Boat pulls right, what can it be?

Glastron Boater

Petty Officer 3rd Class
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Jan 22, 2017
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97
Hey guys, finally got to take my new to me boat out this weekend. It didn't have any issues at all except that I notice it pulls to the right quite a bit. I notice that it pulls most around 20-25 MPH, but the pull is there most of the time. It turns the steering wheel, not just tracks sideways.

Also, when going close to 40mph, it did not seem to pull and drive nice and straight without much steering effort.

When it pulls, you are fighting with the steering, counter steering to the left.

Am I having a steering issue?

Also, for fun, I spun in circles today and it seems to have a tighter right turn than a left... Could be just me though...


Thanks
 

wrvond

Chief Petty Officer
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Mar 2, 2010
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Look just above your prop, there should be a little fin hanging down. Use an Allen wrench to loosen it and turn it so it's pointing towards the opposite side.
 

Glastron Boater

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Jan 22, 2017
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My exhaust piece you mean?

i guess I should mention, it's a 87 force 125 outboard.

I thought about that piece being an issue, but I centered it back (as it was) when I did my water pump impeller. But I can try moving it and see how it does.

Thanks wrvond
 

jimmbo

Supreme Mariner
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May 24, 2004
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Does your engine have power trim? If so, trimmed fully in the boat will pull hard to starboard, as you trim it out, the pull will lessen and eventual disappear. Further outward trimming will cause it to pull to port. While trimmed out don't suddenly chop the throttle, it can cause a loss of control
 

gm280

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Jun 26, 2011
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I believe most boaters have similar issues with their engines as well. And it is more prevalent at certain speeds then others. And it is because of the engine trim. I had power tilt and trim, and as I accelerated, I would adjust the engine trim for best speed and steering. However, at WOT and trimmed perfectly, the steering wheel was neutral. But you better be ready when you dropped off the throttle because it would nearly jump when you backed off the speed, if you didn't down trim while backing off the speed. So you are experiencing engine trim issues for sure. Some times there is a zinc trim tab on the engine that can be adjusted to help eliminate some of those issues. However, I am not sure about your particular engine. JMHO
 

Glastron Boater

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Jan 22, 2017
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Does your engine have power trim? If so, trimmed fully in the boat will pull hard to starboard, as you trim it out, the pull will lessen and eventual disappear. Further outward trimming will cause it to pull to port. While trimmed out don't suddenly chop the throttle, it can cause a loss of control

Yes it has power trim.

Is there a way to reduce the pull?

I haven't had a pull issue on other boats I've driven, but this one is a bit smaller also.
 

wrvond

Chief Petty Officer
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Mar 2, 2010
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597
My exhaust piece you mean?

i guess I should mention, it's a 87 force 125 outboard.

I thought about that piece being an issue, but I centered it back (as it was) when I did my water pump impeller. But I can try moving it and see how it does.

Thanks wrvond


Yes, on your engine it is the exhaust piece. If the boat pulls to the right you are supposed to adjust it towards the right. Note, this adjustment is only going to help reduce torque steer at essentially one speed (rather than all speeds), so when you set it and test it, always test it at the same throttle setting/speed.

Bayliner-18-Bass-Boat-6.jpg

Here's a random picture from the interwebz - the piece we are talking about is right above the prop.
 

Glastron Boater

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Jan 22, 2017
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Yea that's my exhaust on mine.

So adjust it on the same direction than the pull?

I may play around with it... Is this doable on the water? It seems the only way to do it and test properly, instead of adjusting, driving to the lake, launching and testing. Then returning home, making adjustments, and do it all over again...
 

jimmbo

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May 24, 2004
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The steering torque is caused by several things.
1) the engine crankshaft is spinning(clockwise when viewed from above), so according to Newton's 3rd law, the crankcase, and the rest of the engine is going to try go the opposite direction(counter clockwise), which would be a turn to starboard.
2) The propeller is acting like a wheel, and with the lower blade in slightly more solid water than the upper blade(s) will try to move horizontally. On your engine, with a clockwise when viewed from the rear spinning prop, the prop will try to move to starboard. Since the prop is about a foot behind the steering pivot point of the engine, the result is the engine wants to pivot the prop starboard, inducing a torgue to starboard'. Even when the boat is going in a straight line, this does tend walk the stern sideways slightly.
3) The angle of trim when the propeller shaft is parallel to the direction of travel, the angle of attack the blades is equal on either side. If the engine is tucked in closer to the transom, the blades on the port side have, in relation to direction of travel, less pitch than the blades on the starboard side, On an engine trimmed outward from parallel the difference is reversed. On counter rotating props, the effects are mirrored

