Itinerant Air-Cooled

Amskeptic wrote:

Sylvester wrote: Adjust the screw on the top of throttle lever so that it just touches the fast idle cam.
Then turn it in 1/4 turn.
Note: This step is very important. It opens the throttle butterfly in the carburetor 0.004" so that the idle jet will work properly.

That would be true for the PDSIT dual carb buses.
The 34Pict3 I believe, needs a .020-.040 gap between the screw and the fast idle cam?
Colin

I will look this weekend, this is my stay at home and get crap done weekend. Also when I start I am easily at 1900 RPM, when the Bus is warmed up I go to 1600RPM. Still nice not for Sam to die at stops. HOWEVER:

I want to adjust the carb but don't want to start from scratch, or should I anyway? Or just go from where I am? I mean, I don't want to screw down the volume control all the way down and back it off 2-3 turns.

Sylvester wrote: I want to adjust the carb but don't want to start from scratch, or should I anyway? Or just go from where I am? I mean, I don't want to screw down the volume control all the way down and back it off 2-3 turns.

Don't do it from "scratch". Bottoming out the mixture screw broaches the claibrated circle at the end. You only do the scratch after an overhaul.
You orient yourself by doing the lean drop, Cw on the mixture screw to drop the idle speed due to initial fuel starvation (do not get yourself confused with the idle speed screw! just because I am mentioning a speed drop doesn't mean we are talking about the speed screw!), then back out CCW to best idle achievable. Add a quarter turn richer.
Now adjust adjust idle speed with the big screw to 950-1,000 rpm.
That's it.
Colin

Amskeptic wrote:

Sylvester wrote: I want to adjust the carb but don't want to start from scratch, or should I anyway? Or just go from where I am? I mean, I don't want to screw down the volume control all the way down and back it off 2-3 turns.

Don't do it from "scratch". Bottoming out the mixture screw broaches the claibrated circle at the end. You only do the scratch after an overhaul.
You orient yourself by doing the lean drop, Cw on the mixture screw to drop the idle speed due to initial fuel starvation (do not get yourself confused with the idle speed screw! just because I am mentioning a speed drop doesn't mean we are talking about the speed screw!), then back out CCW to best idle achievable. Add a quarter turn richer.
Now adjust adjust idle speed with the big screw to 950-1,000 rpm.
That's it.
Colin

I have adjusted twice just as mentioned above. For some reason I get a good idle at 1200 rpm, anything else is no idle die.

Sylvester wrote: I have adjusted twice just as mentioned above. For some reason I get a good idle at 1200 rpm, anything else is no idle die.

Better check that idle solenoid. Make sure it is clicking and retracting properly.
ColinWashingtonDC

Amskeptic wrote:

Sylvester wrote: I have adjusted twice just as mentioned above. For some reason I get a good idle at 1200 rpm, anything else is no idle die.

Better check that idle solenoid. Make sure it is clicking and retracting properly.
ColinWashingtonDC

Bah! This morning after warm up I get 2000-1800 RPM again, like I never adjusted it at all. I hope I have not hit another carburetor anomaly, although it very well may be me, heh.

Sylvester wrote:

Amskeptic wrote:

Sylvester wrote: I have adjusted twice just as mentioned above. For some reason I get a good idle at 1200 rpm, anything else is no idle die.

Better check that idle solenoid. Make sure it is clicking and retracting properly.
ColinWashingtonDC

Bah! This morning after warm up I get 2000-1800 RPM again, like I never adjusted it at all. I hope I have not hit another carburetor anomaly, although it very well may be me, heh.

Git in there and look boy. Is throttle lever fully closed with the little screw on top NOT touching the fast idle cam? Is the accelerator pedal getting weird again?
And remember, electrical solenoids often work well when cold and die when hot.
ColinAnomalizeThis