Where are my high speed orfaces and low speed orfaces on my 90 hp johnson?

scottye

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Mar 20, 2014
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I cleaned the carburetors out with compressed air and carb cleaner got the boat running but bogging down and sputtering before plane. It broke loose finally and took off for 30 seconds or so when i had to slow down to take a turn. When i accelerated again it bogged down and died. Went home cleaned carbs again. Took two screws out that i hadnt before on the side of the bowl at the bottom. (One on each side). Inside were two much smaller screws that were deep in the housing that i took out with a really small screwdriver. They were completely closed. Are these my high speed orfaces? If so then how should they be adjusted? Also the orface (seat) that the pin goes into in the float chamber; is that my low speed orface? How should it be adjusted? It is also tightened. I feel like having these orfaces completely tight is restricting my gas flow to the point that I cant sit in idle without the cold start lever up. Sorry for long post....thanks in advance for the help!
 

racerone

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Dec 28, 2013
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36,260
Re: Where are my high speed orfaces and low speed orfaces on my 90 hp johnson?

An orifice has a calibrated hole.----This is what meters the amount of fuel that goes into the air / fuel mixture.---The orifice is not adjustable and needs to be in tight !
 

scottye

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Mar 20, 2014
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Re: Where are my high speed orfaces and low speed orfaces on my 90 hp johnson?

Hey racerone thanks for the reply. Maybe im using the wrong terminology, although the diagrams ive seen suggest that im not. What i need to know is how do i adjust my high speed and low speed jets/valves? Its a matter of turning a couple screws in our out a bit on my previous motor but i dont know where they are on this one. My motor will start with my cold start lever up but when i put it down my motor dies thus not able to put it in gear and go. Obviously this is a fuel issue. I have a primer solenoid which is in the auto position with the red tab facing the solenoid. It is working. How about the seat that my float pin goes into. Should it be tight as well or turned open a bit? THANKS FOR THE HELP
 

racerone

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Joined
Dec 28, 2013
Messages
36,260
Re: Where are my high speed orfaces and low speed orfaces on my 90 hp johnson?

No motor model # posted.------Well , the high speed jets are NOT adjustable !!!!!!!!!!!---Likely the low speed jets are NOT adjustable---The orifice is screwed in tight.---Float valve should be tight as well !------Look for other issues with the motor.-Start with a compression test.
 
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