Home › Forum › Ask A Member › 1966 Evinrude Lightwin 3 hp
- This topic has 9 replies, 9 voices, and was last updated 9 years, 6 months ago by The Boat House.
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May 27, 2015 at 5:37 pm #1616
I just got this motor running after replacing the powerhead. It seems to run lean if you move the gas too fast it will die, pulling the choke will get it going.This is the fixed high speed jet type carb. The fixed jet was stopped up and I used a safety pin to clear it. The idle passage was also clogged after soaking in carb cleaner its opened up. I also removed the idle jet plug and blew out chamber. Them resealed the plug. The float looks level with base when closed. The motor will idle slow at about 1 1/4 turns on idle mix screw. Also the fuel flow from tank is good. Do you think the fixed jet is the problem ?
May 27, 2015 at 6:59 pm #17037Yes. That is a precision hole and must be absolutely CLEAN. Even a trace of varnish or crud will cause enough restriction to make it lean. Some guys get away with shoving wires and drills & stuff through them, but I cringe at that. Like I said it is a precision hole.
May 28, 2015 at 11:46 am #17062I use a pipe cleaner dipped in carburetor cleaner for the higher HP fixed jet outboards. It does not damage the metal like welding tip reamers can. For my personal outboards, I install an adjustable needle valve kit. They can then be used at high altitudes without worry. Pipe cleaners used to be available at drug stores, but now are found only at smoke shops. Many hobby shops have them in assorted colors and shapes.
May 28, 2015 at 11:57 am #17065Yeah, I like the pipe cleaner method as well. But, it is tough finding a small enough pipe cleaner to fit in the fixed jet of the smaller engines.
May 28, 2015 at 2:35 pm #17079quote FrankR:Like I said it is a precision hole.Boy; I guess so. When you think of how much difference just a **LITTLE** adjustment does on the carbs with the adjustable High-Speed jets…..imagine how precise that little hole needs to be.
I imagine that in many a carburetor….that fixed jet is "cleaned" with a wire or whatnot….and that engine will run rich from that day forward. I personally don’t like the fixed jets.
I’ve found that the "simple-green" sort of cleaner (mine is the Costco equivalent) works very well for such endeavors. Just soak the pieces in there (I heat the solution a bit) and everything comes out bright and shiny. Very quickly too.
May 28, 2015 at 3:43 pm #17082If the jets were plugged, there’s a good chance the fuel line and filter may be to. If they have any crud in them restricting the fuel flow, the bowl wont fill up properly and this will give a lean running condition. This is a common problem on all the three horse motors.
May 28, 2015 at 9:38 pm #17107make certain the 2 little vent holes Under the vent screw (gaz cap) are not crudded over. unscrewing the vent won’t help if the two holes are crudded over
You must see light in the 2 small vent holes. (paper clip works nice)Joining AOMCI has priviledges 🙂
May 29, 2015 at 1:00 am #17118When I pull the gas hose off the carb I get a good stream of fuel. And when you remove the plug in front of jet fuel flow out.
May 29, 2015 at 2:28 am #17123I have never owned one of those 3hps with the fixed jet that are anything but "sluggish" when you open the throttle.I have washed ,set ,scrubbed and reset every conceivable part of those carbs and still the motors with the two needles always run better .Don’t know why but if you find out please let me know.
May 29, 2015 at 12:12 pm #17131- This reply was modified 6 years ago by The Boat House.
- This reply was modified 3 years, 9 months ago by The Boat House.
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