Hi -
I seriously tried looking for this specific question but not quite sure I saw the answer I needed. On some of the 36 lb thrust trolling motors there is a choice of 30 inch or 36 inch shaft. I know they can be tilted and moved up/down but since I have never had either on a canoe I am not sure what the best option would be (i.e. is 36 going to be too much and 30 is just right or is 30 barely pushing it and 36 is just much better). I have a Wenonah Fisherman canoe and using a motor mount behind my seat. Thanks again…
30" Should be fine.
I have a 30" shaft motor for my 15’ Grumman that works just fine.
prop depth …
… I’d say at least 6" of water over top of prop .
You can run it deeper if you want , and even less , but less than 6" over top starts losing effeciency .
Measure from the top of your bracket mount block (mount it on canoe) to the water line on your canoe (at lightest load) , then take that measurement to the store and check to see if you have at least 6" over the prop (turned straight up) , when the bracket is slide all the way to top of motor shaft .
I’d say
go with 30"
I have a 36" on a little john boat and with it mounted right behind me I have to drop it all the way down in order to comfortably control it. Therefore my prop is about 24" down and I don’t like the thought of it running so deep. this really limits my ability to take it on small streams and creeks because I’ll likely bang it against numerous trees, rocks, and whaterver else is underwater.
TROLLING MOTOR SHAFT
A 30" shaft will do just fine for a canoe because your not drawing much water.
If you need to go shallow comfort is an issue because you don’t want to have to reach up too high to the controls.
30" - but length isn’t a problem
The shafts are usually adjustable. You can put the prop down as far as you want, or up as high was you want. The transom mount clamps onto the shaft casing, and you can slide that up or down. If you get a good buy on a 36" shaft, then that extra six inches isn’t any kind of a problem. On the other hand, all you need is 30".
- Big D
Another thing worth considering …
...... with almost all fixed shaft elect. troll motors , it is as simple as it gets to custom length the shaft to your preference . Nothing but simple wires in there .
As for the batt. you linked , it should be just fine at 7AH to operate your sonar for all day non stop .
I deleated my other post about your batt. question because my answer was too technical .
I also have presented your batt. and sonar questions to my nephew who is an elctronics expert , went over my understanding with him , and he has confirmed , but is going to double check that the mA ratings given for fishfinders is indeed per hr. consumption ...
edit: ... opps , the batt. response was for johnbia's post , mt minds not really focused well lately , sorry .
Trolling motor shaft
30" should work well. A trick I found is to mount your battery in the bow, with a long cable to the motor. I spliced a suitable length of Romex to the motor leads and mounted the battery clamps on the other end. This will help balance the canoe better than having everything at one end. A good deep cycle battery should last all or most of the day pulling a canoe around. I don’t know what state you are in, but watch the boat-motor regulations. In NC, ANY boat with ANY motor must be registered and those horrid numbers PERMANENTLY attached to the canoe.