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Why Your Mercury Outboard Motor Stopped Working

by Hengbo Zhang 17 Aug 2021

If your Mercury outboard motor quit working, you might not know why or where to start troubleshooting. Fortunately, Mercury outboard motor issues are usually brought on by among a number of typical issues, and the remedies might not even call for an auto mechanic. You can look for one of the most typical issues on your own, as well as oftentimes, tools aren't required!

Exactly how Do You Troubleshoot a Mercury Outboard Motor?
Prior to you start, extinguish cigarettes or various other cigarette smoking products whether you smell fuel or not.

It's ideal to first address the most basic possible problems prior to entering into extra complicated matters. The following quick fixes may deal with the factor your Mercury outboard electric motor quit working.

Eliminate Change
If the kill switch isn't effectively connected it could very well be the resource of your electric motor troubles. Reverse the connection as well as put it right back into area. The kill switch may require to be replaced altogether-- find out more about them below.

The following point to inspect is your gear shift. It's easy to knock senseless of area, which protects against the engine from beginning. Make sure that you remain in neutral as well as try starting your engine again.

It may seem apparent, but examine anyway! Is there gas in the tank? If so, is the storage tank vent open? A closed vent prevents air from changing gas as the motor draws it out, which is necessary for shooting up the engine.

In some cases, the problems may just be that your engine propeller for mercury 40 hp has something entangled around it. This may be fishing line, extreme seaweed, or some other material that's functioned its means around the blades. Meticulously get rid of anything that might be twisted around the prop, and also provide it a checkup for any damages that may exist. If the prop is damaged, it needs to be replaced. Debris around the propeller is one of the most likely culprit if your boat electric motor starts, yet swiftly passes away.

yamaha 250 propeller

Choke, Throttle, and also Guide Light bulb
Try to begin the engine both with and without using the choke. If this does not function, try altering the throttle position. Using essentially gas can often work. Finally, squeeze the primer bulb a couple of times to make certain the engine is primed up.

Some batteries have an on/off switch. If this is true for your battery, ensure the switch is on. After that, if your engine is under 25HP, you might have the ability to utilize the emergency cord to pull-start. It's feasible to do this with up to a 50HP engine, yet realize that the higher the HP, the harder this will certainly be. If this functions, the battery is most likely the concern. You may need to replace it.

Reasons Your Mercury Outboard Still Isn't Functioning
Ok, so you've tried the quick solutions, however you still haven't determined why your Mercury outboard motor quit working. The following action is to do an extensive checkup of each system/engine part until the mystery is fixed.

Beginning System
If you listen to a clicking audio when you try to crank the engine, the starter solenoid may be to blame. Depending on the design, you may have the ability to replace just the solenoid, or you might have to replace the entire self-contained system. To check the solenoid, adhere to these steps.

If the beginning motor isn't beginning whatsoever, you likely have an electrical problem on your hands. Separate the black (adverse) cable television, adhered to by the red (positive). You'll then need to remove the battery from its housing. If the battery is damaged, change it. Nonetheless, some signs of wear may be dealt with.

Deterioration can be rubbed away with a wire-bristle brush. Any other buildup or residue can be removed with a combination of water and also cooking soda at a proportion of 1 cup:1 tbsp, respectively. If you use this combination, be sure to thoroughly dry out the battery instantly after. Finally, bill the battery as well as clean the connections. After that, reconnect the positive wire, complied with by the adverse. Use dielectric grease when reinstalling the links.

If all is well with the battery, you'll require to inspect if a fuse has blown. To examine if a fuse has blown, utilize a screwdriver to remove the electrical cover of the motor. With pliers, carefully get rid of the fuse holder. If the center is damaged, that means it's blown. You'll have to examine the Mercury outboard fixing handbook to identify the correct amperage needed to replace it. If none of this works, proceed onto the other systems till the issue is resolved.

Gas System
The fuel system is composed of the fuel pump, gas filter, check shutoffs, gas pipes, fuel pump diaphragm, and injectors. Listen for the operation noise. If you can not listen to the system trying to work, check for connection in between the fuse holder, fuse, fuel pump relay, and electrical wiring harness. Repair or change the malfunctioning component( s) if there is no continuity. If there is connection, change the electric gas pump.

