Topic: Tip of air/idle screw broke off in hole...77 750F

[Lumbee]

...so now its blocked.  I know that cylinder is gonna run rich, but whats you guys opinion on how long I can run it this way.  For a season, then worry aobut it in the fall, or do you think I'll foul a plug before then?

[crazypj]

Its going to run lean with the tip stuck in the hole. You should be able to push it out after you take the carbs off.
PJ

[Lumbee]

FYI is a 77 750F...i thought turning the screw in removes the air therefore richening the mixture.

[TwoTired]

The 77 and 78 carbs have an Idle Mixture Screw.  It adjusts the fuel/air mix coming from the slow circuit (air and slow jets) in total.  If the mixture screw was over tightened and broke off at the exit hole, no fuel air mix is going to make it into the carb throat, and the engine will run lean.  I don't think it will idle on the that cylinder either, because the idle/slow circuit is now shut off entirely.

Go ahead and run it.  If you like the SOHC3 sound and performance at idle, and a crispy single spark plug.

[scondon]

    TT's right. The screw meters fuel, screwing it in makes it leaner, all the way in shuts it off. If the needle tip is in the hole and you back the screw out then you may get fuel to flow, but with the tip just "floating" around I imagine that it would run pretty inconsistently.

   Just looked on Powersportspro(expensive) and see the screw,spring,washer,o-ring listed at $11.64. If Honda still sells the part it would be worth your peace of mind.

[Lumbee]

...hmm...so does in the IN=Lean Out=Rich apply to the 69-76 models also?

[scondon]

...hmm...so does in the IN=Lean Out=Rich apply to the 69-76 models also?

No. For earlier carbs the reverse is true. It's been said here before, but to repeat, mixture screws on the air intake side of carbs regulate the amount of air(fuel is constant). Screws on the engine side of carbs(like yours) regulate amount of fuel(air is constant).

[Lumbee]

..ahh (the clouds just parted I think).  So on the earlier carbs, the screw is on the airbox side (don't have any exp. with earlier carbs).  Makes sence...

...yea, the bugger broke off in there, and its gonna have to be drilled out, I sewing needle is the only thing I could find small enought, and it breaks when I try to push it out the other side.  Gonna have to find a drill bit small enough to drill it out...

[TwoTired]

Well, that's a metered orifice.  The more buggared that finely tappered hole becomes, the more unlikely it can remain a controlable metering mechanism.  Better start shopping for another carb body if you can't drive it out cleanly.

Good luck!

[Lumbee]

...yea, thats why I'll need to drive it out from the smallest end, that way it was hose the taper up...

[dusterdude]

good god,you go to mytle beach for a week and come back all screwed up.

[6adan]

If you find a way to get that little tip out please let me know I have the same problem on a 81 750K. Thanks Dannie

[jtb]

Lumbee, which carb?  I may have an extra body with the idle screw.
John

[Lumbee]

#2 carb with Accel pump/choke spring...lemmie know what ya got...

[jtb]

Got the #2 body.  Do you need the bowl, slider and other stuff?  I can probably dig that up too.

[Lumbee]

...u da man JTB...u'v got PM...