Fuel Delivery to 1 carb??

[bowhunter83]

I have a '91 Evinrude 48SPL......its a 2cyl. The motor starts and runs rough at idle. I have good spark. And the No 1 Cyl is the prob. When I spray fuel out of a bottle into the No 1 Carb, the rpm's kick up and it runs fine, but when I stop spraying the rpm's cut down and it runs rough again. There is fuel getting to the carb because I've checked the drain on the bowl and the bowl has fuel in it, but its not getting into the cyl. Both cyl have intake compression b/c I can cover the carbs with my hand and feel the vaccum. AND both cyl have good internal compression, they checked out with No 1= 120psi and No 2=110psi........I just rebuilt the carbs a few days ago because it was doing the same thing before I rebuilt them......when I had them apart I checked the pickup tube and it was clear and unobstructed.........is this a low speed needle valve out of adjustment or something else?????? And when I took the carbs off, I checked the reed valves and all of them seem to be working fine and in great condition...Any help is greatly apreciated

 

[bowhunter83]

Re: Fuel Delivery to 1 carb??

OK, Ive messed with the carbs a little today. Played with the inlet needle valve on both carbs, it seems to run better,(at idle with ears) but still running rough, I guess I havent found that sweet spot for either of the needle valves yet. It sounds fine when i rotate the butterflies just a hair, the motor sounds better and doesnt sound sputtery, but the rpm's are a little higher than I'd like it to be at idle. Also, when standing next to the motor while its running (on the starboard side) I can hear a hissing sound, sounds like it comming from the carbs? Is this normal?......Also in case anyone else was wondering....when I rebuilt the carbs the manual told me to seat the needle valve and then turn it out 2 3/4 turns....aparently that was WAY too much, I had to screw it all the way in and back it out only 1/2 turn to even get it to start after the rebuild....Any idead on the rough idle would be apreciated. I've checked the spark on each cyl and now when I pull the No 2 plug the rpm's cut down a hair and when I pull the boot off the No 1 Carb it takes a second but then slowly cuts off completely...the exact opposite of what it was doing before