Reply To: Budget thrusters

Electric notes
Crossing the bridge, the bigger the wire the better, motor performance is dependent on the voltage supplied. Initially I didn’t have large enough wire which cut the performance by 40% upgrading the wire size across the bridge kicked it up to around 84%. I used 4AWG. The batteries will need to handle this. I chose to use the existing house bank. I have 2 X 6v Trojan T125’s (235AH total) considering the Peukert factor this will give me 30 min to 50% DOD. This is more than enough time for docking/anchoring, for occasional assistance with tacking and use as an electric dagger board.

Parts list & Cost
2 x 60A fuses
1 x 150A fuse
2 x 60” replacement trolling motor shafts
2 x Pontoon mounts
1 x ¼” sheet of starboard
1 x ½ in sheet of starboard
2 x 55lb maxim minn kota trolling motors (digital version is more efficient at lower speeds)
10’ 4AWG marine grade wire (AWG = American wire gauge) to cross the bridge.
12’ 6AWG
3’ 8AWG marine grade wire (shaft inner tube is to small for 6AWG.
Wire terminators, and extensions
1 1/2’ Longer bolts for pontoon mounts
Ordered two new props $80 each

Misc. considerations
1. The motor manual states that the motor is grounded and that the battery bank used for them should therefore be isolated as it may cause corrosion… I ignored this.
2. Cutting up the motor obviously voids any warrantee.
3. The maxim motors are not marine grade. For this reason I made them stowable, but they won’t last forever. The don’t have zincs and the internal wire is not tinned copper. That said you can pick them up on ebay for a reasonable price.