The Stovebolt Site Forums The Shop Area Engine Shop Still carb issues, 55 235

Still having choke problems. But first let me be more specific. After spending most of the day researching the internet, I believe that what I have is a Rochester BC carb, not B. This means that there is a chokerod that links the throttle valve to the choke valve (not a stamped metal plate), and this rod must be bent to the correct adjustment. I am hoping to get confirmation that I understand the procedure, as follows.

The Rochester Service Manual, from Deves TechNet states:
1. With the choke cover properly indexed [I assume that means the spring should under enough tension to fully close the choke valve, at room temperature] turn the idle screw in until it contacts the second step on the fast idle cam as shown in figure 2-22 [not a very good image].
2. Holding the screw tightly against the shoulder of the high step of the cam, bend the chokerod at the dog leg to obtain the specified clearance [5/64", according the sheet from my carb rebuild kit]between the lower edge of the choke valve and the bore of the carburetor air horn.

I guess that I have to manually move the fast idle cam between the two steps reference in steps 1 and 2, and that all this is done with a cold engine.

Any further elucidation would be very welcome. I hate auto chokes!

Bob

Bob,

There were/are a few styles of BC carburetors.

Here are some manuals/etc for a few.

Elucidation?! Hey buddy, this is a family friendly site. Take your foul language elsewhere Mr!
On a serious note (I do have those every once in a while), I am with you on the auto choke hate parade.
Does your setup have a heat box on the exhaust manifold for heating up the choke coil?
If you continue to have issues after adjusting according to the specifications in the manual, you may have a bad or incorrect bi-metallic spring.
Try is to adjust by dialing the choke spring after the engine is fully warmed up. (This is contrary to what the manual says, but bear with me for now).
Turn the choke spring housing counter-clockwise until it no longer affects the position of the choke plate (engine warmed up).
Wait until the next day, with the engine cold to see if the spring closes the choke.
Start the engine until the engine warms up to see if the spring moves so that the choke gradually opens as the engine warms up.
If it doesn't, dial back the choke spring housing a bit to put less tension on the choke plate so it will open sooner.
Carl