150 yamaha idle adjustment

RWilson2526

RWilson2526

God
I had my carbs rebuilt beginning of last season....if you guys remember when I first bought the boat it had what Ferm called a "lean sneeze" took it to the guy that does my engine work and had them rebuilt and sync'd . Engine ran well at all duties accept from the get go it idled very low in neutral in the water....idles at 600-700 in the driveway on the muffs (which is how my mechanic set it up) but in the water it idles at 200-300 rpm in neutral....amazingly at even that low of an RPM it stays running for quite a while usually but will eventually stall. biggest problem of course is when maneuvering around the dock it will frequently stall on me when I dont have the time or need to bump the idle lever up a hair to keep the idle up....

never bothered me terribly because you just deal with it but it is a pain in the *** at times....I'm sure my mechanicc will adjust it for me but he is more than an hour each way to tow....is this something easily adjusted considering I have no outboard engine knowledge at all or should I just suck it up and drag it over to him to take care of....is it something that must be done in the water or can he just bump it up some to compensate for the difference between in the water and out of the water?
 
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Can you post some pics of the carbs and linkage? I don't know where the adjustment is off hand, some is done at the carbs and others are done at the timing linkage.
 
i have a 2003 150 and the idle adj is on the middle carb. with the cowling removed stand over the air shroud and look straight down on the starboard side at the middle carb. should be a phillips screw looking back at you. if you work the butterfly's with your fingers, you will see the one . it might be easier with the air shroud off , but its a pia with 12 screws holding it on.
 
phatdaddy said:
i have a 2003 150 and the idle adj is on the middle carb. with the cowling removed stand over the air shroud and look straight down on the starboard side at the middle carb. should be a phillips screw looking back at you. if you work the butterfly's with your fingers, you will see the one . it might be easier with the air shroud off , but its a pia with 12 screws holding it on.
Click to expand...

I did a little digging and I found that he has an 86 150. It also adjusts with one screw on the center carb just like yours does. And the idle should always be set with the engine in the water at temp and normally to about 600-700 in gear.
 
Thanks guys,heres a picture but it sounds like you have it figured out already....

I'm assuming its the screw thats in the vertical that is only on the middle carb and just tapped holes on the other two? and so will it be just a matter of going out,taking off the cover while idling in gear and just giving a turn slightly until the rpm hit my desired number?

DSCF4474.jpg
 
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rw, in the picture, see the linkage with the black plastic , that is the throttle links. look at the center link and the screw that is verticle and facing up is the idle adjustment. clockwise faster ccw slower
 
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