95 Mariner, 25hp carb issue - need help

10 years ago I lost a 25hp mariner off the back of my boat. This spring I found the motor (totally by accident)and have managed to get the motor running! The only issue I'm having is a MAJOR rich condition at idle. At full speed it runs flawless. <br /><br /> I bought a gasket kit for my carb (WMC 45)and have spent hours cleaning it up, I feel that my problem might be an internal carb issue but I really need more opinions. So far I have checked the timing, adjusted the float, checked the reeds, new plugs and set the idle screw back 1.5 turns (from seated) The only way I can keep the motor idleing is too open the butterfly up, when I set the mixture screw and idle set screw to factory it stalls. ANY help you may have would be greatly appreciated!

Re: 95 Mariner, 25hp carb issue - need help

If you have spark to both cyls,and you have good compression, you have a fuel issue. You will need to take the carb completely apart and blow every passage out.<br /><br />You will have to tell us the story of loosing this thing and finding it 10 years later. I would assume it wasn't lost into a body of water but rather a rural ditch or something. Cmon, I'm dying to hear this story!!

Re: 95 Mariner, 25hp carb issue - need help

Yeah, you can't just leave us hanging like that. I mean c'mon..LOL.<br /><br />Dave..

Re: 95 Mariner, 25hp carb issue - need help

The motor was stolen off the back of my boat in 1995. It was bolted, locked and chained. The thief actually cut my transom to get the motor off. <br /><br /> I was out fishing this spring in my canoe and looked down and saw the transom clamps sticking up. It was about 300yards from my dock straight out. I'm assuming that either the thieves dumped it overboard because someone was coming their way or they lost it overboard when they took off. The lake has an exremely muddy bottom with zebra mussels. Besides some cowl damage there is very little wrong with the motor. The prop was pitted, the recoil spring was shot and the carb needs some TLC, besides that it runs mint. Even the water pump works!

Re: 95 Mariner, 25hp carb issue - need help

Some things I forgot to mention... When I check my plugs they are really black, coated in fuel and oil. Also, when I turn my idle mixture screw all the way in (fully seated) my idle comes up a little bit but not enough to make it stop stalling when my idle set screw is where it should be. On a 14ft Legend aluminum boat I'm running 30mph full out even with a crappy prop.

Re: 95 Mariner, 25hp carb issue - need help

Check the float setting. It maybe staying open or sticking in the open position. Good luck and what a story.

Re: 95 Mariner, 25hp carb issue - need help

Under water for 10 years?...and still runs!<br />Ya gotta love them Mercs/Mariners. You should send this story to the factory people as a testimonial. I got an '88 25 and it's been under water a couple times times,(boat sunk at the dock) but it's never been under for very long because I always pull it out soon. Next time...hell...I'll just leave it....won't hurt nothin'.

Re: 95 Mariner, 25hp carb issue - need help

Maybe Mercury will reward me with a brand new carb when they here the story! Thanks for everyones suggestions

Re: 95 Mariner, 25hp carb issue - need help

Do you think you can get it serviced under the original service contract?