Adjusted Trim Tab, Still Pulls Hard Right

seedlings

Petty Officer 3rd Class
Joined
Jun 5, 2009
Messages
92
1979 AMF Crestliner Muskie 550 14' (maybe 15', can't remember now) tri-hull
1978 Evi 70hp 20" gearcase

Boat always pulls right. I read up on that and adjusted the trim tab as far as it would go to the right, maybe 30 degrees, but still have to fight to keep it straight. Modifying the trim tab to be either longer or deeper may help. Another option is grind down the 'stops' cast into the trim tab allowing it to rotate further to the right. At some point there will be diminishing returns, though. 3 people aboard last night and I was driving, wife next to me and had my daughter move to different positions in the boat but that didn't make a difference.

Any other tips and tricks up your collective sleeves?

Thanks tons!
CHAD
 

DargelJohn

Petty Officer 1st Class
Joined
Feb 14, 2010
Messages
337
Re: Adjusted Trim Tab, Still Pulls Hard Right

I would not grind off the stops. Moving the tab beyond a certain degree will not help. My last couple of boats have had "No Feedback Steering" systems which ultimately solves the problem of directional prop torque.
 

seedlings

Petty Officer 3rd Class
Joined
Jun 5, 2009
Messages
92
Re: Adjusted Trim Tab, Still Pulls Hard Right

I would not grind off the stops. Moving the tab beyond a certain degree will not help. My last couple of boats have had "No Feedback Steering" systems which ultimately solves the problem of directional prop torque.

What is No Feedback Steering?

CHAD

Edit* Just watched a youtube video. Sounds very nice... what's installation involve?
 

seedlings

Petty Officer 3rd Class
Joined
Jun 5, 2009
Messages
92
Re: Adjusted Trim Tab, Still Pulls Hard Right

So, to be clear... this is an expected frustration from mechanical steering and outboards in general? I know without any power assistance that you have to fight while steering, but fighting to maintain course is 'normal' for outboard boats? This is my first boat - 2nd full season of ownership, and I'm learning all I can.

Thanks,
CHAD
 

DargelJohn

Petty Officer 1st Class
Joined
Feb 14, 2010
Messages
337
Re: Adjusted Trim Tab, Still Pulls Hard Right

It depends on the hull type, size motor, setup. In general, yes conventional cable steering systems have always been a hassle on outboards. I've had boats in the past that had the same problem, and trim tab adjustments did not help.

NFB system, you can set the steering wheel on a course, your take hands off the wheel and it will not veer off course.
 

wilde1j

Vice Admiral
Joined
Apr 15, 2002
Messages
5,964
Re: Adjusted Trim Tab, Still Pulls Hard Right

You should be able to get the steering neutral with the tab, unless you have some else going on (motor not centered on transom, etc.). I've never had a boat with mechanical steering I couldn't get balanced.

Is any of the tab missing? Tell us more.
 

seedlings

Petty Officer 3rd Class
Joined
Jun 5, 2009
Messages
92
Re: Adjusted Trim Tab, Still Pulls Hard Right

Jim, the trim tab is in perfect shape. The skeg is missing some metal, but I was told on the forums here that it shouldn't matter too much. I can take a better picture, but here it is one available with the old prop:
13lower.jpg


I did remove the motor to raise it up (before last season), but it's still in the factory bolts, so it should be centered. 6 gallon gas tank is centered in the rear of the boat, battery on the right side, usually (but not last night) extra 1 gallon of fuel opposite the battery. What pictures or information would be helpful to diagnose the trouble? I had this trouble last year, but either it is worse with the new prop (new 4 blade 15P comprop) or it only seems worse since I haven't driven for several months.

CHAD
 

seedlings

Petty Officer 3rd Class
Joined
Jun 5, 2009
Messages
92
Re: Adjusted Trim Tab, Still Pulls Hard Right

I may have stumbled onto a fix today. I've been wanting to seal up the lower transom bolts with 5200 (instead of the silicone I used last year). I noticed the motor mount was about 1/4" higher on the left side compared to the top of the transom (aluminum trim). While cleaning out and sealing the mount holes I straightened the motor relative to the transom top. Might be able to test on the water this week.

CHAD
 

emoney

Commander
Joined
Jul 19, 2010
Messages
2,551
Re: Adjusted Trim Tab, Still Pulls Hard Right

Well, it looks as if you've found the culprit before I needed to weigh in. Never assume the "set-up" as correct because lots of boats left dealerships off center or askew. Probably had all it's previous owners get told the same thing you've been told that it's "part of the boat", but I'm like the earlier poster and don't believe any properly set-up boat should pull in either direction. Key words there are "proper set-up"
 
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