Launching Saturday

[Bflaherty]

From my experience if you are already struggling to get her up on plane with people in the back, the larger 21 will actually make the situation worse... I would agree with you that you definitely need to finish the interior before you change props. Although if you're nice to the folks at the prop shop in mukilteo they might let you "borrow" a 21 for a test run. I tried several props on my little havoc before I finally found one that would pull a skier without porposing (didn't have power trim so it was very sensitive to prop lift).

[TheBronze]

I'm not sure it is struggling vs having to apply more throttle. With the 140 on there, I have a LOT of range of power. I like/want to keep it in the 4k - 5k range for fuel efficiency and ease of wear on the engine. With the kids up front, it is easy to plane at 4k on initial throttle engagement. When they are in the back, that is when I have to pump it up to 5k to get that extra weight out of the water. But then it is back down to 4 - 4.5k when cruising.

I do get porpoising, even when the kids are in front though. Not a lot, but it is noticeable. I tried addressing it by trimming the engine up, but that actually made it worse. I'm wondering if one of those anti-porpoising fin things might help address this issue? I noticed it was less pronounced when I had the 17 pitch prop on there, but I was over-revving with that guy.

I have all the sundries out of the Dodger and will be loading up the 404 with them this weekend. It should add an extra 50-75 lbs between the anchor, chain, pump, lines, first aid kit, etc. That's one kid right there. Most of that will go in a storage bin, but the anchor will definitely be in the bow for the most effect.

[Kelly]

Not saying you're doing it John, but I've seen a lot of boat owners who use their power trim ineffectively. You should be able to control porpoising by trimming back down and then feathering it up as you go. If you "bump" the trim a little at a time you should be good. Trimming out too soon will almost always equal porpoising.
I've ran power trim set ups for 20 years and never had a moment where I couldn't control the porpoising with the feather technique.

[TheBronze]

Kelly,

You nailed the technique right on the head. Problem is, I'm all the way down and it still porpoises. If I trim it up any amount, it just gets worse. Like I said, though, when the kids are in front it is a different ball game.

For now, I'm going to continue to run as is, fiddle with cabin weight, etc, and see how it does. When the interior is built, it should have a few hundred pounds of wood added back in. Couple that with the gear and I think it should help to balance her out. If not, I can always get one of those anti-porpoising fin things for the outboard.

[g3bill]

I wonder if you have trim tabs? If not might want to search and get ideas... One search; http://www.lectrotab.com/how-do-trim-tabs-work/

my search; "how to stop a boat from porpoising"

[TheBronze]

No trim tabs. They are pretty spendy units. The only thing I have considered are those self adjusting ones, but I haven't seen them in action to know if they are worth the money or just a gimmick.

[Skagitguy]

Bennett has the best ! But like you are saying you will be spending a lot. On the Farallon i spent over $1000.00 with all of the extra's....was not worth it, but my other boat they worked great.

[GregJ]

John, My Skagit 17 Express porpuses when I have the engine up one notch. Skagit 17 are known for being bow light so I keep my engine down, I have a hydrofin on the lower unit and I also have a 75 pd. get me home engine in the cuddy. The extra weight isn't necessary but it does improve the ride through chop. People often ask why I don't have a bigger engine instead of my 50 hp. Evinrude. My boat will do 30m.p. and troll at 2 m.p.h. and it is light which is the main reason. I bet that once you get the cuddy done and put on a hydrofin your porpusing problems will be solved.

[GregJ]

John, I forgot to add that the problem with a hydrofin is that if you plan to beach your boat you will probably want to raise your engine and the hydrofin makes that harder to do. I can raise mine but it's a struggle. I have noticed a little more cavitation with my hydrofin also but it sure has improved handling. I use a SE Sport 300 hydrofin.

[TheBronze]

I have thought about getting a hydrofin. Not sure about difficulty raising it up since it has electric tilt.

[Bflaherty]

With electric trim / tilt the hydrofin shouldn't be any issue at all. I know with my little havoc (dead flat bottom) with the manual trim tower of power the hydrofin didn't really help much at all... With a slightly more v-shaped bottom maybe you'll have better luck but I would be hard pressed to buy another one of those fins...

I would rather spend the money for trim tabs or a fancier trim/tilt/jack mount for the outboard. But maybe that's just me...

[Skagitguy]

Like Brian said, with the electric trim / tilt there is not any problems. On my Skagit Bainbridge it had the electric trim / tilt on the Merc 115 hp and the motor did not have to work hard getting up on a plane . It was great ! Going to do the same on the Skagit i have now.

[TheBronze]

Thanks for the input guys. I appreciate it. And Chuck, I have no problem getting up on a plane either, just takes more throttle. When it is just two, it snaps right up with less. I actually haven't give it a full throttle take off yet. I bet even loaded she will pop right out and plane.