MotorGuide R3 45 lb freshwater (12 V, 36" shaft, digital variable)

shop.motorguide.com/products/motors/freshwater/r3.html

The MotorGuide R3 45 lb freshwater (12 V, 36" shaft, digital variable) is a trolling motor with a 12 V system, a peak draw of 44 A and a 12 pack.

Last updated: 30 October 2026

What we found

Battery models are matched as running it across several brands, by setting each maker's published figures against the other — neither names the pairing.
12 V deep cycle marine batteries.
Sonar must not run off the trolling motor battery.
Published as 12 V · 44 A.
Specifications are published for it, each with its source.
1 figure is contradicted by another credible source. Both readings are shown below, and neither is presented as the correct one.

At a glance

System voltage 12 VPeak draw 44 A45 lb thrust — sources disagree

That is a peak, not a continuous rating. The maker publishes no continuous draw for this — see below for what they say about it — so a pack sized on the figure above is sized for the worst moment rather than for the load it will hold.

The maker’s own installation requirements: 50-amp (good) or 60-amp (best) manual reset circuit breaker, 10-gauge included, not extended beyond 1.8 m (6 ft); 8-gauge beyond that. A battery that meets the draw does not make the wiring optional.

What this device draws

Steering: Twist/Handle
System voltage: 12 V
Max amp draw: 44 A at 12 V
Max thrust: 45 lb
MotorGuide_Catalog_3-1-23_WEB.pdf · retrieved 13 September 2026
“R3-45FW 36" DIGITAL 940100180 45 LB 36" 44 12”
Source: motorguide.com/content/dam/motorguide/owners-resources/product-catalog/MotorGuide_Catalog_3-1-23_WEB.pdf
MG_SellSheet_R-Series_Revised_1-18-21_WEB.pdf · retrieved 13 September 2026
“R3-45FW 36" DIGITAL 940100180 45 36" 44 12”
Source: motorguide.com/content/dam/motorguide/owners-resources/sell-sheets/MG_SellSheet_R-Series_Revised_1-18-21_WEB.pdf
Continuous draw: A maximum; no continuous rating is published
Speed control: Digital Variable Forward/Reverse
Propeller fitted: 3bl Machete

What battery it needs

Battery type the maker recommends: 12 V deep cycle marine batteries
Circuit breaker it requires: 50 A (good) or 60 A (best), manual reset
What the maker says about capacity: reserve capacity rating will provide longer run times
How close the breaker must be: Within 180 cm (72 in.) of the batteries
Cable supplied, and how far it may run: 10-gauge as supplied; 8 mm² (8-gauge) for longer runs
Whether the engine battery may be used: Not the engine battery
What must not share this battery: Sonar must not run off the trolling motor battery

Battery and charging

Voltage, as stated: 12

Size and fit

Shaft length: 36"
How it mounts: Transom mount
Water it is built for: Freshwater

Identity

Manufacturer's product code: 940100180

Batteries documented to run this

The figures below line up. Neither manufacturer states that this pack runs this device — that is our reading of what each of them published separately, not a claim by either of them or a test by us. Even where every stated figure agrees, these can still decide it:

The device’s published draw is usually a peak, not the load it holds — the two numbers are not the same kind of quantity
A maker’s amp-hour minimum and their reserve-capacity minimum can give different answers about the same battery
Conditions attached to the chemistry, such as a speed limit for running on lithium
Whether the pack may be wired in series at all, where the device needs 24 or 36 volts
The charger, which both makers put conditions on and neither supplies
Case size, hold-down and terminal type — fitting the space is not being secured in it

Worth confirming with the device's manufacturer or a dealer before buying.

“This product is suitable for 12V trolling motors up to 70lb thrust; 2*identical batteries in series for 24V trolling motors up to 100lb thrust; 3*identical batteries in series for 36V trolling motors up to 120lb thrust.”

Only within LiTime's ceiling of 70 lb of thrust for a 12 volt motor, and this motor's 45 lb is within it — check yours before buying.

