How to Use a Minn Kota Ulterra Trolling Motor: The Checklist I Wish Someone Had Given Me

This page is about the Minn Kota Ulterra trolling motor—not the oilfield equipment company with the same name. If you're here comparing "Hercules vs Ulterra" drill bits, you've taken a wrong turn. But if you need to know how to use an Ulterra trolling motor without learning the hard way, this one's for you.

I've been running an Ulterra 112 MDI with a 36V system and i-Pilot Link for about five seasons. Maybe closer to four if I don't count the season I spent fighting with a used motor I should've never bought. In that time, I've made every rookie mistake in the book, plus a few custom ones. This checklist is the one I wish someone had handed me on day one.

Who This Checklist Is For

Maybe you just bought an Ulterra. Maybe it came with the boat you got at auction. Either way, use this before your first launch. It's not a replacement for the owner's manual—it's a way to avoid the stuff the manual assumes you already know.

Step 1: Check the Battery Bank Before You Even Turn the Key

The Ulterra 36V runs on three 12V deep-cycle batteries. You'd think that's obvious, but I've seen a boat with a brand-new Ulterra die at the mouth of the harbor because one of the three batteries was older than the motor.

According to Battery Council International (batterycouncil.org), a fully charged 12V battery should rest at 12.6–12.7V. If yours is below 12.4V, it's roughly 50% charged and needs to go on the charger before you'll get reliable performance from the Ulterra.

• Charge each battery fully, then let it rest for 6 hours.
• Use a multimeter to check voltage: 12.7V or higher is full. Under 12.4V means it's time to charge.
• If you have flooded lead-acid, check the water level. AGM batteries won't need that, but they still need a proper charger.

I'll never tie a trolling motor into the house bank again. It was one of my earlier bonehead moves. The Ulterra needs its own dedicated batteries, especially on 36V—house loads like a radio and bilge pump create voltage sag that can confuse the motor's electronics.

Step 2: Check the MDI Mount and Locking Levers

The MDI mount on the Ulterra is a great idea until it's not. A pebble, a piece of fishing line, or a corroded lever can stop the electric deploy in its tracks.

• Lift the mount's rubber cover and feel around the contact area for debris.
• Make sure the two locking levers are in the locked position. It should require a firm push.
• Spray contact cleaner on the metal contacts if you notice any dark spots. That's the #1 cause of "my Ulterra won't deploy" calls I hear from friends.

Step 3: Practice Manual Deploy On Land (Not at a Crowded Ramp)

Here's the step most people ignore. The Ulterra has a manual override for when the electric deploy fails. If you've never tried it, you won't know which lever to pull when you're drifting toward a rock wall.

I learned this the hard way in 2022. My motor wouldn't deploy, and I spent twenty minutes fumbling with the manual release while everyone at the ramp watched. The manual release is a spring-loaded pin near the top of the shaft—the owner's manual calls it the "manual stow/deploy" pin. Test it at home before you ever need it.

Do this: with the motor tilted on the mount, practice pulling the pin and swinging the shaft down. Then stow it again. It's a workout, but you'll know something that a lot of Ulterra owners never bother to learn.

Step 4: Boot the i-Pilot Link System in the Right Order

This one drove me crazy for a full season. I'd turn on the Ulterra first, then the fish finder. The i-Pilot Link connection kept dropping. If you're running a Humminbird with Link, boot the electronics first, then the trolling motor.

1. Turn on your Humminbird (or compatible chartplotter) and wait for the GPS status to show "ready."
2. Then turn on the Ulterra's i-Pilot remote.
3. Let the remote connect, usually within 10 seconds.
4. Check for software updates at the beginning of the season. Minn Kota and Humminbird release updates that fix link bugs.

If I remember correctly, the 2024 update fixed a Spot Lock drift issue on the 112 MDI. Don't quote me on the version number, but update anyway.

Step 5: Calibrate Spot Lock in Open Water

Spot Lock is the reason most people buy an Ulterra. But you'll get terrible performance if you activate it within 100 feet of the dock. The GPS needs a clear view of the sky. Metal roofs, buildings, and fishing piers mess with the receiver.

Take the boat to an open area, lower the motor, and press the Spot Lock button. Let it settle. If the boat makes a circle of 10 feet or more, you might need to jog the lock point.

There's something satisfying about watching the motor hold you within a few feet while you tie rigs. But that satisfaction comes only after you practice the basics.

Step 6: Stow and Trim Correctly After Every Trip

The Ulterra's auto-stow is convenient, but don't rely on it blindly. Last season, I hit "stow" and the motor lifted but didn't lock into the cradle. The shaft rattled sideways on the road. That was a $300 vibration sensor replacement.

After stowing, give the motor a light push. If it moves, the mount isn't locked. Also use the trim feature to keep the lower unit centered before stowing—it reduces strain on the drive.

Mistakes That Cost Me Real Money

Here's a list of things I can't get back:

• Not replacing all three batteries at once. I replaced only the dead one. The other two lasted three more months, and I paid for an extra service call.
• Skipping the inline breaker check. The 60A breaker resets, but corrosion causes voltage drop. My meters showed 36V, but under load the motor stalled. Clean the terminals.
• Ignoring the breakaway bracket. The Ulterra has a breakaway mount for hitting logs. I never tested it until a log bent the shaft. Now I test it by hand every spring.
• Leaving the remote in the boat overnight. The i-Pilot remote wakes up when you touch it. A remote bumping around in a helm drawer can drain its internal battery in a week. Put it in a cup holder or take it home.

The Total-Cost Lesson: A Cheap Ulterra Can Become an Expensive One

When I bought my first Ulterra, I went used. The price was $1,100; a new 112 MDI was over $2,500. I thought I was smart. Then the GPS board fried. $450 for the board. Then the batteries needed replacing: $510. Then a friend had to tow me in because of a wiring mistake I'd made. That taught me the total-cost-of-ownership lesson better than any spreadsheet.

Now I calculate TCO before any gear purchase. For an Ulterra, that means adding up:

• The motor itself
• Three good deep-cycle batteries (expect $150–$250 each, depending on chemistry)
• A proper onboard charger ($200–$400)
• Installation supplies: cables, breaker, connectors ($50–$100 if you DIY)
• Installation labor if you won't DIY ($200–$500)
• Two hours a year of maintenance time

The "cheap" motor ended up costing nearly the new price. I have mixed feelings about buying used marine electronics since that day—on one hand, a bargain is tempting. On the other, you're buying someone else's hidden corrosion.

My rule now: if the deal looks too good for a 36V trolling motor, the cost of not testing it is probably baked in.

Final Note

This checklist won't make you an expert. But it'll get you through the first season without the do-it-yourself misery I endured. Print it out or screenshot the list. Each item takes less than a minute.

If you're comparing the Ulterra to a Terrova or an Ultrex, good—you should. And if you're looking for the other Ulterra, the oilfield drilling company, this isn't that page. This one floats.