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In my opinion, boats are like bird dogs. It’s better to have a friend with one than own one yourself. But if you’re not like me and you want to buy a boat, you’re probably weighing engine options—specifically, the differences between inboard vs outboard engines.

Picking the kind of boat engine you want impacts things like the type of boating you’ll do and the costs associated with owning a boat. Some are better suited to hunting and fishing, while others are better for water sports and cruising. Some are easy to work on, while others will make you regret buying a boat in the first place. Here’s a quick guide to boat engines to help you figure it out.

Table of Contents

  • Inboard vs. Outboard: Basic Comparison
  • The Most Common Types of Boat Engines
  • Inboard
  • A Closer Look at an Inboard
  • Inboard/Outboard
  • A Closer Look at an Inboard/Outboard
  • Outboard Engine
  • A Closer Look at an Outboard
  • What’s the Best Boat Engine for You?

Inboard vs. Outboard: Basic Comparison

When comparing inboards vs outboards, you’re really comparing three types of boat engine configurations. There is the inboard, inboard/outboard, and outboard. With the first two, some or all of the engine is located inside of the boat. The engines are usually modified car engines linked to couplings to power a propeller or outdrive unit.

Outboards bolt to the transom at the stern of a boat. They are complete drivetrains that can be taken on and off a boat. Some are used independently, while others are used in conjunction with other outboard motors. With an outboard, the boater will steer the boat by moving the entire motor side-to-side.

The Most Common Types of Boat Engines

Inboard

inboard vs outboard
Inboard motors are located inside of the boat and are connected to a propeller on the outside of the boat. Watchara/Adobe Stock

Pros

  • Higher performance in water sports
  • Safe for swimmers behind the boat
  • Better wake for skiing and wakeboarding

Cons

  • Difficult to control in reverse.
  • Can’t trim for shallow water

A Closer Look at an Inboard

With an inboard, the engine, transmission, and all parts except for the propeller are inside of the boat. This is all connected to a shaft that goes outside of the boat to a propeller. There is also a separate rudder behind the propeller for turning the boat. Propellers on inboards are located farther forward (underneath the boat) than the propellers on an inboard/outboard or boat with an outboard motor.

This makes them safer for swimmers paddling around behind the boat and ideal for watersports. Boaters who like inboards also like the kinds of wakes they make for wakeboarding, wake surfing, and water skiing. Back decks on boats with inboards are completely clear for getting into and out of the water.

Because the entire drivetrain is located inside of a boat with an inboard, the propeller can’t be raised for shallow water. This limits where you can go with a boat with an inboard engine. Those not used to boats with inboards find them more difficult to drive compared to other boats, especially when it comes to backing up.

Inboard/Outboard

inboard vs outboard
Inboard/outboard owners mostly use their boats for cruising and water sports. aerial-drone/Adobe Stock

Pros

  • Car-like feel
  • Fuel efficient
  • Long life span
  • The stern is open and clear

Cons

  • Takes up space
  • Expensive to maintain
  • Not easy for DIYers
  • Heavier than an outboard

A Closer Look at an Inboard/Outboard

Inboard/outboards are found mid-size to larger cruisers. They’re not as common on dedicated fishing or hunting boats. Typically, an inboard/outboard uses a car-type engine located inside the boat that is coupled through the transom to an outdrive unit. In other words, part of the engine is in the boat, and part is outside of it.

This allows you to trim the motor or raise and lower it depending on the depth of water. You can’t trim as far up as an outboard, but you can still get into shallower water with an inboard/outboard than you can with an inboard.

Inboard/outboards can be a bit more difficult to maintain, but by using car engines, they do have some good aftermarket part availability. Because part of the engine is located inside of the boat, they take up more room. Inboard/outboards are said to have a car-like feel. They tend to be quiet, fuel efficient, and have a longer lifespan. Most inboard/outboard owners use their boats for water sports and some fishing. Users also appreciate the clear back deck for things like swimming, tubing, and waterskiing.

Outboard Engine

Outboard motors are ideal for getting into shallow water.
Outboard motors are ideal for getting into shallow water. I/Adobe Stock

Pros

  • Compact and lightweight
  • Easier to work on
  • Little to no freeze damage risk
  • Can be completely trimmed up for shallow water

Cons

  • Older outboards are loud and less fuel efficient
  • Takes up space on the swimming platform
  • Some find them unsightly

A Closer Look at an Outboard

An outboard is a complete engine, mid-housing, and lower unit bolted to the back of the boat. Take it off, and the boat has no engine or propeller. You’ll see outboards on john boats, saltwater fishing boats, flats skiffs, duck boats, center consoles, and pontoon boats. Hunters and anglers prefer outboards for a few reasons.

First, outboards can be trimmed completely out of the water, giving you the ability to get into extremely shallow areas. This also helps limit the risk of freeze damage and lets you take your boat out during colder months of the year. Outboards are also easy to maintain and lightweight. Should you have trouble with one miles into the Everglades or the wilds of Alaska, you can probably fix it. Lastly, outboards take up little to no space inside the boat, giving you a lot of room to swing a fishing rod or a shotgun.

Some knock outboards for being loud, but the latest 4-stroke outboard motors are very quiet and mild-mannered. The biggest issue with outboards is losing the backdeck for things like water sports. Lots of people go tubing behind pontoon boats with outboards, but if you’re really into swimming and waterskiing, you might want to check out an inboard or inboard/outboard. Some boaters don’t like the looks of an outboard, and older outboards can be less fuel-efficient.

Waterfowlers will appreciate how an outboard allows them to set decoys in shallow water.
Waterfowlers will appreciate how an outboard allows them to set decoys in shallow water. Chris/Adobe Stock

Inboard vs Outboard: What’s the Best Boat Engine for You?

If you hunt and fish, you should get a boat with an outboard engine. Outboards allow you to keep your boat in the water during colder months, and they’re easy to maintain in the backcountry. The ability to trim up an outboard makes it ideal for pushing a boat through shallow water. Also, you can easily upgrade outboards should you want more power or want to switch to something like a mud motor for duck season.

Those who do more water sports should consider an inboard motor. It will make the boating experience more enjoyable and leave the back of the boat and swim deck free for passengers to get on and off. You will also worry less about swimmers coming into contact with the propeller because it’s located farther forward on the boat. Inboard/outboard boaters will appreciate a lot of the pros you’d get with an inboard but with the ability to go into shallower water.