Only within Redodo's ceiling of 70 lb of thrust for a 12 volt motor, and this motor's 45 lb is within it — check yours before buying.

LiTime 12V 100Ah TMFigures comparedView battery: LiTime 12V 100Ah TM →
One of these, on its own, at 12 V.
“This product is suitable for 12V trolling motors up to 70 lb thrust; 2*identical batteries in series for 24V trolling motors up to 100 lb thrust; 3*identical batteries in series for 36V trolling motors up to 120 lb thrust.”
LiTime 12.8V 100Ah Trolling Motor Battery — Product ManualManufacturer document
LiTime
Source: cdn.shopify.com/s/files/1/0667/7220/5788/files/LiTime_12.8V_100Ah_Trolling_Motor_Battery_-_User_Manual.pdf
Retrieved September 11, 2026
LiTime 12V 50Ah TMFigures comparedView battery: LiTime 12V 50Ah TM →
One of these, on its own, at 12 V.
LiTime 12V 50Ah TM — Product ManualManufacturer document
LiTime
Source: cdn.shopify.com/s/files/1/0667/7220/5788/files/LiTime_12V_50Ah_Trolling_Motor_Smart_Battery_-_User_Manual.pdf
Retrieved September 11, 2026
Redodo 12V 100Ah Group31 BluetoothFigures comparedView battery: Redodo 12V 100Ah Group31 Bluetooth →
One of these, on its own, at 12 V.
“One 12V 100Ah Smart Bluetooth Marine for Trolling Motor battery is suitable for 12V trolling motors up to 70 lbs thrust; 2*identical batteries in series for 24V trolling motors up to 100 lbs thrust; 3*identical batteries in series for 36V trolling motors up to 120 lbs thrust.”
Redodo 12V 100Ah Group 31 Bluetooth Battery — Product ManualManufacturer document
Redodo
Source: cdn.shopify.com/s/files/1/0561/7641/0714/files/Redodo_12V_100Ah_Group31_Bluetooth_Battery.pdf?v=1756804417
Retrieved September 12, 2026
Redodo 12V 100Ah Trolling MotorFigures comparedView battery: Redodo 12V 100Ah Trolling Motor →
One of these, on its own, at 12 V.
“One 12V 100Ah LOW-TEMP battery is suitable for 12V trolling motors up to 70 lbs thrust; 2*identical batteries in series for 24V trolling motors up to 100 lbs thrust; 3*identical batteries in series for 36V trolling motors up to 120 lbs thrust.”
Redodo 12V 100Ah Low-Temp Trolling Motor Battery — Product ManualManufacturer document
Redodo
Source: cdn.shopify.com/s/files/1/0561/7641/0714/files/Redodo_12V_100Ah_low_temp_lithium_trolling_motor_battery_product_manual.pdf?v=1715855487
Retrieved September 12, 2026
LiTime 12V 100Ah TM SmartFigures comparedView battery: LiTime 12V 100Ah TM Smart →
One of these, on its own, at 12 V.
LiTime 12.8V 100Ah Trolling Motor Smart Battery — User ManualManufacturer document
LiTime
Source: cdn.shopify.com/s/files/1/0667/7220/5788/files/LiTime_12.8V_100Ah_Trolling_Motor_Smart_Battery_-_User_Manual.pdf
Retrieved September 11, 2026

Sources

Archived document
Source: motorguide.com/content/dam/motorguide/owners-resources/owners-manuals/R3 Owners Manual - 2017.pdf
Retrieved September 13, 2026
Archived document
Source: motorguide.com/content/dam/motorguide/owners-resources/product-catalog/MotorGuide_Catalog_3-1-23_WEB.pdf
Retrieved September 13, 2026
Archived document
Source: motorguide.com/content/dam/motorguide/owners-resources/sell-sheets/MG_SellSheet_R-Series_Revised_1-18-21_WEB.pdf
Retrieved September 13, 2026