The Autolite 1100 vent valve is used to vent the float bowl when accelerating, or on power mode, otherwise excess gas will be siphoned into the carburetor bore.
Adjusting the Vent Valve
Set the throttle linkage to the hot idle position. The groove in the vent valve rod should now be even with the open end of the vent valve rod retainer. Bend the arm on the vent valve rod actuating lever where it contacts the accelerating pump lever to align the groove with the edge of the bore.
To replace this rod:
- If the vent hole is plugged remove it by tapping around the edge with a chisel. Assuming it has an aluminum plug. Anything else plugging the hole will have to be drilled. Drill the hold slightly bigger than the rod lip.
- Remove the old rod at the clip.
- Install the new spring.
- Push the rod into the hole and secure by placing the clip over the lever, then push the rod through the hole.
- To adjust:
- Open choke valve to full open.
- Close throttle all the way closed.
- The rod lip should be at the edge of the hole, or slightly inside.
- Adjust by bending the end of the lever.
I purchased the rebuild kit and new vent valve rod to boot (original plastic one was broken) and the vent rod has no markings or grove to set in correct position after I have adjusted for high altitude.
Could you please let me know the distance from the stop for the spring to where the notch should be? Judging from the plastic one it’s roughly 1/2″ does this sound correct?
Adjust until the round disk is near the edge of the hole. Just make sure it doesn’t come out.