'87 Evinrude 40hp spitting gas out the low idle orifice

[digger658]

Still trying to get it to idle right. Keeps dying at low idle (trolling speed). Run pretty good on muffs but not in the water. Noticed today running on muffs it is spitting gas out of the top carbs low idle orifice. Does this it seems when it sneezes or coughs. Carbs have been rebuilt twice. Took carb off and checked reeve valve and they all seem to be good and holding a seal. I don't think there is any back pressure coming back thru carb.

Any ideas why it would be doing this? The large brass tube in the throat does have a crack in it going from top to almost where it enters the bowl in the bottom of the throat but don't think it's causing the spitting.

 

[fireman57]

Re: '87 Evinrude 40hp spitting gas out the low idle orifice

If you are pulling air through part of this tube instead of fuel it is the same as having a crack in your fuel line and you will pull too much air.If is coughs/sneezes that means you are usually running lean and that is not a good thing as you get less lube to the cylinders. You need to set your idle on the water as it needs the backpressure to work right. You can get real close in a barrel of water.