Boat does not steer well with Hydrofoil

[ksgetting]

I have a 21 foot Sea Ray (1991 200BR) with a 5.7L Mercruiser and a 17 pitch 3 bladed prop. The boat took a little longer to plane out than I would have liked and if the weight in my boat is not distributed properly, it tips on it's side too much when I turn at cruising speed. I recently installed a Stingray hydrofoil on my boat in hopes of improving both. Since having the hydrofoil installed, it planes out great, but the boat tips on it's side even worse that before, which makes it difficult to turn. If I am the only person in the boat when pulling a skier, I have to stand in the middle of the boat when turning around. Any suggestions? Would Stingray stabilizer bars help? I also saw a suggestion somewhere else to shim the foil about 1/4" above the cavitation plate.

 

[JB]

Re: Boat does not steer well with Hydrofoil

Hi, Kevin.<br /><br />The tilting of your boat is reaction to engine torque. The trim tab on the bottom of the AV plate can be adjusted to compensate for some of that.<br /><br />A more complete solution would be adjustable trim tabs that allow you to lift one side of the hull more than the other.<br /><br />Towing skiers with only the helmsman in the boat is a deadly practice. Don't do it.<br /><br />Good luck.

 

[iwldntli2u]

Re: Boat does not steer well with Hydrofoil

Get a mirror so you can sit. Standing while turning at high speed is not a good practice.

 

[ksgetting]

Re: Boat does not steer well with Hydrofoil

I have a ski mirror (a very large one) and I only pull a skiier by myself when the lake is not busy. The problem is I can't stay in my seat when turning the boat around. When I turn the steering wheel to bring the boat back around, the boat tilts on it's side instead of turning unless I shift my weight in the boat by standing in the middle. The boat is very sensitive to weight distribution.

 

[bscheper]

Re: Boat does not steer well with Hydrofoil

My dad had a similar problem in his Maxum bowrider when too much weight was forward. The cause is torque when turning in a deep vee with too much hull in the water. Try trimming the engine to get the bow out of the water prior to making your turn. This will solve your problem.

 

[ksgetting]

Re: Boat does not steer well with Hydrofoil

Thanks! The hydrofoil does cause the front (bow) of the boat to ride lower in the water. Before we had the hydrofoil, I had a similar difficulty in turning when people were sitting in the front of the boat. I wonder if the suggestion I saw elsewhere about shimming the hydrofoil might cause the bow of the boat to ride a little higher.

 

[ksgetting]

Re: Boat does not steer well with Hydrofoil

Does anyone know the website or phone number for Stingray, the manufacturer of my hydrofoil?

 

[bscheper]

Re: Boat does not steer well with Hydrofoil

My guess is that shimming the hydrofoil above the cavitation plate allows the hydrofoil to be in the water during take off and above the water once planed off. This may help keep the bow of the boat up once you are planed off. If I were you, I would remove the hydrofoil all together. They seem to work and not cause problems on smaller engines but anything 4.3L (35 mph plus) puts too much pressure on the cavitation plate and it eventually cracks. I would go with trim tabs, stainless steel prop or 4 blade stainles prop before applying a hydrofoil to the cabitation plate.

 

[akriverrat]

Re: Boat does not steer well with Hydrofoil

what you're describing is called bow steer. very bad. it can cause the boat to lean away from direction of turn with no warning. under the right conditions this can capsize the boat. the cure is to get bow up through weight distribution or trim. http://www.uscgboating.org/regulations/nasbla_ref_guide_6.pdf page 13 says that all states other than alaska require an observer while towing water skiers. but its your ticket.

 

[Ice Water]

Re: Boat does not steer well with Hydrofoil

I have a 22 foot Sea Ray SRV and installed a Whale Tail last year. First trip out it took both hands to hold it at speed. Let go of the wheel and it would turn on a dime, and almost go over.<br /><br />Get rid of the Hydrofoil, first time you have a load on in the front you will find yourself in the water.

 

[L Christopher]

Re: Boat does not steer well with Hydrofoil

I agree with those suggesting to lose the hydrofoil. Try a 4 blade prop in same size if the RPMs are correct with curent 3 blade. Mercury and Michigan Wheel both offer aluminum 4 blades around $150 - $175. Play with the trim to keep the bow up or go for the trim tabs.