Help! Can anyone tune a merc 2.5 motor by Thursday night???

Put another hour into it tonight and I think it's running as good as I'm going to get it. Doesn't love being at low idle and likes a tiny bit of choke. Good enough. Thanks for all the help guys.
 
Can you just raise the idle rpm? Maybe it’s just too loose on the cable and almost killing it while it’s trying to idle at a super low rpm. It’s not like you’re gonna burn through a ton of gas if you’re idling 100 rpm’s higher. Just gotta pin it to the beach and back for your application
 
Can you just raise the idle rpm? Maybe it’s just too loose on the cable and almost killing it while it’s trying to idle at a super low rpm. It’s not like you’re gonna burn through a ton of gas if you’re idling 100 rpm’s higher. Just gotta pin it to the beach and back for your application
That's what I ended up doing. Just have to sort of kill it before throwing it in gear. These little things are really nice though at their low low idle. A LOT quieter and slower. They jump up quick as soon as they're over a dead idle.
 
I've got a merc 3.5hp 4 stroke and been through this rodeo more than a few times. The low speed jet in these things is small enough they regularly get plugged. You can get it running perfectly again but it takes some work to get rid of the debris. It likely isn't dissolvable. What I have done is removed and cleaned any orifaces with wire and air. Blown every which way with air on the body. But probably the best thing I've done is submerging the completely stripped down carb frame in either carb cleaner or gas in a sealed container. Then I've held that container on an orbital sander for awhile to create a poor mans ultrasonic cleaner. Sometimes takes a few tries but eventually the little particulate will dislodge. PITA putting the carb back in to test only to find still plugged but eventually....

If you haven't already add a better inline fuel filter and keep the gas can clean as a whistle.

Cheers,
Slinger
 
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I just saw these. Relatively inexpensive. Since I own a 3.5 Merc I might have to get one, because apparently they have troublesome carbs. Could use it to clean fishing gear too!!!
 
Well after getting it running and getting it up to Bamfield, the saga continued. Started fine, put it on the inflateable, took a lap around the marina. Few days later I went to mount the rod holders and fill the tank so I pulled it up onto the dock. Unfortunately, when I went to dump it back in, the boat flipped upright standing on its butt. The dock is kind of high. It was only like that for a second. When I jumped in and went to start it, it puked oily looking gas out the exhaust. Reefed on it for over an hour trying to clear things out. Pulled the carb apart...again, made some adjustments. Got it to finally fire but it revs up and dies with a "cuuuuuuhph" and pukes more fuel. Ended up running it up the hill to Breakers and by the sounds of it, they're still getting oil in the fuel. Probably not getting it back until Monday at the earliest. What would cause oil to get in the fuel?
 
It's usually the other way, fuel in crankcase oil, fuel wash cylinders, from running richhhhh
Ah maybe that's what it was. Didn't talk to the mechanic. Just got the purple monkey dishwasher phone relay message from the girl at the desk. Come to think of it, I did notice the oil was bubbling in the little glass looky loo thingy
 
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I always use 94 chevron or ethanol free fuel. Put it away last September. **** off fuel and ram it until it stalled. Chocked it and ram it again. Until it stalled. Fired up on second pull today. So I’m glad I don’t have the small Merc blues, for my upcoming trip.
 
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