I own a early 90s 25 2stroke merc. She runs a little rough but not to bad but the problem is I am loosing gas out of the side of the carb. While its running you can watch it drip out. Has anyone else ever had this problem.. It has sorta grounded me the last few days and I am hoping I dont have to rebuild the carb 
either a bad gasket or stuck float being that it is running bad……….Yep, time to rebuild!!!!
You should be able to pick up a rebuild kit for about $75. It is fairly basic if you have ever done any of them before. Get yourself a maintenance manual and all the required info and steps will be in there!
Thanks Gary.. Thats what I was thinking 
Sure would be a nice day to take her down to the river
$75?? Is that right? I purchased OEM rebuild kits for a 50hp merc that were less than $15 each. I probably paid list price because I was in a hurry.
“IF” it is just a leaky gasket, that is all that would be required to change, however 99% of the time, when you replace one gasket, you are going to have to do others……
Your best bet is to rebuild. That way, you have peace of mind.
I just checked and it is 73.50 for the rebuild kit. If it solves my problem its worth it. I almost pay that much to pull it up north and to have it not running good can kill a weekend…… Wont be much else to do but 
Is it leaking from the carb or the fuel pump diaphram below it? I have a 25 hp Merc that did that and I sment like $15 for the new diaphram. Just a thought.
Dan
I believe it is the diaphram below that is leaking. I know it will kick some gas from the hole below the blue knob when I shut the motor off. It also looks like that is where its leaking. I thought it may be running down to there from the carb but I just looked agian when I took the pic. My motor starts fine but idles a little rough and I will loose my lower cylinder some times. Same thing happened a couple years ago and some power tune fixed that cylinder problem but it may need it agian.
Here is a side shot of the carb. The diaphram must be the part with the blue knob on top ?
One thing to remember to do is count the turns that the air mix screw is set at. Memorize how many turns it takes to bottom out the screw so you can’t turn it anymore, don’t over tighten it, then when you get ready to start the motor set this screw by how many turns it was set at. Remember to pay attention to 1/8th and 1/16th turns, it makes a diffrence. When its running turn the screw with a screwdriver until it hits top rpm’s at idle, you’ll know, especially because its just been rebuilt and is now clean. I hit top rpm’s then back it off just a little, maybe a 1/16th to a 1/32 of a turn. Its not hard to do just listen to the idle go up and down. Get a good can of carb cleaner spray and run it through all the passages until the whole can is gone, this gets rid of any varnish and deposits that have to be removed, it’ll run like a new one when its been cleaned.
Quote:
Same thing happened a couple years ago and some power tune fixed that cylinder problem but it may need it again.
What’s power tune ?
The Power tune sprays in your cylinder to clean extra carb and oil buildup.. Thats what the dealer told me anyway and it seemed to help.
Thanks guys for the help 
I have never worked on a carb before but have a freind thats going to help. But first I am going to change the diaphram
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