Welcome! Need support, you got it. Or share you ideas and experiences.
Knowing very little about how too fine tune or trouble shoot my outboard very well, I pose the following question. I have a 69 6hp Evinrude. It starts fine, and runs great from about 15% throtle too 100%. However, It stals instead of idleing, It vibrates and runs rough in this low 15% throtle area but does not stall, there is 1 spot around 5% throtle that it runs smooth at low rpm however it starts to foul the plug after 10 min or so requireing me to open it up a bit to clean them off. This motor also seams to kick into what would seam like a powerband just over 15% throtle, the engien jumps drasticaly in RMP and noise level, as well as forward speed at that point with just the littlest additional throttle, then runs smooth up too max throtle. I generaly dont troll with it, But it bothers me just a little that I cant if I wanted too. The boat does have a electric on it for troling.
the motor has been like this since I got it last year. the fouling thing seems to have gotten worse as the season progresed, but it never left me anywhere or made me pull the pluggs, throtling up for a bit restored low speed ability again for a little wile. I mix 50-1 high grade gas. The rough running at low speed stayed the same from fresh plugs through the season.
The water discharge is not as heavy as It should be however it is never too hot too touch, not even close. It probabley has nothing to do with the idle but it is something slightly abnormal. I also noticed that throtle postion makes no diference to water flow, its always constant. shouldnt it be more at speed?
Some fouling is to be expected at low speeds. However there should be a screw for idle speed adjustment on the throttle linkage arm inside the case. It will be a fairly large screw that hits a stop when the throttle is turned and released. Turn it in to increase Idle speed do this with the motor running. Run the best grade of oil you can find to decrease fouling at low speed.Maybe a little colder plug would help also. Just a thought. Also the water comming from the tattle tale just lets you know that the pump is working. most of the water is actually returned under water out the foot.
any ideas on the rough running in the low area of the throttle? WHen I say rough, I mean the whole engien shimmies and shakes
Sounds like you need to tinker with the idle mixture screw.It is located on the side or bottom of the carb depending on the model. It will be a small brass screw with a spring around the shaft of the screw. proper adjustment is as follows. with engine idling, gently turn screw inward very slowly. If engine runs rougher, turn the screw the other way do this very slowly til the engine runs smooth. Also bear in mind that some two strokes will simply not idle smoothly at very low speeds.
ok, thanks, In not too good with motors from a repair standpoint, As long as its running I can adapt anything I want, but if it dies,, Im screwed hehehe..
Ken, These small motors are not hard to understand. The proper way to adjust the idle adjustment screw Is very simple. Lets assume that you have had the carb completely off the engine. Let's say that this was done for a carb rebuild. What you would have is a totally un adjusted fuel mixture. the proper procedure would be simply: turn the idle screw in til you feel it seat gently. then turn the screw counter clockwise 1 and 1/2 turns. crank the motor. then turn the screw out until the motor runs smooth. simple enough. You are not screwed at all HE HE HE! Good luck, TG
OK thanks TG, Ill take a crack at it this spring, as soon as my workshop is accesable, RIght now my boat is occupieing it, and it has 3 feet of snow all around hehehe. I am planning on building a small speedboat looking thing for my nephew. roughly 8x4 and I plan on mating that to this 6 hp, so I really want to get it as close to perfect as I can. For me, It was good enough,, but, For my Nephew, It has to be in good shape or I wouldnt feel comfortable letting him drive it. He will prob never get to use it unless Im there in my boat anyway, but that is besides the point and probably the begining of a whole nother thread of conversation. Perhaps Ill post something on this a little later. right now, I just has a rough design of the shape size and placement of things. I'm curently working on the structure, trying to decide what will be enough. It will definitly be built for strenth. and completely reinforced with fiberglass. ( buying a plan is too easy, I wish to create from scratch )
I want to see photos of that speed boat if you build it, sounds cool. I have an old honda mt250 motorcycle that had some carb trouble. The shop guy was explaining to me that there were 2 or maybe three fuel jets in there. One is the idle jet, they are really sensitive to gumming up if the motor is not used on a regualar basis and also sensitive to height above sea level, like the rockies you would need to use a larger idle jet (or vice versa I cant remember). Did this motor come from a place that has a large difference in altitude from you?
As Far as I know, it came from around here.. It is more likely a screw setting like TG suggested then anything else. the person I got it from wasnt exaxtly teh most maintnece minded or careing of the equipment. The boat it came with had a sofwall sized hole in the bottom that he tried to fix with ordinairy car bondo hehe. The props pretty beat too, but to my amazement, even though it is not propery shaped anymore, It does seam to spin balenced. Hmm,, On that Note, I wonder if the prop has something to do with the rough running.. It really looks and feels & sounds like its the engien though, dosent seam to have anything to do with the lower unit or prop. As Far as my boat, Ill post some on it later. My father was a Aircraft design engienere, and I am going to visit him in a few weeks out of state He is also a avid boat owner and very mechanical. After talking with him, I am sure I will change my design some. I have some ideas on what I concider to be the optimal shape verses easiest too build. anyway, Ill get into that next month when I get back.,,, Eventualy,,, when I get back Fishing season will be 9 days old, SO getting my new motor ready and the boat in the water will prob take a good deal of my attention. Boating Feaver strikes
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