear gunnel height, other than saving a little weight is there any advantage to going with a 20” outboard over a 25”? I understand the 25” has the advantage of having the powerhead further above the water and will be less like to suffer water intrusion from launching from a steep ramp. As I’ve dropped the bracket from my plan I’m not sure how big these advantages are now or if there’s anything else I’m overlooking.

As for the weight difference between short and long shaft motors, I've seen anywhere from 8 to 15 lbs difference quoted on the E-TEC's, which I think would be easily offset by moving batteries forward. However some motors, such as the 115 E-TEC, use a significantly different gear reduction on the longer shaft version, like 2.25:1 instead of 2.0:1, so that would be something to check out on whatever motor you select. (Be sure you use wet weights when comparing motors, because 6 qts. of crankcase + gear oil adds another 11 lbs or so to the weight of a 4S motor!)

I know Capt. Terry stayed with a 20" motor when he repowered his Seafari and seemed a little concerned about the loss of freeboard at the transom, but he didn't move any batteries.

Regarding dunking the powerhead when launching from a steep ramp, I assume you're talking about a roller trailer like mine with minimal friction in the roller system. If you have a roller trailer, I'd strongly recommend using a PowerWinch on it, and you can use the winch clutch to control how fast it comes off the trailer. I normally just back the trailer in enough to get the tires wet, so water is shallow enough close to the trailer that I'm more concerned about boat hitting the ramp if it comes off too fast, but I've always been able to control it with the winch. I previously had a 2-speed Fulton manual winch that could free-spool, but it also had a brake on it that was very useful!

[jtharmo]

Originally Posted by Bushwacker

That might have been me . . . Carla brought her folks by one day to show them my boat while...

You know, Lee Iacocca never stopped by my Dad's house last year when we were buttoning up his 64 1/2 Mustang. I am so jealous of you FLA guys.

I hate quoting someone else when I am not 100% positive but this is one that stuck with me.