1986, 140 Evinrude Acceleration

[seaya]

Hopefully some of you can help me. The engine runs well at idle and at higher RPM's. But when I try to accelerate (above 3,500 RPM), the engine hesitates and can not throttle up. After waiting a minute or two, most of the time it eventually gets over the hump and runs well. I have changed the plugs, fuel filter, rebuilt the carbs, checked all fuel lines, compression, and verified that the fuel pump is operating properly. I am beggining to think the problem is related to something electrical, possibly a faulty stator, powerpack, ignition coils. Any ideas ?

 

[Dhadley]

Re: 1986, 140 Evinrude Acceleration

Which spark plugs? What fuel? What oil? What ratio? Air box on or off? When you did the carbs did you set the floats to the correct height? Are you sure you put the idle and mid range jets back correctly?<br /><br />Tell us more about your rig. Top RPM's, what kind of hull etc?<br /><br />Good luck!

 

[Brew]

Re: 1986, 140 Evinrude Acceleration

Sorry, I don't have the magic answer, but I can co-miserate. I have the exact same motor with essentially the same problem.<br /><br />I've made strides in correcting the problem by doing basically everything you have done (ie. it runs better now than it used to, however, still not great).<br /><br />Just replaced all my fuel line, but haven't taken it out on the water yet.<br /><br />One thing you might want to double check are the plastic tubes that run from the carb float chamber to the carb barrel. The plastic was disentigrating on mine (ie. tube was getting shorter and shorter). Unfortunately getting factory tubes proved to be impossible (they want you to buy the entire carb!), so I had to make due with some similar tubing from a hose distributor.<br /><br />Good luck, and please let us (me) know if you find the answer. I'll do likewise.<br /><br />Cheers.