Vikki - the problem (if one exists) with the internal dashpot is wear in the dashpot cylinder. The vertical movement of the dashpot tends to wear the cylinder in the carburetor housing, thus allowing the dashpot piston to move sideways, and eventually bind.

The umbrella style fuel valve does not have a clip.

Amervo - with no disrepect intended, removal of the clip from the fuel valve is not a good idea. The placement of the clips is quite confusing. Some are designed to be placed behind the bar on the float arm, some in front of the bar on the float arm, but I am unaware of any which are to be placed in either of the 2 slots in the float arm which one would think is the proper spot! With the carburetor on the bench, install the fuel valve with the clip; and then with a string looped under the toe of the float, move the float from fully opened to fully closed observing the action of the valve. If the valve binds, place it on the other side of the bar, and repeat the test.

Removing the clip from a passenger vehicle driven daily will probably not be a problem. However removing the clip from a non-passenger vehicle or a passenger vehicle which is not driven daily may result in the valve sticking in the seat, thus preventing fuel from entering the carburetor.

Al - while I disagree with Amervo's diagnosis that the accelerator pump is the problem (based on the fact you are also having problems at 50 MPH when the accelerator pump should not need to be functional); the test that Amervo suggested should always be done when having this type of problem, as it positively will prove either the accelerator pump is good or bad. And Amervo may be correct. Neopreme accelerator pumps fail more frequently on vehicles which are infrequently driven; as the neopreme, having one been in gasoline, tends to turn hard if removed from gasoline. Todays very volatile fuel will evaporate from the bowl, thus allowing the accelerator pump to turn hard, and fail. When replacing an accelerator pump, use a leather pump if possible.

I especially agree with Amervo's comment about the mechanic. It is much easier to say "parts are not available" than to say "I don't know how to work on this item". You can always determine what the mechanic meant by asking if he will do the work if YOU supply the parts.

Jon.