I have a 2007 mercury 2 stroke that does not like to run very smooth at trolling speed.I have changed the plugs a few times and it didn't change anything.I heard that it may be timing or need to adjust the carburetors.Just wanted to know if anyone has any info?

She probably won't troll very well being that big. I know 50hp doesn't seem that big in today's boating world, but for trolling...it is.

She's loading up on the plugs at idle for long periods of time. You can make a few passes then open it up across the lake for a lap or two if you need to troll with that motor.

If it were me... I'd get an electric for the bow or stern and use that. It will save wear and tear on your motor, and be a lot quiter.

Thanks tzone for the reply. I guess I will have to go that way for now or try something else.

tzone nailed it- the newer motors just aren't engineered to be good trollers, especially since those mfg's offer up such a great line of motors of lower hp to handle that job.
If you have the transom space, try and find a nice low-buck trolling motor from 6-15hp (depending on your boat size) and put a 6 or 7 inch pitch prop on it. Having a kicker is a kick, and saves some of that wear and tear on you main engine.

I've been able to do some jet tuning and use a hotter plug on an older (1976) Johnson 40 I have up north and it trolls quite well without loading up. I've done the same thing with my 1978 Johnson 55hp I have on my Lake Erie walleye boat, but I don't troll with that too often since it carries a 15 kicker as well. I actually had a newer Johnson on the walleye boat (a 1995 50hp) and it never idled down well enough for me. The older motor uses more fuel but runs so much sweeter for my usage.
Jim

I have a '96 Merc. 50 2cy that I troll all day with.
I have to give it gas to get up to 1.8mph for trolling on Lake Erie for walleyes, and steelhead.
What I did was down size the prop pitch. They usually run with a 13 pitch, and I run a 11 pitch. It idle/trolls at about 700rpm, and I have to get it up to about 900 to go 1.8 (more against the wind). I guess I'm lucky, my 50 runs smooth and quiet.
You loose about 2 mph on the high end, but I'm not a speed demon anyways. With the waves on Erie your lucky to run anything above 20mph without busting a gut, or your boat.
Top speed on mine with the 11 pitch is 29 or 30mph.
I always open it up when going back to the dock to clear out any carbon build up, and try to run real gas (no 10% ethanol) 100% of the time + Staybil.

Works for me...

I like your fishing buddy.

FWIW, I have a two stroke 1996 Merc 115 four cylinder on on my 19' Starcraft Deep V. It cuts back to two cylinders at an idle. I used to troll with it day after day, all day long. I have a 7.5 HP Honda four stroke long shaft, now.

The 115 sounds kind of like a John Deere tractor at idle.