Hi guys, I bought a 1992 Mariner 15 HP 2-stroke outboard for a deal, but I am starting to wonder if the "deal" was good or not now. When I got it, it came with a crusty old tank, and the tank line and the carb was full of crap. (see pic)
I drained the gas tank, made fresh gas (50:1) exactly, bought new fuel lines, and installed a mesh fuel filter in-line. Next I ordered a carb kit and cleaned and completely rebuilt the carb. It starts right up and idles pretty good.
Next, I gave it the Seafoam engine treatment. Idled to warm up, then poured 1/4 can of Seafoam in the carb and turned it off. Waited 10 min, then started it up and ran it for a good 30 minutes to clear all of the smoke out of it. Smoked like crazy. Next, 2 new spark plugs.
My problem now, is that the outboard runs pretty rough when I have it in gear, and especially when I try to rev past 1/2 throttle. It REALLY smokes, and shakes a lot. So much that I haven't had it up to full throttle yet. I've tried adjusting the mixture screw, and I think that I have it set right. I do have about 1 oz of Sea Foam in the gas per gal to help clean things out. It still smokes a ton when in gear. I have been around 2-strokes all my life and they never smoked like this one does. I know the fuel mixture is right (50:1). It does start and run on 1 pull.
When I run it in the tank, the tank water gets fouled pretty quick. There are small bits of black floating in the water, and there is usually some brown sludge on the back of the outboard that comes from the exhaust. My new spark plugs already have bits of junk on them. (See pic)
Can you guys tell me what I should check next? Thanks!
I drained the gas tank, made fresh gas (50:1) exactly, bought new fuel lines, and installed a mesh fuel filter in-line. Next I ordered a carb kit and cleaned and completely rebuilt the carb. It starts right up and idles pretty good.
Next, I gave it the Seafoam engine treatment. Idled to warm up, then poured 1/4 can of Seafoam in the carb and turned it off. Waited 10 min, then started it up and ran it for a good 30 minutes to clear all of the smoke out of it. Smoked like crazy. Next, 2 new spark plugs.
My problem now, is that the outboard runs pretty rough when I have it in gear, and especially when I try to rev past 1/2 throttle. It REALLY smokes, and shakes a lot. So much that I haven't had it up to full throttle yet. I've tried adjusting the mixture screw, and I think that I have it set right. I do have about 1 oz of Sea Foam in the gas per gal to help clean things out. It still smokes a ton when in gear. I have been around 2-strokes all my life and they never smoked like this one does. I know the fuel mixture is right (50:1). It does start and run on 1 pull.
When I run it in the tank, the tank water gets fouled pretty quick. There are small bits of black floating in the water, and there is usually some brown sludge on the back of the outboard that comes from the exhaust. My new spark plugs already have bits of junk on them. (See pic)
Can you guys tell me what I should check next? Thanks!