[bht-kevin]

I have an 87 Mariner 75 HPBesides running a little rough at low RPM or idle, its hasnt had any problems. The past two times we took it out, it has what seemed like 1/2 the power it normally would for quite some time. After running it for about 15 minutes, the full force of the power kicks in and it nearly yanked my head back. After that, I didnt have a single problem with rest of the day. This has happened now on back to back trips so I guess its time to figure it out. On the second trip ( this morning )it was half speed and then it died. Anytime I would try and increase the RPMs from low to higher, it would die. I unplugged the fuel supply and re-attached and then pumped the fuel again and let it sit for a while. It started back up then and ran half speed for about 5 minutes before full KICKED back in and I was flying again. Worked great the rest of the day but still seemed rough at low speeds.Any ideas?This is my first boat, so please me gentle

[bht-kevin]

Serial is 0B1102201

[elkhunter1971]

I had the same problem, do the sea foam concentrate. your jet is probably sticking. I have had no problems since.

[studlymandingo]

have you tried cleaning the carbs yet?

[bht-kevin]

I haven't tried anything yet. I think my first step is to buy a repair manual. I know nothing about motors, but I guess I soon will Thanks for the tips! I am going to try the seafoam thing first. That is basically going to flush out my fuel system?

[bht-kevin]

Is this the one I need?Mercury/Mariner Outboard Tune-Up & Repair Manual Mercury Outboards, 2-40hp, 1-2 Cyl. 1965-1989Mercury Outboards, 40-115hp, 3-4 Cyl. 1965-1989Mercury Outboards, 90-300hp, 6 Cyl. 1965-1989