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All of the sudden it bogs down at WOT

newyota

Regular Contributor
I have this 20crcos 1985 tiller rope start that this summer gave me some fits, but after repairs were made(fuel pump rebuild,Lead shot for idle circuit repaired and carb passage cleared and lync sync checked and spark verified and new primer bulb,Vacuum leaks on lines to carb. and manifold.) I had it running better than ever.Able to idle down with no issues and starting no issues.Put tiny tach on it also and running 6k at WOT.All seemed perfect.Now out of the blue it wants to just go "blah" for lack of better words at WOT.At first I panicked and thought it was jumping out of gear, but rpms would increase and a loud clunking in and out of gear would ensue if I am not mistaken.It does not stall right away or not at all since I will throttle it down right away also and I just back off on throttle for alittle and go again.I tried the squezzing the primer bulb thing before I tried reving it up and did not notice any increase in rpm(maybe I did not wait long enough?) so I just waited a tiny bit at low rpm then took off again.Seems kinda random as far as how long I go till it happens.Does this sound like maybe a sticking float needle and or maybe I may be sucking air and not getting fuel enough in general?
 
Is your wife standing on the fuel hose?
Seriously, it is a fuel supply issue. Maybe some crap in the tank?
 
I came across a supply line/hose.......the grey, plastic composition type, that the inside layer delaminated, intermittently plugging/restricting fuel flow right before the motor coupling. I should really post a picture of it in the ethanol posts. It was a miracle that I found the problem so quickly. When Trump pumps ethanol to 15 percent, our marine repair business will really boom. Already, I thank ethanol for nearly 1/2 of my repair work. Stabil, or any additive, cannot eliminate the long term destruction caused by "moonshine".
 
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I'm having the same issues on a 1966 Evinrude 80hp Starflite. I used 10% ethanol gas. Was told to check the diaphragm in the fuel pump for hardening up, which cause flaking and a porous fuel leak. Can anyone tell me if the available rubber diaphragms for these fuel pumps are all pre ethanol. I'm assuming the ethanol is to blame with my issue.
 
Yep, plan on it Racerone. Anything in the carb or ok elsewhere I should replace since it's been exposed to ethanol? I will only be using non-ethanol from now on.
 
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