Looking for thoughts on this? Have a new bow mount trolling motor to install. My boat sits nose high. Think it’s necessary to shim the motor so the shaft is closer to 90 degrees to the water?
Looking for thoughts on this? Have a new bow mount trolling motor to install. My boat sits nose high. Think it’s necessary to shim the motor so the shaft is closer to 90 degrees to the water?
no, unless you have a freak of a boat.
Mercury 250 proxs 2B115089
No, absolutely not needed.
I guess I shouldnt say "needed" maybe, but would it be useful? Seems like any angle to the motor is just wasting energy trying to pull the boat up or down some instead of only forward.
I suppose if you wanted to take that a step further, would you be best served to shim it so that it's at what I guess you could call a "steeper" than 90 degree angle? The new composite "unbreakable" shafts have a fair amount of flex to them. When I crank mine up on high I can easily see that the flex in that shaft is altering the angle of the prop relative to where it is on a lower setting.
Personally I think it's something that probably would make a difference in an experimental setting, but one that would make very little practical difference, particularly accounting for adding another potential failure point or place for play (read: noise) to develop.
2011 Skeeter ZX225
225 Yamaha HPDI Series 2
Minn Kota Ultrex 112 52"
Console: HDS 16 Carbon
Bow: HDS 12 Carbon, Solix 12 G2, Mega 360, Garmin 106 SV, LVS 34
Hadn’t really thought about shaft flex. That’s going to just add to my nose high situation especially with a 60” shaft. (Though that’s variable depending on speed). I’ve had a couple motors on this boat and none of which have ran as smooth as I thought they should for brand new motors. Wondering if this could be part of the cause. If I can come up with a good way to shim it I don’t think it can hurt anything.
Not it exactly the same but a little trim on the big motor can make a big difference.
If it sits nose high, I actually think the shaft flex would work in your favor. At least when moving forward.
Using the big motor analogy....it definitely makes a big difference when running at WOT, but very little difference when idling around. I'd contend that idling around is much more comparable to being on the trolling motor.
As you said though, if you can come up with a good way to try it out it certainly can't hurt anything.
2011 Skeeter ZX225
225 Yamaha HPDI Series 2
Minn Kota Ultrex 112 52"
Console: HDS 16 Carbon
Bow: HDS 12 Carbon, Solix 12 G2, Mega 360, Garmin 106 SV, LVS 34
What about your sonar signal? Aren't they supposed to be as level as possible for best returns? I don't know the answer, hence the ??
1998 Tr-21, 2001 Yamaha 225 OX66
If you drop shot it can be a big deal. What you will have to do is mark the scum line (fore & aft) of the boat with a sharpie. Alcohol will remove it later. When you get back home, level the 2 marks using the tongue jack. Then level the TM bracket and ducer. This will set everything level with the boat sitting un-level in the water. Try to find someone with a laser for the sharpie marks
Last edited by brushsjigs; 02-07-2018 at 06:22 AM.
You can use a torpedo level and a pocketful of change to do this...that's the technique I've always heard about for leveling a transducer. Put the level on the boat in a spot that can be easily replicated, and while the boat is in the water put coins under the back of the level until the bubble is centered up. Keep that change set aside so you can replicate while the boat is out of the water using the tongue jack. You then have the boat sitting at the angle it sits in the water and can adjust the transducer (or trolling motor in this case) so that it's level with the boat at the angle it sits while in the water.Originally Posted by brushsjigs
2011 Skeeter ZX225
225 Yamaha HPDI Series 2
Minn Kota Ultrex 112 52"
Console: HDS 16 Carbon
Bow: HDS 12 Carbon, Solix 12 G2, Mega 360, Garmin 106 SV, LVS 34
Just use a 2.99 angle finder
this confused me at first but if you think about the prop is pulling water past it or pushing backwards. The reaction of the motor should be to flex the shaft forward making things worse. (I think). I roughly calculated I need 1-1.5 inch tapered board across the 24” motor mount. Thinking I can build one out of a composite deck board. Too cold here now though.
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