If you hear the procedure audio, examine each part of the gas system individually. First, check the fuel filters and also seek obstructions, cracks, twists, or leaks in the hoses. Replace any kind of parts with damage. Next, check the diaphragm for fractures or various other signs of damage. After that, examine the vapor separator needle shutoff for bends or signs of wear. The following action is to inspect the injectors for blockages as well as resistance. After that, check for bad connections.

Lastly, note if there is any water in the fuel. Ethanol gas draws in water, which negatively impacts the combustibility of the gas. This is specifically most likely if you have not made use of gas ingredients or stabilizers. Water in the gas might also create a bad or failing gas pump. If you discover water in your gas, you may want to check that the pump remains in good condition.

You can carry out a Mercury outboard gas pump test by eliminating the ignition system cord boot from the ignition system and after that removing the ignition system with a plug outlet and also wrench. Affix a compression scale into the ignition system socket. If you have an electric motor, you may need a 2nd person to crank your engine over while you twist your throttle position open. Otherwise, you can press the throttle open with one hand and draw the rope begin.

What are the Signs and symptoms of a Poor Gas Pump on an Outboard Motor?
The earliest indicator of damages is fast fuel use. You likewise may have experienced a bumpy ride or problems with acceleration before reaching this factor. If you've experienced these issues, you can reference our guide to diagnosing (and also protecting against!) a negative fuel pump to determine your next steps.

A split, obstructed, or otherwise used fuel pump is usually the reason a Mercury outboard cranks but will not start. Seek advice from a repair handbook for your engine model and year to establish the correct substitute component.

Ignition System
The ignition system is responsible for shooting up the engine as well as keeping it running. Due to the fact that examining this system might involve triggers and also heat, maintain flammable liquids away.

The very first part of the ignition system to check is the spark plugs. Clean as well as readjust the ignition system-- they may need to be changed. Discover what to search for and also exactly how to carry out ignition system replacement with our thorough guide.

Examine the ignition stimulate with a spark void tester. If you have actually obtained a great stimulate, make certain that the air space is within specification. Readjust it if needed. If you have a good stimulate and also the space is within spec, the trouble will likely not be discovered in the ignition system.

Nonetheless, if you do not have a great trigger, salt accumulation on the ignition system caps or ignition coil leads could be triggering troubles. You'll also require to check both the ignition system caps and ignition coil leads for appropriate resistance. Replace weakened parts. When there is no salt build-up and also both components have correct resistance, inspect the ECM outcome optimal voltage.

If your spark plugs do not seem to be the issue, check that the electrical oil pump and also oil degree sensor are in good condition. If so, examine the reed valve for its condition.

If your engine is vibrating exceedingly, it might be a sign of propeller issues. You ought to have already examined the yamaha stainless steel propeller for damage and particles, but it's feasible another thing has failed. If you're still not able to start your outboard electric motor, inspect the propeller shaft for damages or splits-- these may not be right away noticeable, but could show a need for substitute. Next, use a wrench to tighten up the steering pivot and installing screw if either hangs.

yamaha 250 propeller

What is the Life span of a Mercury Outboard?
Mercury outboard engines have a strong credibility for reliability, and forever factor. Your outboard engine life expectancy, at minimum, has to do with 1,500 hrs (or, 6-8 years for the ordinary sailor). However, an appropriately kept outboard engine can last greater than 4,000 hrs! This means that your engine can last for 16-21 years before needing to be replaced.

Purchase the watercraft parts you need with PartsVu and also recommendation our Marine Tool Kits overview to learn about the tools important to your engine upkeep. If the troubleshooting overview over supplied no outcomes, speak with a mechanic. They might find the issue, or you may require to replace your outboard altogether.

This guide to fixing why your Mercury outboard motor stopped working addresses problems common to the majority of Mercury outboard models. We suggest that you situate or download the repair work handbook for your details engine to find out more, and consult a qualified auto mechanic over any kind of uncertainties.

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