Helpwith throttle stop screw

[Yamaha3535]

hi there, I have a 2003 Yamaha txrb130. I messed with the throttle stop screw on the lower carb and now boat coughs in neutral and hard to start. Once I get going I have no problems until back in neutral. How should I adjusti that screw back in the right position and getting it to stop cutting off in neutral? Thank you

[TownsendsFJR1300]

What was the initial issue that you messed with it? Idled too high, too low, ?

What is the idle RPM NOW in neutral?


Sounds like it's currently set too low. Turning the throttle stop screw clockwise, raises the idle.

[99yam40]

service manual should have the link and sync procedure

[Yamaha3535]

The day I messed with it it kept stalling and I went thru everything and for dumb reason I listen to a friend who said it sounded like it was idiling to low. Then later when I got home realized that was pretty stupid. In neutral it’s about 750-800. When you mess with that screw does the carbs sync get outta wack or the throttle roller plastic piece?

[99yam40]

if the motor was having a problem even before you messed with that screw, you probably need to clean the carbs.

the cough you speak of is more than likely a lean sneeze

[TownsendsFJR1300]

Some history please on the engine, IE,

Did it sit for any length of time?

Is it new to you?

Did any service work ben done to it recently?.

Have you tried draining the carbs and catching what comes out?
You want to be looking for any crap, water, etc. Prime the bulb to push fuel thru..


As noted above, you may need a carb cleaning, especially if you use Ethanol fuel W/O stabilizer






.

[Jason2tpa]

Idle speed screw alters "speed", aka rpms. This screw would be the last adjustment you make to timing and syncing carbs, if its adjustment is needed at all....essentially it's used to fine tune the idle rpms up/down after having already adjusted air screws for a smooth idle.

Since you're only experiencing a cold start issue, I'm wondering whether the fuel enrichment solenoid is functioning. See photo...solenoid is highlight yellow. The pull wire extends from solenoid and slides over the carb throttle lever arm. When you push in the ignition key, this solenoid activates causing the pull wire to pull up, which in turn pulls the carb throttle arm up, which in turn closes the carb throat (butterfly's), which enriches the fuel being used to fire up the engine. Check this solenoid not only functioning (open cowling and watch pull wire activate as you simultaneously push ignition key in), but also be sure the end of this pull wire is engaged w/the carb throttle lever arm.

[Yamaha3535]

Yes the boat has sat for a lot longer then usual. I do use ethanol fuel as that’s all I have around me. Whenever it sits I have problems. I actually didn’t know stabilizer would help prevent that(meanwhile I have two bottles t the house). I did push all the fuel out the day I was having problems but didn’t catch what came out. I’ve had the boat for 6 years and haven’t had any service done. I would imagine the carbs need to be cleaned out would be my best bet. The solenoid you speak about does activate the choke when I push I the key as I can hear it.how long does it take for ethanol fuel to sit to go bad? It seems not very long, I try and get to marina to start if I don’t use the boat but it’s not close to me.

[TownsendsFJR1300]

Ethanol fuel un-treated will clog up a carb in as quick as a month.

At this point, you likely need them physically taken apart and cleaned.

I use two products that keep ethanol fuel good for easily a year. "Gas Shok" (got it at the Yamaha shop, recommended by them-works REALLY WELL).

Yamaha also makes a stabilizer, can't speak to how well that works.

For the boat, I use K100 (with Non ethanol)