I’m back working on the boat, and today’s project was installing the new 24-volt motor for its SideShift bow thruster. The existing 12-volt unit is about eight years old and has developed a squeaky prop from a hardened seal that let in some water. The company liked my lithium battery experiments from last year, so they sent me their updated motor to test this summer.
Fair Disclosure – A 24V motor was provided free of charge for testing
I like that they removed the air vent tube, making it much simpler with just two wiring connections. Installation was straightforward with new stainless straps, 3M adhesive, fresh hardware, grease on the pins, with thread locker and anti-seize paste where needed. I replaced the battery lugs with fresh ones, added heat shrink, and sealed the connections with Sikaflex 291 sealant.
I then rewired my two WattCycle 280Ah 12V lithium batteries in series for 24 volts, keeping the runs nice and short, with a Class T 300-amp fuse and a battery shutoff switch for safety. The system is installed inside a bow storage area at the very front of the boat’s forward cabin, right near the bow thruster. The area has several ventilation holes for air flow.
The system reuses the relay from the 12V Sideshift system, and my custom hardwired toggle switch controls it on the flybridge. For occasionally recharging the battery bank, I have my TOPDON battery charger wired to it. The charger is capable of charging 6/12/24V lead acid and lithium batteries.
The upgraded SideShift thruster tested great in the dry storage yard and then in the water, pulling around 150-200 amps during operation with a 325-amp inrush current. Captain Anne gave it a spin at the docks and thinks it has little more pulling power than the old 12-volt setup.
24V SideShift Bow Thruster Powered by Lithium Batteries Video
Overall, it’s a solid upgrade for this season. I’ll report back if anything comes up. I may try a pair of the new Renogy S1 Pro solid-state batteries next year, since their high-amperage specs and extra marine safety features look perfect for this application. The WattCycle have worked well, but I fear it may be on the edge of its maximum amperage capacity.
Visit SideShift.com for more information on their thruster products
View my previous SideShift Thruster Related Videos
Products Mentioned:
- AMZCNC Hydraulic Crimper
- WattCycle Battery
- Renogy S1 Pro Battery
- Selterm Battery Lugs
- SikaFlex 291 Sealant
- TopDon Battery Charger
- Blue Sea Class T Fuse Block
- Blue Sea 300A Class T Fuse
Lithium Battery Testing Update after a few months of Boating
Quick update on the bow thruster experiment. Last season I ran the 12-volt Side Shift external thruster on a pair of 300 amp-hour lithium batteries in parallel, and it worked great. This year the company sent the new 24-volt motor, so I put those same batteries in series. It had more pull and ran fine for a couple of months, then it started cutting out at the dock. It would die, sit for exactly 60 seconds, then come back. I cleaned every connection and even checked the underwater fittings, but the pattern stayed the same.
Those batteries are rated 200 amps continuous with overcurrent protection around 210 amps, so I figure extra load from the green growth on the props finally pushed them over the limit. I swapped in a pair of AGM starter/deep-cycle batteries that can handle 900 marine cranking amps, and the thruster has been solid ever since. Next season I want lithium packs built for both deep cycle and high burst current, the kind SideShift is now offering with NOCO. I think the lithium setup will work once we get the current rating right.
