Re: Mercury 150XL Hard Starting
I have the same problem at times. Mine is also a 150xl. I removed the cowl to inspect when it happened. The hum noise sounds like its coming from the starter. I do see the gear come up and turn the flywheel. But it looks as if there isnt enough power to turn the engine over and thats when the hum noise comes in when the starter gear comes back down.
My batteries which is the same as yours. Are fully charged as well.
One time I had the motor idleing and my brother squeezed the fuel primer to try to give it more fuel for some reason. And the motor shut off. probably cause it got flooded. It took me over 15 min. to get it started it kept making the same hum noise. For me to finally start it I had to hold the throttle linkages at wot. Brother started motor and it fired right up i had to feather the throttle linkage so it wouldnt stall. and boy did it smoke like a *****. With all the unburned fuel in the system.
Im wondering if the problem is the starter or fuel related or something else.
Its scary when ur out in the ocean and it doesnt start. And all u hear is that dam hum.
Yes Sir,
That's the problem I have... Hopefully after adding a little WD 40 to the gear drive it prevent this. I will be going out this Saturday and see what see do. Today I could not get her to make the noise for some strange reason. You hit it right on the head with " it sound like the battery do not have enough jucie."
Try This:
Mercury outboards are one of the most popular outboards on the water. They are dependable, powerful and relatively quiet. They make high-quality, high-performance one and two-stroke engines. However, they don't always fire right up when you try to start them. There's a few things you need to know before they'll turn over.
Step 1.
Ensure there is plenty of gas in the boat fuel tanks.
Step 2.
Check your oil level and battery levels by looking at the console gauges. If either one is low, replace as needed.
Step 3.
Squeeze the primer bulbs on the hose that leads up to the outboard engines. Give them about five solid pumps. This sends fuel into the engine so it will take a spark.
Step 4.
Put the boat into neutral and insert your key into the ignition. Then push forward on the key several times.
Step 5.
Turn the key until the outboard turns over. You might notice that it chokes or is slow in starting. If it has trouble like this, move to step five.
Step 6.
Add ethanol treatment for outboard engines. This helps the engine deal with gasoline that has high ethanol content (up to 10 percent). Ethanol is an alcohol and a solvent that doesn't react well with outboard engines due to the fact that there is more moisture allowed into an outboard. It can also create sludge and deposits in outboards.
