Why Won’t My Outboard Boat Engine Turn Over!?


It happens to most of us! You jump on a boat, turn the battery switch on and hit the key switch. Then, nothing happens. Here’s what to do if your engine won’t kickstart!

Why won’t my outboard engine turn over? There are multiple reasons why your engine won’t turn over. There are five major things that you can troubleshoot to get your engine turning over. The battery, battery cables, starter solenoid/relay, the starter itself and the key switch.

This article covers exactly how to diagnose a boat engine that won’t turn over and how to troubleshoot the source of the problem step-by-step.

What Do You Do If Your Boat Won’t Start or Click?Boat wont turn over

Technically speaking, there are a ton of components that lead to the starting system. This includes the key switch, to the computer, to all the wiring and cables connecting all of these components, and so on.

However, when an engine won’t turn over. Usually 75% of the time the issue can be traced back to five culprits.

These five faulty components include the battery, battery cables, starter solenoid/relay, the starter itself and the key switch. (Which also fails from time to time).

So, what do you do if your boat won’t start? First, you need to begin the troubleshooting process. This is done by using a load tester to check the battery and battery cable status’.

You can do this by locating both the positive and negative battery cables on the boat engine. Next, hook up the ground clamp to any ground that is visible on the engine.

Then you’ll want to hook up the positive clamp to the positive cable on the starter!

After you’ve hooked everything up, you can apply the load and see what the tester reads.

You’ll want to hook up the starter as this will simultaneously test all of the cables. As well as the battery, coming from the starter. Which provides it with the energy needed to turn the engine over.

If you don’t receive a proper reading here. You should check the cables directly on the engine as this will eliminate the engine and only test the cables and the battery.

If this test also fails, then you should go directly to the battery and load test it. This will tell you if you need to replace or charge your battery. Or if there is something faulty happening with the battery cables!

Here is some more information on How To Take Care Of Your Boat’s Batteries To Make Them Last Longer!

How Do You Know If Your Boat Starter Is Bad?

In order to properly diagnose a faulty boat starter. We have to take a look at the batteries. It’s important to remember that all batteries have a shelf life. This means that some go bad and most need to be maintained.

Sometimes you might get lucky and find a loose or dirty connection to be the issue. When this isn’t the case, you can look for anything that is in line with the cables. That connects the battery or batteries to the engine.

Outboard has spark but wont startTypically, you will only find a battery switch for the positive cable. The boat might also have power posts that connect the batteries from somewhere in the front or middle of the boat.

To the engine via the posts on the transom.

First, make sure the battery switch and the related power posts are clean and not loose. There should also be no visible signs of corrosion. Verify the battery switch has not failed by not turning on.

And allowing the power to flow through it- even when you turn it to the ON position.

After you perform these tests. You will have verified there is nothing wrong with the battery, connections, battery switch or power posts.

If at this point you are still getting a bad reading on your load tester. Then we know that the battery cables are the issue.

Otherwise, whatever component you found to be faulty can easily be swapped out and replaced.

How Can You Tell If It’s The Starter Or The Battery?

Once we’ve ruled out the battery as the culprit, it’s time for us to check our starting system.

We are going to be making sure that the starter is getting the right amount of voltage. In order to enable it to turn on and begin turning over the engine.

This is an easy check that will confirm the status of the starter relay and if it is operating properly.

There are several different types of relays or solenoids that come before the starter. Which will also have a solenoid built into it. These components operate by controlling the electricity going to the starter.

The battery cables bring in the high power voltage needed to turn over the engine. The relay or solenoid works to control that high power, using a lot less power.

Whenever power is supplied to one side of the relay. It allows the high power to flow freely on the other side of it. When we shut it off completely, it stops that flow. Effectively shutting off the opposite side.

So, at this point, you will need to take your voltage meter and connect the negative. (Or ground meter lead) to the ground. Then, connect the positive lead to either the yellow/red wire or the brown wire that leads to the solenoid located on the starter.

Turn your meter to voltage DC and hit the key switch to see what reading we receive.Boat won't start no power

We are looking for 12 volts or battery voltage. If you see that, you can move on. On the other hand, if you don’t see it, you will need to backtrack and figure out why you don’t have it.

By “backtracking”, we mean following the wire from the starter. And then checking for that voltage on the other side of it. Which is usually at another solenoid or relay.

Here, you can hit the key switch again and see if there is voltage coming out of the relay or solenoid.

It is important to also verify if there are 12 volts sitting on the other side of the relay. In order to flow through the relay to the starter when you hit the key switch.

Different engines and manufacturers are going to have different setups and wire coloring schemes. Also, depending on the age of the equipment and whether it is a two or four-stroke engine, the system will vary.

Despite the differences in equipment, it is crucial to remember. That the process and flow of the system remain the same.

You will need to follow that wire back through the system. Until you arrive at the key switch which is what initiates the entire process.

There are many different types of chargers ranging from onboard boat chargers to plain battery chargers. The main thing to remember with any setup is the amperage that we are putting into the battery.

Generally, two strokes will be easier than four-stroke engines to troubleshoot. This is due to the introduction of computers and more wiring!

A simple yet effective trick to be able to complete the troubleshooting process is to follow the wire and wire color. Nine times out of ten you will find that it is the relay or solenoid that is the issue.

If that is not the case, it is usually the key switch. At this point, you shouldn’t need to go much deeper than that.

How Do You Test An Outboard Starter?

Once we’ve gone through the troubleshooting process and have arrived at the starter. This is where things get a bit easier as we have a tip that will allow you to test your system and bypass all of the other steps!

If you’ve dealt with outboards for a long time, you can probably remember a time where you had to smack the starter with a hammer or something hard in order to get it spinning.

Sometimes, we still have to do this! It also works on trim units and most of the time you can get them to work in a pinch. In the event that they get jammed up.

When it comes to your starters. You need to verify that the Bendix is recessed into the starter and isn’t stuck in the flywheel. This is easy, all you need to do is push it back down into the starter.

Then, you can simply take your remote starter button and connect the yellow/red or brown wire on the starter to the power cable of the battery.

At this point, hit the button and see if the starter spins up and turns the engine over.2 stroke outboard motor won't start

You can also take a screwdriver that has a plastic or rubber handle. (That won’t allow electricity to flow into your hand!) And jump the solenoid the same way.

If nothing happens, you will most likely need a new starter. You can troubleshoot further by taking this starter off and disassembling it to see if you can clean the brushes and fix the solenoid if that is the issue.

You can also turn the key switch to the ON position. If you want to start the engine and then jump the starter again. As long as the engine is getting spark, has compression and is getting fuel, it should fire right up!

Check Us Out!

Now that you know how to diagnose a non-starting engine, check out these other helpful articles packed full of information to help you with your boat!

The Different Sections Of An Outboard & How They Work

The Advantages & Benefits Of Center Console Boats!

What Is Tilt Trim On A Boat? What’s The Difference?

We’d also like to invite you to Check out our YouTube channel where we show you step-by-step videos on all things boating!

Aaron Hilligoss

Aaron has been working in the Marine Industry for over a decade and holds certifications for Yamaha and Mercury Marine. It is not uncommon for him to own and be working on at least three different boats at any given point in time!

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