Trim Tabs and Hydrofoil?? Help!!

adam24601

Cadet
Joined
May 10, 2004
Messages
29
I will try to keep this short since I have been getting some great information from many people on the board, but I want to lay out the whole problem and see what response I get back. Here goes.<br /><br />I have a 22 foot sunrunner boat with an I/0 motor V8 with 260hp. I recently bought the boat and have been experiencing some handling problems. First...when the boat was being sea trialed..it would list to the port side and steer itself that way without touching the wheel. We figured it was the trim tabs..when the boat came out of the water...we were able to push up on the port side tab..and I figured it was broken. I took Bennett Marine's advice and cleaned out both Solenoids and did not find any problems...took it out again and it ran better.. Still tends to list a bit and yesterday we took it out again and had a couple of times when it really went hard to port and was a bit scary!!! (the water is too cold to be dumped out!) So...I wondered if the hydrofoil is messing with the steering of the boat or what? I want to take it off..but it will require the marina to take the boat out and relaunch plus some work..which equals $$$ so I want to make sure this is the right thing to do. The tabs are moving and seem to be operating correctly. I don't know if you can still push up on the port tab..since we have not had the boat out of the water again. I love this boat....but am really getting concerned if I can't get it to ride straight. Any thoughts would be greatly appreciated.<br /><br />Thanks,<br /><br />Adam
 

LubeDude

Admiral
Joined
Oct 8, 2003
Messages
6,945
Re: Trim Tabs and Hydrofoil?? Help!!

IMHO, you are experiencing way too much stern lift with both the trim tabs and the hydrofoil both being on there. This is causing the bow to be pushed down and causing extreme bow steer. You are going to have to remove the hydrofoil.
 

JB

Honorary Moderator Emeritus
Joined
Mar 25, 2001
Messages
45,907
Re: Trim Tabs and Hydrofoil?? Help!!

I don't think running both trim tabs and a hydrofoil is a good idea, Adam. You end up with all of the disadvantages of both. I would remove the hydrofoil and learn to use the tabs effectively.<br /><br />Your listing and self steering "problem" is most likely just torque steer that can be corrected with the tab on your lower unit.<br /><br />You might also consider switching to Smart Tabs, which automatically correct list when properly adjusted.<br /><br />Good luck. :)
 

adam24601

Cadet
Joined
May 10, 2004
Messages
29
Re: Trim Tabs and Hydrofoil?? Help!!

Thanks...I hope there are more opinions out there too. The more experiences I hear about..the better informed I will be.<br /><br />Adam
 

Jdeagro

iboats.com Partner
Joined
Jul 30, 2003
Messages
1,682
Re: Trim Tabs and Hydrofoil?? Help!!

Adam;<br /><br />You do not need more opinions. If the trim tabs are completely up the hydrofoil will still lift the back of the boat at cruising speeds and above. When you have a V bottom boat lifting the boat from the motor(center of the boat) is going to create bow steering. Also, the boat lays over hard in a turn - especially to port. The reason for the port listing vs starboard is most likely the prop torque. I would also guess that the prop is a cupped Stainless Steel prop. as that could exagerate the prop torque when combined with a hydrolfoil. <br /><br />If you raise the motor as high as possible it should come out of the water enough to get at the four machine screws that hold the hydrofoil on to the cavitation plate. <br /><br />Learn to use the Tabs and the motor Trim. You may also be running with the motor trimmed all the way down when cruising, bring it up after you are on plane, so that it is running the prop perpendicular to the water surface.
 

quantumleap

Master Chief Petty Officer
Joined
Feb 16, 2004
Messages
813
Re: Trim Tabs and Hydrofoil?? Help!!

Your hydrofoil should only be held on by four bolts. Can't you raise the LU enough to access the foil? Might have to get in the water in the shallows or on a small boat to do it. I wouldn't think you need to take it out of the water.
 

crazy charlie

Vice Admiral
Joined
May 22, 2003
Messages
5,581
Re: Trim Tabs and Hydrofoil?? Help!!

Before removing the foil,are you sure the drive trimmed up enough.If the drive is trimmed too far down it will force the bow down.Do you have the correct prop on the boat.A prop for speed will also make the boat bow steer.Charlie
 

richg99

Petty Officer 2nd Class
Joined
Jan 9, 2004
Messages
181
Re: Trim Tabs and Hydrofoil?? Help!!

Adam, I thought I could leave my hydrofoil on along with my new Smart Tabs. Today, I was told by the one boat guy that I respect the most ( my regular mechanic at NorthShore Marine In Houston Tx ) that I should definitely take the hydrofoil off. <br /><br />Yours shouldn't be too difficult to get at if you can borrow a small boat or back her tight up to a dock??? can it?? RichG
 

adam24601

Cadet
Joined
May 10, 2004
Messages
29
Re: Trim Tabs and Hydrofoil?? Help!!

Thanks...I tried to get it off, but it seems like the nuts are frozen and I started to strip the screws...I really think I need to be standing and working rather than laying on my belly on a dock. I am going to see if I can find someone with a truck to pull me out.<br /><br />Thanks,<br /><br />Adam
 

adam24601

Cadet
Joined
May 10, 2004
Messages
29
Re: Trim Tabs and Hydrofoil?? Help!!

Well..the hydrofoil came off today. I have not had a chance to take the boat out and see what happens. I did notice that the trim tabs can no longer be moved by hand. I hope the foil coming off solves the listing problems..etc. I'll let you all know.<br /><br />Adam
 

adam24601

Cadet
Joined
May 10, 2004
Messages
29
Re: Trim Tabs and Hydrofoil?? Help!!

Yay!!! The hydrofoil is off and the boat steers nice and straight...gets on plane and runs very smoothly. Thanks for all your advice!!!! NO HYDROFOILS WITH TRIM TABS!!.<br /><br />Thanks,<br /><br />Adam
 

Solittle

Fleet Admiral
Joined
Apr 28, 2002
Messages
7,518
Re: Trim Tabs and Hydrofoil?? Help!!

Adam - " NO HYDROFOILS WITH TRIM TABS!!." <br /><br />Feels good when you solve a nagging problem - but I have both foils & tabs & have no problem - 23' twin V4s CC.
 
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