Part 3 offers some insight on a few important internal upgrades, especially power management.
May 17, 2025
By Thomas Allen
Catch up on the series:
Part 1
Part 2
Most Ranger boats come standard with a unique on-board charger, which was the case with this rig. Over the years, including a Ranger Z20 I had several years ago featured the same charger. I never had an issue with it, and for the most part I’ve only heard good things about it. However, I don’t think these chargers are meant to charge lithums. We will be loading this rig up with Li-Time batteries across the board, so we needed to update the existing charger to a Minn Kota 3-bank Precision charger, which will effectively charge lithium batteries.
Advertisement
The existing charger was original with the boat, and a trusted on-board charger for many years. But this one wasn't approved to power up lithiums. Removing the old charger was simple, four screws and a drill gun. In this rig specifically, due to the limited space in the power plant, we chose to go with 36-volt batteries to power the trolling motor—two of them rigged in parallel for maximum output. It’s worth noting that if you run 36-volt batteries , you need a 36-volt charger. The Minn Kota Precision charger NAME we installed does not charge 36 volts. So, we went with Li-Time’s 36-volt charger .
The tradeoff for a modification like this on an older boat, we just need to plug two things in each night to top off power. Not a big deal, but an important detail.
I suggest an extended bit sleeve so you can reach the screw heads. Make sure all the charging cables are free and able to be removed without being tangled in other existing cables. My son Tommy worked to remove the old charger, which also offered an opportunity to clean that area out. He removed the device and wires without any trouble.
Advertisement
This charger was fully functional, and we were able to sell it on Marketplace to help us fund the charger upgrades. I say it often in these pieces, look for ways to help cut down on your expenses, it’ll keep you married and sane.
The charger was still fully functional, so we posted it to Marketplace and used the proceeds to help pay for the new charger. The new charger was ready to go in.
The new Minn Kota Precision charger is ideal for charging lithiums. Plus, we only needed two banks at this point since the dual 36-volt trolling motor batteries required a unique charger. To maximize space in this area of the boat, we elected to attach it to the underside of the compartment lid. This is exactly what I did on my Ranger a few years back. This location works very well for a charger and will keep the clutter to a minimum.
Once the lid is closed, you can see the screw heads are clean and out of the way, in fact, if you fish barefoot, you won’t even feel them. This is a perfect way to rig a new charger in an old boat.
We decided to maximize available real estate, beneath the power plant compartment lid is a great place for an on-board charger, especially when you need as much space as possible. Mock it up as centered so it'll close with no problems. Crank it down. Here it is fully installed, four bolts with nuts and washers. Here's a look at the topside, the screws are below the top plain of the carpet and won't hurt the bottom of your feet when fishing barefoot. This worked perfect. You can also see the plug-in location in the splashwell, easy and convenient.
Here's where the power cord is accessible--that's in the splashwell at the rear of the boat. Onto installing the batteries. The cool thing with lithium technology is the ability to work with various voltages and amp hours in a number of convenient footprints. These 36-volt batteries were available in a Group 31, which is the same footprint as a standard deep cycle. Dare I say that without modern lithium batteries, rigging a 36-volt system in this boat may have been impossible.
Time to place the Li-Time 36-volt, 50-amp-hour trolling motor batteries into their established location. Both batteries are in a standard 12-volt deep-cycle batterie. The boat was built to accommodate two of these to power the trolling motor. Use that same extended bit sleeve to attach trays to the floor so they don't slide around when the boat is under power. Strap each battery down to secure them to the tray. Each battery had an individual tray that was securely fastened to the bottom of the compartment, and each had a tie-down strap to secure the battery in place. We also learned that it’s easiest to place the rear battery in first so the second one can slide right in. We had to do it twice, learn from our mistakes!
I suggest facing the batteries in this manner, so you can use a short jumper per side to create the parallel system. (DO NOT RIG 36v BATTS in SERIES!) Here you can see the positive terminals linked together, and the negative terminals linked together. The main trolling motor lines went to positive and negative terminals on one battery. The dual Li-Time 36-volt batteries are rigged and ready. Remember, these are already 36 volts, so you need to rig a pair of them in parallel, not a series. There is a major difference. In fact, only one of these batteries would run the trolling motor for a decent amount of time, but based on the way my son fishes, two rigged in parallel to extend the amp hours was the best bet for us.
The original livewell lids were worn out and couldn’t take the weight of an angler any longer. We found a guy online, Facebook actually, who builds custom Ranger lid replacements out of aluminum. They are well made and durable—and matched perfectly with the previous dimensions. Look him up, “Ranger Mike” on FB, he does fantastic work.
Here are the new lids from "Ranger Mike". They're aluminum instead of fiberglass, lighter and more sturdy. The original lids were attached to the hinge with rivets, and then screws from the hinge to the boat frame. Rivets made sense here and they were very easy to securely install. Mock them up before drilling holes. I used a sharpie marker to align the edges, and the final fit was perfect. We plan to replace all the lids down the road, but being on a limited budget, we replaced the lids that needed it most first. Perhaps next year we’ll tackle the rear storage compartment lids and then move onto the front of the boat.
The process of replacing the lids is not hard, but it does require accuracy. If the lid hinge is not placed in the right spot, the lids won’t line up and you’ll have issues getting them opened and closed. The hinges attached to the boat via screws and the hinges attached to the lids via rivets.
Perfect fit. We'll be working to replace the other lids on the boat as time goes on. The lids worked out great and are capable to hold in a heavy limit of bass! The finished product looked great and fit perfectly. This was an upgrade that was well worth the time and effort.
