Hydro-stablizer

[Wizard1]

I did a search of all the forums that have to do with motors but could not find anything so. <br /> I have a 57' evinrude fastwin 18hp on a 15' semi-v bottom aluminum boat with the motor's cavatation plate (anti-ventilation plate) sitting about 1/4" inch below the bottom of the boat and I have a problem getting up on plane. I have been told that a hydro-stablizer would improve my fuel milage, help stablize the boat in a turn and at slower speeds and get the boat up on plane faster. Can anyone tell me if this is true and if it would work for my setup?<br /><br />Thanks

 

[Dave Abrahamson]

Re: Hydro-stablizer

Some like them, some don't. It will pop you up on plane faster. Can't vouch for the fuel mileage increase or stabilized turns though.<br />Do a search here on the site with the word "hydrofoil". You'll find plenty of differing opinions. Then you'll have plenty of info to make your decision.<br />Good luck!<br /><br />Dave

 

[Wizard1]

Re: Hydro-stablizer

Thanks Dave, I'll do that. I did a search for hydro-stablizer so that would explain why I didn't get any hits.<br />Thanks again

 

[cobra 3.0]

Re: Hydro-stablizer

Is your motor trim angle correct?

 

[Chinewalker]

Re: Hydro-stablizer

Keep in mind - an 18hp is not a whole lot of power for a 15-foot semi-V lummie. You would probably be better served by getting yourself at least a 25hp. Getting a bigger motor would also HELP your mileage, too, as a 25 or 30 at cruising speed would likely use less fuel than an 18 lugging its guts out to maintain plane.<br /><br />Also, the AV plates on the old 18s are quite thin and won't take much abuse - which is exactly what adding the fin would be doing to the plates.<br /><br />Bottom line - I wouldn't go the stabilizer route. Assuming the set-up is otherwise maximized (correct prop for application?) then the better choice is to get a bigger motor...<br />- Scott

 

[mjbrueck]

Re: Hydro-stablizer

When you say you have a problem getting up on plane, do you mean you eventually do? If that's the case, try moving some weight forward, or getting a tiller extension (PVC pipe for the cost conscience). If you "just" can't get on plane, a hydrofoil may help give you the lift you need, but... <br /><br />I have a '57 18 Johnson, and I wouldn't add a hydrofoil to it's AV plate (just not enough aluminum there). It wouldn't surprise me if this is one of the engines you hear horror stories about the hydrofoil ripping off the AV plate.<br /><br />edit...<br /><br />On my boat, I tries several props:<br /><br />9-1/4x11 (standard prop) - gave "best" performance at all loads. 21 or 22 mph with low load (hit 4500 rpms with throttle left over) and ~ 12 or 13 with heavy load.<br /><br />9x10.5 (non-standard prop) - gave 17 mph top end at 4500 rpms, but same 12 to 13 with heavier loads.<br /><br />9x9 (standard heavy-duty prop) - gave 12 or 13 at 4500 rpms. Wouldn't fully plane before hitting WOT rpms with lots of throttle left over.<br /><br />For my boat, the stock prop (9-1/4x11) performed best whether I was fishing solo or had the boat heavily loaded.

 

[steelespike]

Re: Hydro-stablizer

With a 15ft bare utility with weight and 18hp motor properly trimmed your boat should pop up with one person and plane easily with two.I once planed a big heavy 18 hp 15 ft plywood boat with 5 light adults 120-150lbs.It wasn't easy and may have been a fluke but it stayed on plane running about 18-20 mph.