newbie2vette

When I got my car it came with Holley Dual pump carb and had a spacer between the manifold to the carb. It was leaking at one of the pump area so I got a new Edelbrock 650 CFM not sure which series it is.

In order for the air cleaner that came with the new card I had to remove the spacer. what added value having the spacer installed with the old Holley. do I need it with the new carb? Recently after driving the car for anything longer than 10 minutes, park it for 10 minutes or so it is hard to start acting like it is flooded. it takes several cracking before it decides to fire up, when it does I have to assist it with the throttle. After several reving it up, as if I just cleared and extra fuel it will idle. Also, when I get into the garage I can smell fuel. At first start in the morning or after is sat overnight, just two pump on the throttle is will fire up and will idle.

Is the old holley it came with worth re-building? I sure hate to think this new carb is not working as advertise. what can I check to verify it is actual dumping fuel after I shut the engine down?

MelWff

since you dont mention the list# of the Holley, does it have external sight plugs in the fuel bowls to assist in adjusting the float levels? If so check the levels, sounds like they are high. You do realize a 72 LT1 came from the factory with a 780 CFM carb?

7t9l82

it wont run as well with that Carb on an lt-1. someone worked on that motor a Carb spacer is a tuning trick to increase Plenum volume my advice is rebuild the original Carb and use it.

trainor

When I went from my stock rochester to my edelbrock 650 it did the same thing. Starts great cold but blubbers and starts bad after shut off, while still warm. I called edelbrock and they said it was heat soaking, I bought the wooden spacer and put it on. My problem was gone and is still gone. Say what you want guys, but a pretty easy fix for $21.00

Phil Zell

on a small block a lot of double pump Holley's will not function without a spacer, the secondary pump will hit the manifold

rvazquez

newbie2vette, I understand the Eldebrock is a very good carb and may just need to be adjusted or tweaked a little more to get it to run properly, as the above poster stated the original 72 LT-1 Holley was a 780 cfm carb and you replaced it with a 650, so it might be a little on the small side.The list #6239A or #6239-1 and part no#3999263 should be stamped on the front of the air horn. the third line of the stamping is the date code.If your Holley is the original carb, I would definitely consider having it professionally rebuilt and put back on the car with the correct 1/4" spacer installed
A simple adjustment of the float bowls may be all it takes to remedy the flooding issue and you may want to tap the outside of the carb float bowl covers to see if it unsticks the bowls. just remove the covers and spray some gumout all over and see what happens. Let us know what you decide to do.
Regards
Roy