My car has been working great all summer, however yesterday I went to gas up and on my way home it started sputtering and quiting at complete stops.
Checked it out today and it seems that the car will idle then fuel bubbles up out of the carb and it bogs out and quits. Also you used to be able to just flick the key with no/minor pump and away you went, now you need to pump it and hold it down to get it to start. When it does start is sputters and smokes until you get it reved up and let it idle at a high RPM.
Is there a float stuck? or does it sound like a new carb is needed?
If the fuel is bubbling up and out of the carburetor, it should be safe to assume the choke is opening properly, but I felt I should at least suggest that as a possible cause for it running extremely rich. Sometimes, if you tap somewhat aggresively on the carburetor with the butt end of a scewdriver, it will allow the float to go back to a 'relaxed' position. That may be good for the short term, but if the float is STICKING like that you should probably take off the top and see why. Another possible is if a piece of dirt gets stuck between the needle and seat of the carb. In those cases, it may be practical to take the fuel inlet fitting loose and apply very light air pressure. In either instance, be careful to NOT over-do it.
I disconnected and plugged the fuel line. Then ran the carb dry. Then blew some air through the fuel inlet on the carb. Good as new!!...until it happened again about 2 months later. I wound up rebuilding the carb a couple months ago(replaced the float, too). So far, so good.
Float wasn't stuck but the little wire thing that keeps the float attached to the needle was missing. Luck for me the old man had kept the old carb he took off it in the 80's and it had the same float setup.
I put the float from the old setup in and blew it all out.
The reason that the hair clip was missing is that they can cause the needdle not to seat. I had an ongoing problem until I canned the clip. See how it goes.
Well so much for running fine....I took it out again today and now it appears that fuel is leaking out of some kind of plug in the passenger side of the carb! It bogged out as I was taking off from a stop sign and wouldn't start so I took the breather off and she was oozing fuel out that plug on the base of the carb. I waited until it had drained out and eventually it started.
Does this new development mean a new carb? Or perhaps a rebuild?
Hmmm. It seems that the one problem has morphed into two. The gas doesn't usually come out there when the float sticks. I think you may have an internal gasket failure. Whether it matters or not when you get it to quit flooding is the question. You may need to make a float level adjustment now. Before you go any further make sure you have a large canister filter in front of the carb. This problem could stem from dirt/contamination in the fuel. I would also get some STP carb cleaner and clean the needle and the sleeve it rides in. 2 bbl Rochesters are bullitproof with a good filter. After lots of service they build up fuel varnish on the needle.
If the float is one of the polynitrophyll closed cellular foam (whew!) units, it may be heavy; as they occasionally absorb fuel.
There may be "gum" or "varnish" (modern fuel residue) on either the fuel valve plunger or the float arm, causing either to stick.
The fuel tank vent may be clogged; and in hot weather, the expansion of the fuel when heated may cause pressure on the tank, thus overdriving the fuel valve/float combination.
Other possibilities exist.
As to the float valve clip: the little hole(s) in the float arm that appear to be where to clip the clip should NEVER be used for that purpose on Rochester carbs!!! On various models, the clip should be installed over the front edge, or much more likely over the back edge of the float arm. After installing the fuel valve, float and clip, and setting the float drop; ALWAYS orient the casting in the normal configuration (on a two-barrel turn the airhorn right side up) and gently work the float from full open to full closed a few times to check for plunger bind. If the clip is properly installed, the plunger will not bind.
Jon.
Good carburetion is fuelish hot air Owner, The Carburetor Shop LLC