Cable steering, Why?

DeepCMark58A

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I mounted a motor this past week on a boat I am restoring. I finally connected the cables to the motor and the motor turns to the right but binds steering to the left. I must have crossed a cable on the steering drum when I put the cables back in place. My question is why do they have a few wraps of cable on each drum on the steering wheel? Why not just attach the cable to the drum and cut the cables to fit with the spring tension instead go wrapping around the drum a couple of times?
 

GA_Boater

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Because that's the way it works. The drum wrap is a give and take setup, As the drum turns one side is shortened and the other side is lengthened with the springs taking up the slack.

The way you describe wouldn't steer, just stretch the springs on both sides.
 

DeepCMark58A

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It does seem like there is excessive cable on the drums but I will try working with what is there first.
 

jbcurt00

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IIRC, w the motor centered, 3 winds in each direction from the center of the drum, is enough to outfeed in both directions when turning lock to lock. Less then 3 winds and you dont have enough cable to outfeed, on most drums.
 

GA_Boater

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This pic from the referenced thread by tashasdaddy shows the wrap. The feed to the pulleys and back is from the center. There are 4 or 5 wraps and given the size of the drum, that means the cable is moved about a foot in both directions, give or take. The motor only needs about half that for full left or right

cablesteeringsetup004-1.jpg
 

fhhuber

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How many wraps is a bit variable based on the pulley at the steering wheel, connection at the outboard and the pulleys used. Sometimes you have pulleys for 2:1 and sometimes 4:1 (haven't seen 8:1 yet... but it might exist)

You should have at least half a wrap each way more than what is needed to turn the motor to its mechanical limits.
 

GA_Boater

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Fill the drum completely as in the photo and it needs no counting. Since the cable to the pulleys is from the center of the drum, as it turns the cable is unwrapped on one side and wrapped onto the drum from the other.
 

DeepCMark58A

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Like anything shortcuts are seldom the solution I will be disconnecting the cables and rerunning from scratch using the suggestions and diagrams here. The tape idea is going to help.
 

DeepCMark58A

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Well it took two tries but it connected well and was balanced, except I wound the cables clockwise and that was backwards. Found that out at the boat landing today.
 
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