Flooding at idle

[1985 CCX]

Guys

My car 1985 carburtated car
The car has 8400 miles and all stock
As I start the car and let it idle it will rapidly start to flood
What happens as a trickle effect happens allowing fuel to start dumping into the carburetor
I have rebuilt the carburetor changed all the gaskets checked visually all emissions lines
Could this be a simple omissions fix possibly pulling a vacuum from somewhere,  broken emissions valve.
Anyone else experienced this

[westcott]

Is it the standard Holley 4180C ?

A view main root couses for flooding I would check even if the carb is reworked (assuming car is on horicontal base) :
- wrong adjustment of fuel level, too high
- too high fuel pressure, normal for a standard Holley is 6 PSI, flooding will start somewhere between 7 and 7.5 PSI depending on the needle valve condition
- not working or leaking fuel needle valve /seat
- fuel tank under pressure

- open the fuel filler and check again for flooding. If it is still flooding with an open fuel filler cap, the tank evacuation via the charcoal filters or the valve on top of the tank is not the problem, If not check the items.
- check fuel pressure and return line
- check fuel level adjustment and needle valve / seats for correct setup and shut off function. I allways replace needle valves with a carb rebuild

The 4180 normally has sealed allen head idle adjustments in the base plate and completely different primery metering block then the 4160 / 50 or 1850. So please don't put metering block service parts from 41xx or 1850 in the 4180 primary metring block side. Secondary metering blocks need small mods too if used from different carbs. Main metering jets are interchangeable

Double check the service parts used.

Next would be disable the EGR base plate function to see if the EGR circuit is causing problems.

[1985 CCX]

Thanks for the advise and council

The car is completely stock, 1985.  It only recently started having issues at idle and I noticed the fuel would trickle in and cause fluttering then die as it floods.
I adjusted the floats to no avail, thought the carb may be ready for an overhaul.  Took it to a carb shop, complete check up new valve and new gaskets and rubber. 

Reinstalled all new NOS gaskets, tubing etc...  Still does it almost immediately upon start and note it has been getting worse over last couple hundred miles.
Thinking it may be related to emissions?  There are two solenoid valves in the car that I have read need to work in unison. 
One purges the canister and the other to allow open fumes to flow into carb?
I will try EGR but is looks new and moves by the touch of a finger.  Ill keep all poste don my success...
Ill open fuel cap to ensuring no PSI

[1985 CCX]

https://lmr.com/item/LRS-9915A/1984-98-Canister-Purge-Valve-46-50L

This may be the culprit?

[westcott]

I still think that the needle and seat or the o-ring on the assembly is causing the problem. Fuel is passing by somehow. I would remove the needle and seat assembly by removing the adjustment nut and turn it out until it can be liftet out. Then replace the o-ring and check the valve assembly. Put it back in,  adjust the fuel level to just below the level holes and try again.

[1985 CCX]

I'll give it a wirl

[1985 CCX]

After going through the emissions and resetting the carb all is well.  Just thought I'd bring finality to the thread.

So far, smooth operation!  ;D