I am getting massive torque steer on my boat when WOT and I have trimmed the motor up till it starts to porpuse, and then back it in so it stops flat.
Issue is that at WOT, I get about 32MPH, at about 4800rpm, but I get starboard torque steer with the trim tab centered. I clicked it once to the right, and now I get massive torque steer to the port at WOT.
Is it normal to get massive torque steer at top speed.? If I slow down to about 28 by triming in the torque goes away.
Last edited by VAKNCO; 04-03-2019 at 04:39 PM. Reason: changed 480 to 4800 on RPM
From neutral on the trim tap ( straight back) it will go the the right. Usually going the the right with the tap 2 clicks fixes it. Never heard of it going either way when still moving the tap the same way. This is with 3 blade props Four blade props, tap is usually great straight back. My guess would be your trimming to far out.
Motor height is way off one way or the other. To high or to low. To bring the prop out of the water so much that the slight Direction change in the steering wheel can cause the torque in either direction.
Have an adventure everyday !
2006 PT 175 TX 60 HP.
I believe the motor height is the same as what the factory set, but I am not the original owner and will check the height on it.Originally Posted by gatorglenn
Regarding the trim tab:
The boat was pulling starboard when set straight, so I turned the trim tab toward starboard, 1 click - that's correct, right?
After the change, the boat now pulls to the port side.
WOT range on that motor is 4750-5250. Set motor at hole #2, IF you have a SS Prop. If not, get one. I've always set my Tab (multiple boats/engines) as far as it would go to Starboard.
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When I got my boat the torque tab was turned as far left(port) as possible. I straightened it and have noticed that my boat does pull a little toward the port side now but it steers much better. Motor height needs to be checked. My P2P is at 6.75” and with no jackplate, I’m not loving the idea of moving the motor but it has to be done.
My boat porpoises at full trim and I’ve put a camera back there and at wot my cav plate is underwater.
If if I were you I would see where your cavitation plate is when you’re wot and as fully trimmed as possible.
2006 Triton SP-185, 2006 Evinrude Etec 90, PowerTech NRS3, Garmin Echomap Plus 73CV & 93SV
The motor is at hole #2. I do not have a SS prop, aluminium, along with a backup... I am likely not buying a SS one at this point unless I go through these 2. :-)
If I turn the trim tab more towards starboard, won't that make it want to turn to port even more?
Can you define what "fully trimmed" is?
My method is to trim out until it starts to porpuse, and then trim it back in so it stops porpusing.
Thanks.
I was having a similar problem and Gatorglenn helped me out by explaining about how to find neutral trim to help with torque steer. I can not explain like he did but you may be able to find the thread. One thing I learned is I was over trimming the boat and the addition of a 4 blade prop also helped with the handling. I think Glenn hangs out more in the Tracker forum now but he does stop in on the tin boat forums and help out also.
There's a tracker forum?
It is right below the tin boat forum
Trimming the motor out or up to far. Will cause a lot of the problems with torque steering. Getting out of the hole, with the motor tucked under. Once on plane. Start trimming a little at a time. Until the torque is gone. Stop there. The steering wheel should be equal turning left and right. This is ( neutral steering). That is the boats preference on trim angle. At that point is where you want to work a motor height. If the cav-plate is still buried. You want to raise the motor in 1/4” increments. With out a jackplate, you can only move 7/8” at a time. By moving motor a hole at a time. The third hole is usually best for a 115 on this size transom. With a 75hp you really need only half that move, like half inch.
This isnt to say you can’t leave the motor where it is. If so trim to neutral steering, and work on the proper size pitch of prop. To get the motor in it max rpm range at neutral steering. Then you’ve got what you’ve got.
Have an adventure everyday !
2006 PT 175 TX 60 HP.
What is the pitch on your prop 17 ?
It's a 12 3/4 and 21 pitch
Here's a Pic of the motor from behind. I took it out today, and didn't trim it out as much, just to where it started to torque steer. Max speed I got was 28, RPM at 4800IMG_20190406_113749.jpg
I am not expert but I think your prop might be to big. I have a 75hp 4 stroke and it has a 17p.
Is your motor a BigFoot.
Have an adventure everyday !
2006 PT 175 TX 60 HP.
I don't think it is... it's the original that came with the boat, 2003, 75HP ELPTO, 3 carb motor. It came on the bass boat, so don't think it's a bigfoot
I believe this prop is what came with the motor from the factory, on the PT185. When I replaced it last year, it looked original (but what do I know).
Way too much prop! 17p is what you need. I have a rt178 with a 75 merc 4. I run a 17p 4 blade. My steering torq has been horrible, installed hydro steering to help battle it.
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I tooke the boat out Saturday, and trimmed it out on WOT at 4800 - 5000 RPM (WOT on this is 4800 - 5250), until it just started porpusing... and I then trimmed in to stop porpusing and checked the torque, and it pulled to the port side pretty well, so I trimmed in more until I didn't get the torque steer to the port side. In keeping the RPM in the 4800-5000 range, I lost about 4MPH and I am getting about 28 now, with 1/2 tank gas, and 2 people on board, empty livewell.
I thought I would get mid 30's out of a 75HP with a 21 pitch prop, but maybe that was hopeful thinking.
Oh, my first run didn't go so well, as I had trouble getting on plane. It was because some fool forgot to put the plug in on the boat before launching and was therefore carrying several hundred more pounds of weight on the back of the boat..... made it back to dock safely and plugged it up.
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