Classic AquaSport
Aquasport Mechanicals - things that need a wrench, screwdriver or multimeter => Engines & engine woes => Topic started by: TheKid on February 15, 2011, 12:43:36 PM
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What's the thought behind offset trim tab anodes? I mean the fin is shifted to port about an inch.
I have one on my 140 Tohatsu and it is very difficult turning to port.
I'm wondering if I get an inline one it will alleviate this some?
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That is intentionally adjusted that way to counter the effects of steering torque. The normal adjustment technique is adjust towards the direction of the pull. If you are pulling to port, adjust the tab to port.
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The boat is difficult to steer to port. That would mean it would tend to drift to starboard with out holding onto the wheel.
The tab is offset 1" to port and positioned parallel to center line.
So you are saying the tab should be offset to starboard?
I understand adjusting/twisting the tabs. Just not sure of the offset.
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It sounds like the tab is adjusted correctly. The steering wheel pull can be drastically affected by your trim angle also.
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On a single engine boat, the tab (called a torque tab), it's trailing edge should be at about 1:00...
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I'm not making myself clear.
I know what a torque tab is. I understand the principle.
I DO NOT HAVE A NORMAL TAB.
My tab is offset, shifted, not on center-line. I'm not talking about rotation, degrees or anything like that.
When I set it up straight, 12:00, 0 degrees, it is not on the center-line of the boat. It is shifted one inch (1") to port.
I am trying to figure out the reason for this. Not how any tab works. Why is my tab shifted? Is it necessary?
(http://bpi.ebasicpower.com/mm5/graphics/00000001/TEC01201.jpg)
Let me add that this is not my tab, but it is close in that it shows what I am talking about. My tab is similar, yet it has threads on the back side to mount from the top. This one requires a through bolt, possibly the reason it is offset.
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Ohh no.
Perhaps I stumbled over my own answer. Maybe it is the mounting. I did not notice but perhaps it is through bolted.
Still, why do you suppose they would do that rather then run it straight down the middle.
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Never seen one like that... :scratch:
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Come on Bob, I didn't think I could stump you with a question.
I've since noticed that Nissan/Tohatsu and Suzuki use this type.
I've never seen it either and I have one.
It doesn't seem it would be as effective as a center-line one due to the fact that it gives the thrust/force more time/distance to dissipate before interacting with the tab.
In any event. The boat holds a steady course yet is extremely difficult to turn to port.
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The boat holds a steady course yet is extremely difficult to turn to port.
Hydraulic steering?
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Come on Bob, I didn't think I could stump you with a question.
I've since noticed that Nissan/Tohatsu and Suzuki use this type.
I've never seen it either and I have one.
It doesn't seem it would be as effective as a center-line one due to the fact that it gives the thrust/force more time/distance to dissipate before interacting with the tab.
In any event. The boat holds a steady course yet is extremely difficult to turn to port.
Not the Suzi's I know, 90 and up... :scratch:
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Im not sure why its offset either, but Mine looks just like that. I recently installed new one (from the Tohatsu dealer) and it's exactly the same.
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The boat holds a steady course yet is extremely difficult to turn to port.
Hydraulic steering?
Actually...uh...errr...not sure, being my second outboard. It feels and looks like cable. The only reason I think otherwise is the two cables or actuators going to the motor. My previous Mercury only had one cable.
You tell me! There would be a pump somewhere...correct? I plan on going through everything again this weekend.
What difference would it make in relation to the hard steering to port? Plugged line?
I am going to disconnect the motor and crank her left and right. Perhaps one of the cables, if it's cables, needs to be replaced or lubed.
One could think I would be embarrassed asking these questions. I really dont care. Between the thick skin and just wanting to get things right...if I don't know, I ask.
That's the whole point of the board right?
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The Kid,
If you don't have a steering cylinder in the tilt tube, you have dual cable steering...
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The boat holds a steady course yet is extremely difficult to turn to port.
Hydraulic steering?
One could think I would be embarrassed asking these questions. I really dont care. Between the thick skin and just wanting to get things right...if I don't know, I ask.
That's the whole point of the board right?
You are correct. Thick skin is a premium on any forum site and is to be coveted.
That stated, pics can often help with forming answers.
If it were hydraulic, as Bob stated, you would have the mentioned cylinder and lines. The supports of the steering rod must rotate freely for a smooth turning action.
Does this look like what's attached to your engine?
(http://i237.photobucket.com/albums/ff108/r-berlin/Hydcylindersteering.jpg)
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Thanks, definitely not hydraulic.
I try to post pics when I can. Usually I am work when I think of these questions or its too dark.
Thanks again.
Update. I did not disconnect and test as previously stated.
I did rotate back and fourth and the steering is fine stop to stop.
That should point to the prop torque/tab setup...correct?
Next weekend on the water I'll try making adjustments.