On most engines there is, as mentioned in previous posts, there is a trim tab to induce a deflection of water to counter the torque. However, its setting is only 100% effective at certain combinations of speed and trim angle.
Changing to a different line of props can affect torque feedback too, as will engine height, but most boats don't have that adjustment so...

If you have an adjustable tab, moving the rear of the tab in the direction of the pull should reduce it.

By standing behind boat in shallow water with engine tilted, you can readjust. If you are like a cat and have a dislike of water, put the boat back on the trailer, adjust and relaunch. Keep a record of your adjustments, memory will eventually let you down and you that way if you take the unit apart you have a reference
 
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Glastron Boater

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Jan 22, 2017
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Very good information Jimmbo!

I'm still fresh on boat terminology, but I think I can figure out what you mean.

I enjoy pictures if you have any, but I'm sure I can figure it out.

I will look at my outboard and re-read. I'm sure I'll understand better once I look at it with all these fins you mentioned.
 

garbageguy

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May 8, 2012
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Yes, pictures are good. Posting them here of your situation will help get you better info. I would suggest taking some, at least for yourself of pre- and post-adjustments so you can get an idea of what adjustment does what. Better yet, post'em here
 

wrvond

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Mar 2, 2010
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I have a correction to jimmbo's post: the part he's referring to is actually a torque tab or torque compensation tab. Often erroneously called a trim tab. Trim tabs are a whole other animal intended to get on plane quicker.
Otherwise, an excellent explanation.
 

Glastron Boater

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Jan 22, 2017
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I am not really looking for specific names of these parts at the moment, what's more important to me right now is- Are said parts mentioned adjustable on a Force 125 outboard?

If not adjustable, is it ok to heat and bend any fins slightly if found slightly bent?


I'm not 100 percent, but my skeg (?) ( lowest fin under prop) may be slightly curved, and it looks curved to the left.

Thanks for the info so far.
 

jimmbo

Supreme Mariner
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May 24, 2004
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Tilt the engine up as high as it will go, and take a look at the Exhaust snout. From this pic, which may or may not be exactly like yours, it looks like the forward end has a bit of adjustment range. Others pics show some similar snouts that do not have a slot. If the Skeg is twisted or curved, it might very well be causing the torqueing. Most skegs are straight. Some Hi speed Skegs, not yours, look like a wedge is added near the trailing edgeForce-Snout-F523116-4.jpg
 
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David Young

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Jul 12, 2015
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At the beginning of last summer I changed my water pump impeller. I marked my original setting of my torque trim anode or what ever its called, because I had to remove it for the impeller change. For curiosity, I installed it straight to see what it would do. The boat wanted to go to the left so bad I had to steer to the right 1/4 of a turn of the steering wheel just to go straight down the lake. I went back to the ramp and adjusted the fin back to where I had the original marks were (clockwise from the center around an half inch). The boat tracks nice and straight now with the steering wheel in the middle, as it should :) The little fin does a lot more than I would have thought.
 
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Glastron Boater

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Jan 22, 2017
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Mine is adjustable also. I also replaced the water pump impeller recently. I have never had the boat on the water before, so I do not know how it was before. I reinstalled the snout as it came off, but who knows how it felt before. I'll have the sizes I need next time I go out and do the adjustments.

The other fins are not adjustable on mine, just this snout that I know of.

Thanks.
 

Glastron Boater

Petty Officer 3rd Class
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Jan 22, 2017
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Took the boat out a few times since last update.

First time out after adjustment, I had issues with the boat not wanting to plane, it "slipped" before it could plane... Brought it to dock, took engine cover and trimmed it up, checked a few things, wiggled a couple things, reassemled, and it was fine after that. But that became my main concern at that time.


Today, I took it out again, and it's pulling hard starboard. I will adjust snout again and may be back on water tomorrow afternoon.

If the adjustment to snout doesn't change much, what else can I do?
 
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