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Mercury Outboard Starting Problems

If your Mercury outboard is having trouble starting, there are several things you can do to fix the problem. You can look for problems in the Solenoids, Galvanic isolator, Ignition switch, Fuel flow valve, or starter. If none of these are the problem, you might want to replace them. In addition to replacing these components, you can also tighten the steering pivot and mounting bolt. These two parts may be causing the problem.


If your Mercury outboard is not cranking correctly, the first place to look is the solenoid. The solenoid is the device that enables the engine to crank when a key is turned. When the engine cranks, it should register a voltage of 12 volts on the voltmeter. If the voltage is not present, there is likely a problem with the switch, battery, or cable.

To check the solenoid, hook up a small wire to the small terminal. Connect the other end to a multimeter. If you can see continuity in the other end, you’ve found the problem. If the solenoid is stuck, try tapping it with a screwdriver or hammer. If that does not work, you can use a battery terminal tester to determine if it needs to be replaced.

Mercury outboards have a complicated starting system. The starter is operated by a solenoid. The Mercury outboard motor requires a large diameter wire and considerable amperage. The solenoid is located on the right side of the engine. The large wire goes to the starter. When the solenoid is not energized, it creates a circuit between the two large wires. This is why the outboard won’t start unless it’s starting with a new solenoid.

If the starter solenoid is getting power, the problem may lie in the ignition switch assembly. WD-40 spray can fix the ignition switch assembly, but this will not help the solenoid. In addition, the solenoid may have contact points that are welded together. If you’re electrically inclined, you can test the solenoid by testing its contacts. If the contacts are welds, replace them.

If you have a 12-volt multimeter, connect the two leads to the negative terminal of the solenoid. The positive wire should be connected to the starter motor, while the negative wire should connect to the negative terminal. If you can see the test light when the key switch is turned on, the solenoid is broken. Once the solenoid has been replaced, the engine should start normally. The troubleshooting process is not difficult if you know what to look for.

Galvanic isolator

A Mercury outboard galvanic isolator prevents damage to the metal parts of an outboard motor. Without it, the underwater metals in your outdrive will become exposed to corrosive currents. In addition, these devices are essential if you intend to use your outboard boat on shore power. Besides, they will protect you from expensive repairs if they fail to function properly.

In order to solve such problems, you need to first diagnose the cause of your troubleshooting. A failing galvanic isolator can be a symptom of a more serious problem. If the ignition system is not working properly, the galvanic isolator could cause a fire. To determine if your galvanic isolator is the cause of the problems, call a Mercury service center and get it tested.

Another cause of starting problems in mercury outboards is the galvanic cell. Installing a galvanic isolator will eliminate this problem. These devices must be installed in series with the green grounding conductor. You should be sure to have electrical continuity in the grounding conductor to avoid corrosion. This is why many marine experts recommend installing a galvanic isolator for mercury outboard starting problems.

The Mercury Product Protection Plan is another way to ensure that your engine is covered if it fails to start. Mercury Marine is offering an extended warranty for these engines. However, this warranty is only available to consumers in the US and Canada. Some excluded uses are commercial professional, not-for-profit, work-related, and local government-owned. Warranty coverage is also limited to used products imported from outside of the United States.

Ignition switch

If your mercury outboard motor is not starting properly, it may be because of the ignition switch. You can use a manual to fix your outboard and find out the causes of the problem. You can also get an online repair manual and check it for more details. You should also consult the manual if you are unsure about the issue. A mercury outboard repair manual contains more detailed information about your outboard motor.

To check the ignition switch of your Mercury outboard motor, you need to remove the spark plug. To do so, use a spark plug socket and a spark tester. If you find that the spark plug is not firing, you can replace the ignition switch. If the ignition switch is working properly, you can disconnect the tilt switch and try to start the engine. If the ignition is still not working, you can check the cylinders.

The spark plugs can also be a problem. They must be relatively clean of carbon and set to the correct gap. If you can’t start your outboard motor because of a problem with the ignition switch, it may be the emergency kill switch. If this happens, bypassing the kill switch will allow you to start the outboard motor. A properly working ignition switch is an essential part to keep your boat running.

If the ignition switch is the source of your starting problems, you can try using a 12 Volt test light. To test the switch, disconnect the ignition module cable. Then, unplug the starter solenoid terminal and disconnect the red and white wires of the ignition switch. If the white wire is connected to the test voltage, the lamplight should be turned on. If it doesn’t, you may need to replace the ignition switch or the solenoid.

Check for a faulty ignition switch by listening for a buzzing sound. If this sounds like it is coming from the ignition switch, it probably is. You can also check for a faulty ignition switch by using a multi-meter. Ensure that the connectors are easily accessible to take a voltage reading. If you find a reading of less than 9.5V, the ignition switch is faulty. To fix it, you can get a new ignition switch that matches your boat.

Fuel flow valve

There are several things you can check if you’re having trouble starting your mercury outboard. First, you need to make sure that the battery is not corroded or dirty. Next, you need to make sure that the steering cables and battery connections are free of dirt and corrosion. You should also check that the starting circuit has no voltage drop, and that the anti-siphon and enrichment solenoid valves are working properly. Check the fuel vent, too. Lastly, check the fuel lines, the fuel flow valve, and the carburetor to make sure that there’s no leakage.

The fuel pump is usually located in the same circuit box as the fuel filter. Look for the fuse labeled on the box’s lid or in the owner’s manual to find it. Once you’ve checked the fuel pump, you can check the fuel filter. If you find it’s dry, you can replace the fuse. If you’re still experiencing starting problems, you can also check the fuel filter.

Lastly, you can check the fuel pressure. If the pressure is below normal, your fuel pump may have a leak. If your fuel pressure is under normal levels, this means your compressor is not getting enough fuel. If the pressure is too high, it may be the diaphragm or a bad pump check valve. To test the fuel pressure, you can connect a fuel pressure gauge to the pulse hose.

Another cause of starting problems on your Mercury outboard is the fuel pump. The fuel pump is responsible for delivering fuel to the engine, but it also adjusts the valves, which are connected to the fuel tank. To test your pump, squeeze the fuel flow valve and make sure the hose is pointing toward the motor. If the fuel hose is clogged, it’s possible that you have a leak somewhere along the fuel line.

Besides a fuel pump, your mercury outboard should have a choke during cold starting. The chokes can be either solenoid or injection types. Either way, they must be adjusted regularly and hear a “click” sound when they’re engaged. The next step is to remove the air box and carburetors. Then, check that the solenoid gets power when the ignition switch is pressed. Check that the plunger is not missing.