Yamaha 90 Carb Pilot Screws

[Popeye 17]

Hello,<br /> This is a 1997. I have Sealoc repair manual. The book lists the pilot screws as 1.25 turns out. But it only lists the center carb. The upper and lower are left blank. All the same or just the center? Confused!<br /> Thanks in advance,<br /> Mark

 

[Capt Ken]

Re: Yamaha 90 Carb Pilot Screws

I've never seen Yamaha list any of the air screws at 1.25 turns out. Usually one side is 7/8 +/- 1/4 and the other side is 3/4 +/- 1/4. Anyway, 1.25 still isn't enough to make a difference. Fire it up, let it warm up, drop it in gear and adjust away. Use a tank of course for running in gear.

 

[Popeye 17]

Re: Yamaha 90 Carb Pilot Screws

Thanks Ken,<br /> I put it in a livestock watering tank an have it running pretty smooth now.<br /> Thanks again,<br /> Mark

 

[Capt Ken]

Re: Yamaha 90 Carb Pilot Screws

OK, I screwed up. Wasn't thinking the other nite when I posted my answer. Had V4 on my mind. The three cylinder 90 is listed as 1 1/4 +- 1/4. Glad its running better and the only way you can be sure its running correctly is the way you are doing it, in the tank. Without that backpressure, you ain't got nothing.