2018 Mercury 250 Pro XS 2 stroke power issue

[LUguy08]

I have a 2 stroke 250 pro xs and I have an issue on starting the motor. It will run from spot to spot and then all of a sudden I lose power and the motor will struggle to turn over or not turn over at all. My graphs still operate and I've take out my battery and had it load test by 4 different places and they say the battery is good. I have checked connections and can't find any loose ones. I am trying to see if anyone has any direction or has experienced a similar issue. I would think if it were the battery my graphs would shut down.

[SilverFox579]

This forum covers your engine - Mercury - 3 Liter & 3 Liter High Performance

[EuropeanAM]

I'll move your post to the 3L forum for you. Please update your post to include your engine's serial number.

Do you have a BATTERY SWITCH? If so- move the engine cable directly to the battery (bypassing the switch) to see if the problem continues.

[lpugh]

I would also perform a compression test and put a camera in # 6

[SilverFox579]

Tell us also what specific battery, brand, size, and cranking capacity, you have.

[LUguy08]

I will work on hooking directly to the battery. I run a 31AGM, 950 CCA. Battery is an AC Delco. I keep going back to my battery. I had 2 places say bad battery and 2 say good, so I'm wondering if a cell could possibly be going or something. I'm a novice with trying to diagnose things like this on my own and search high and low for my options. I have a platinum warranty until 2025 on the motor. Motor has not thrown any warning beeps either.

[LUguy08]

I went ahead and got a new battery switch to install just in case. The original.installed switch was a blue seas 6006m which is what I'm replacing it with. Worse case scenario I can keep the old one for a emergency if that isn't the issue.

[EuropeanAM]

Be sure to report back. That switch is pretty close to the bare minimum you would get away with (when it's in pristine/new condition). So very well could be the problem if it got even a little corrosion in it.

[LUguy08]

Got everything switched out and hooked back up with my new switch. Went out on the lake for a good half day and no issues. I did notice my voltage gage on the dash seemed to read a little higher than before, so maybe it really was a faulty switch.

[EuropeanAM]

Good deal