I have a quadrature with a electric choke on my stock 84 Chevy truck with a 350 engine. The carb and choke has been working fine all year but now that its got a little colder it stumbles after start up. When it first did it I opened hood to see fuel coming out of fuel pump body. I replaced the fuel pump and it still stumbles but does not push fuel from pump body. I dont know if thats a separate issue but the pump is new with a regulator set at 3.5-4psi.
On a cold morning(every morning) I press the pedal down once and turn the key. The engine starts up perfectly. After about 5-10 seconds it starts to stumble and smell rich. Then after about another minute or two it clears up and is running very smooth again. When it start to stumble I press the pedal and the stumble does not clear up but RPMs do raise. After a minute it will clear up also.
Any ideas ? I dread messing with the choke because its seems a small adjustment makes big changes.