2009 Buddy 125 erratic idle

Bill61 · Post by **Bill61** » Sat Jul 20, 2019 10:20 pm

The problem is the engine will not return to idle quickly after blipping throttle. Stays at a higher rpm then slowly returns to idle. Impossible to set idle correctly. Checked diaphragm, #3, no holes, installed correctly.
Carb has been thoroughly cleaned.

ucandoit · Post by **ucandoit** » Sun Jul 21, 2019 2:12 am

Is there a chance that the throttle cable is sticking a bit? It can be cleaned, if that is the case.

Bill61 · Post by **Bill61** » Sun Jul 21, 2019 2:20 am

Checked the cable and attaching parts on carb. Lubed all, functions as it should.

babblefish · Post by **babblefish** » Sun Jul 21, 2019 5:58 am

Sounds like the diaphragm is taking it's time returning to the bottom of it's travel. The diaphragm return spring is in place, right?

Bill61 · Post by **Bill61** » Sun Jul 21, 2019 3:46 pm

Yes the return spring is in place. Took it apart, reassembled per parts diagram. Everything looked good.

Bill61 · Post by **Bill61** » Sun Jul 21, 2019 4:02 pm

I did notice that the bowl vent tubing is missing. Don't see how that would affect anything though.

Stanza · Post by **Stanza** » Mon Jul 22, 2019 2:40 pm

That's your problem. The vent tube on the bowl (smallish? elbow shaped?) is actually part of an emissions circuit, which is a straight shot up into the bore of the carb. It's allowing a vacuum leak, if it's just breathing air freely. Plug that vent tube with a rubber cap, or a bit of hose that's folded over and zip tied. Your idle should go back to normal.

Bill61 · Post by **Bill61** » Tue Jul 23, 2019 12:07 am

Would not run with vent plugged. Good news: pilot jet plugged. Could not unplug, soaked in carb cleaner, used jet cleaning tool, no go. #38, where to buy a new one?

Stanza · Post by **Stanza** » Tue Jul 23, 2019 2:54 am

Would not run with that plugged, because your pilot jet is gummed up. Clean the jet with an ultrasonic and compressed air if you have access. If not, a new one will fix the fuel delivery, and plugging that vent tube will correct the vacuum leak.