Hard Start Cold

My Vette (76 - L48, 4spd, Stock, Qjet) always needs about 10-12 pumps of the pedal to get started, after sitting more than a day or two.

Is this just the nature of the beast or is a carb rebuild in it's future? Once started, it runs great, choke works as normal and then will idle smooth, etc. Warm starts are not a problem.

We seem to be getting closer to the "off season" every day and was thinking "might as well" add this to the list.

Thanks

Sounds like a common Q-Jet problem. There are lead plugs at the bottom of the fuel bowl, they have a tendency of leaking while sitting for a day or so. If you are going to rebuild your Q-jet, use a 2 part epoxy and coat the lead plugs. This helps with the leak down problem.

Plus it seems that your accelerator pump may be a little worn since you have to pump the heck out of it.

Before you go rebuilding you carb, check the primary (front) throttle shaft for excessive play. Grasp the throttle linkage and try to move it front to back/ up and down. If there is slop in there, the throttle shaft is worn, this will cause a vacuum leak which is common to Q-Jets. This problem requires some drilling and bushings installed to make a rebuild work properly. There are kits available for that problem.

Let us know what you find

Sarge

Thanks Sarge and Ken for your responses. I have a carb book by Doug Roe and saw a picture of the plugs you are referring to.

Does that fuel leak into the throtle body or out through the gasket? I have never seen what appears to be a leak around the gasket.

I'm still trying to figure out how a carb is supposed to work. With Doug Roe's book, and the the write up that Ken did - I seem to comprehend a bit more each time I go through it, but those first two or three attempts were very discouraging to say the least. 

I still plan to rebuild it myself, but I need to get my confidence level up just a bit more. 

Thanks again -

Yes, I've tried just about everything I can regarding the hard starting of my '76, including the 'well plugs'.

I've decided it is the loss of the anti-evaporation additive in modern fuels that is causing it. 

Oh well, just keep cranking.

New fuel pump in recent history?

Alas yes, last year, didn't make any difference.

It's not blended "for fuel injected" cars.  It's blended for the EPA and their stupid regs.

My Holley carb doesn't have this problem. Starts right up after sitting for a month.