Throttle shaft leak after shut down
 

I have a DC 94 carb on my 40 Ford 85 hp V8, it is about 5 years old. I am running 2lb fuel pressure. Lately, it has been leaking fuel from both ends of the throttle shaft after the engine is turned off. After the last time it occurred, I let the car sit for a couple days and then removed the top of the carb. The fuel bowl had about 1/2" of gas in it. I checked the inlet valve, and float adjustment, and both seemed good. I removed the rest of the carb from the manifold, removed the base of the carb and all looked clean and in order including the power valve. The throttle shaft has perhaps a couple thousandths play to the bore. Put Humpty Dumpty back together again and still have the same issue. Where do I go from here??

Sorry for the long read
Steve

Re: Throttle shaft leak after shut down
 

Charlie Schwindler, CharlieNY here on the barn.


5845 Cole Rd
Orchard Park NY 14127


[email protected]



He'll put it through his "carburetor spa" and have it as good as new!!!

Re: Throttle shaft leak after shut down
 

1044,
This issue is usually a loose throttle shaft. The loose shaft some how upsets
the vacuum and some fuel is siphoned out of the bowl up into the nozzle bars and
deposits itself on the throttle plates then out the shaft. I have found the only way to
check the fit between the shaft and base is a complete disassembly. Bore in base is usually out of round and the shaft egg shaped. 75% of the 94's I build leave my shop with an oversize shaft.
Charlie ny

Re: Throttle shaft leak after shut down
 

My carb that Charlie did for me was perfect. But, at times on a hot 85+ day, when I shut it [8BA] down, I would get trace amounts of fuel on the shaft ends. This poor excuse for gasoline percolates so easy & runs everywhere leaving the bowl half empty. Also majes for harder starting.

Re: Throttle shaft leak after shut down
 

I would be interested to know if there is a difference between a new carb or a repoped carb, with this condition ,

Re: Throttle shaft leak after shut down
 

I’m lucky I have a gas station within walking distance that sells non ethanol fuel, it cost more but it works better in my flathead.

Re: Throttle shaft leak after shut down
 

repop and vintage originals suffer the same.
Charlie ny

Re: Throttle shaft leak after shut down
 

Non-ethanol should help. You can also try EAB ‘high-rise’ style nozzle bars

Re: Throttle shaft leak after shut down
 

Thanks to all for the helpful info!!
Steve