Stern Drives are also called Inboard / Outboard (I / O). Unlike the Twin or Single Inboard which has a propeller set at a fixed angle and must rely on a rudder for turning, these engine types steer by pivoting the propeller to the right or left. Stern Drives and Outboards can also be tilted up or down to trim the boat.

How does a stern drive steer?

Stern Drives are also called Inboard / Outboard (I / O). Unlike the Twin or Single Inboard which has a propeller set at a fixed angle and must rely on a rudder for turning, these engine types steer by pivoting the propeller to the right or left. Stern Drives and Outboards can also be tilted up or down to trim the boat.

Is a stern drive good?

Are sterndrives reliable? Yes, provided correct maintenance procedures have been carried out at the required intervals. Sterndrives on trailer boat applications are more reliable than permanently moored sterndrives.

Do sterndrives have transmissions?

A sterndrive is a marine propulsion system that is attached to a sterndrive, also known as an outdrive. The drive unit is both the transmission and propulsion. When the captain turns the steering wheel, the entire drive turns. No rudder is needed.

Can you keep a stern drive in the water?

Most bottom paints contain copper and most sterndrives are constructed of aluminum. These two dissimilar metals do not cohabitate well and underwater can turn into a battery of sorts that can lead to corrosion issues. It’s important to keep the copper in your bottom paint away from the aluminum in your sterndrive.

What is stern drive on a boat?

A sterndrive is a marine propulsion system that is attached to a sterndrive, also known as an outdrive. The drive unit is both the transmission and propulsion. When the captain turns the steering wheel, the entire drive turns.

Is Stern drive an outboard?

A sterndrive combines inboard power with outboard drive. The engine sits just forward of the transom while the drive unit (outdrive or drive leg) lies outside the hull. … Both engines have advantages, depending on the kind of boat you have and the activities you’re planning, be it fishing, cruising or watersports.

Is an inboard or outboard better?

Outboards are designed specifically for boating. Inboard/outboards are just “marinized” automobile engines stuck in a boat. Outboards provide more room in the boat because they are installed on the transom, outside the boat. … Four-stroke outboards offer much better fuel economy, less GPH, more MPG than I/O motors.

How does a MerCruiser work?

MerCruiser engines may also be equipped with a closed cooling system. This cooling system is divided in two separate sub-systems: one uses seawater and the other uses coolant (called “fresh water”). … Water from outside the boat is drawn into the system by a pump in the stern drive on inline engine models.

What is the difference between inboard and I O?

True Inboard vs I/O A true inboard is fully inside a boat and an I/O has components within and outside of the boat. A true inboard is less common. True inboard motors will be found on boats designed for skiing as they produce less wake and drive much smoother.

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How long do stern drives last?

It’s also common to expect between 10-15 years out of a well-used sterndrive and transom assembly, and then it’s a matter of continual repairs or replacing it once and for all. Sterndrives are a faster and more efficient design, as they are mounted to the rear and produce less drag.

Can you beach a stern drive boat?

If you just beach your boat stern out, it does not take much wave action or tide change to leave you stuck and in a real mess.

Are outboards faster than Inboards?

Inboards on average can run 1,500 hours before tune-ups, while the outboard counterparts typically run 750 hours before service is needed.

How bad is saltwater for a boat?

Saltwater is not good for boats because it corrodes the boat forming rust on the metal surfaces of the boat. Saltwater corrodes metal 5 times faster than freshwater. So, you need to be careful while boating in saltwater. Humid ocean air causes the metal to corrode 10 times faster than air with normal humidity.

Are stern drives good in saltwater?

Technology has also improved corrosion protection – especially in the saltwater environment – for sterndrives. … So you can have a successful sterndrive experience in saltwater.” All of those things sound good.

How do you maintain a stern drive?

1. Make a Checklist. …
2. Check Fluid Levels. …
3. Fill the Fuel Tank. …
4. Bring the Engine Up to Temperature. …
5. Change the Engine and Stern Drive Lubricant. …
6. Lubricate All Greasable Points. …
7. Replace the Fuel Filter Elements. …
8. Inspect Hoses and Belts.

What's more expensive inboard or outboard?

Cost Comparison Inboard motors generally last longer than their outboard counterparts. … So, the inboard option means less maintenance (nearly half) even though they cost more initially. Keep in mind that inboard motors also require better insurance.

Why are outboard motors so unreliable?

Many boat engines are “unreliable” because they are not taken care of correctly. While some boat engines are less reliable than others, there are common engine issues that appear from overuse, ill-maintenance, or low-quality materials.

Which MerCruiser outdrive is best?

With over 20 MerCruiser sterndrive systems to choose from, the Bravo Series and Alpha One outdrives clearly stand out as the top choices for boaters. The power of a sterndrive vs inboard engine on a boat can not be matched when it comes to MerCruiser outdrives.

How does MerCruiser heat exchanger work?

A heat exchanger transfers, or “exchanges,” heat from your boat engine’s coolant to raw water pumped from the water outside of your boat. … The tubes are cooled by the colder raw water the allowing the tubes to absorb the heat of the engine coolant.

How do you start a MerCruiser out of water?

1. Attach the outdrive muffs to a garden hose.
2. Place the muffs over the vents in the outdrive. There are two vents on each side. Make sure the muffs are completely covering the vents.
3. Turn the water source on. Allow the air pockets to work their way through the muffs.

Why are inboard boats so expensive?

An inboard motor will usually be more expensive due to it being located inside of the boat. This can make it more challenging when it comes to maintenance and repair. … A motor that has a higher horsepower, that can reach higher speeds is going to increase the cost.

Can you change an inboard boat to an outboard?

Yes, you can convert from an inboard/outboard to an outboard. Assuming someone with survey and/or hull repair experience has inspected your transom and it is sound (very important) there are aftermarket setback brackets which will bolt to your transom without modification.

Is Stern drive same as I O?

A sterndrive or inboard/outboard drive (I/O) is a form of marine propulsion which combines inboard power with outboard drive. The engine sits just forward of the transom while the drive unit (outdrive or drive leg) lies outside the hull.

What is a true inboard boat?

Inboards use direct drive or V-drive transmissions to power engines and are prevalent in larger power boats over 30 feet (or 9 meters). With only the drive shaft and propellers submerged, the entire inboard boat motor sits deep inside the hull of a boat.

Why are ski boats inboard?

From creating consistent, balanced ramps to tracking true even with a hard-edging rider in tow, today’s inboards are purpose built to perfectly pull everything from wakeboarding and waterskiing to wakesurfing and wakeskating.

How much does it cost to replace a stern drive?

A new replacement Alpha One Gen II drive retails for $5,825, while a Bravo Three retails for $9,114. These prices are for complete (upper and lower) drive assemblies, but do not include shipping or installation costs.

Which is better Stern or V-drive?

A V-drive is more efficient in delivering horsepower to the prop, losing only 8 percent, while a sterndrive loses 13 percent. Yet, all other things being equal, a sterndrive is faster and more fuel-efficient.

Is beaching a boat bad?

When you beach your boat just offshore you are much less likely to damage your boat, but there are still some possible hazards: Swamping the boat because of poor positioning or inadequate anchorage. Having the boat get stuck because of poor positioning and changing tides.

How do I get my boat off the sandbar?

If you ground your boat on a sandbar, there may be enough sand around your boat that you can stand on the sandbar and try to push your boat off. With your engine turned off, lift the bow or stern, and push your boat into deeper water.

What is a stern anchor?

Stern anchors, or kedges, are used to moor bow-to the shore. Drop the anchor three or four boatlengths out and then gently motor in using the stern line as a brake.