I have a 125hp 2003 elpto 2+2 Mercury outboard (it runs on two cylinders under 2500rpm and all 4 above) Last year my motor went under water. I pickeled the engine and got it running and it sounded like it was running fine. The next day I went to start it again and it was not running right, the RPMs would spike up and down and eventually it would stall out in neutral. I got 4 new spark plugs and after I looked at them i noticed the top two turned black on the tip and the bottom two still looked brand new like the bottom two cylinders were not working. Compression test is perfect in all 4.
I thought I had it fixed and went for a test drive in the water, and it actually felt like it was getting up to normal cruising speed for a few minutes, but then after a few minutes I couldn't get it to go faster than a few mphs, I would press the throttle forward and it would not accelerate.
I plan to try and repair it in a couple weeks and am looking for some advice on where to begin. Thank you.
I thought I had it fixed and went for a test drive in the water, and it actually felt like it was getting up to normal cruising speed for a few minutes, but then after a few minutes I couldn't get it to go faster than a few mphs, I would press the throttle forward and it would not accelerate.
I plan to try and repair it in a couple weeks and am looking for some advice on where to begin. Thank you.