As I'm sure you realize, there are so many possible causes that it would
only be a wild chance that one could diagnose it for you without seeing the
car. If you have access to someone with an engine analyzer, they could
track it down for you immediately. Failing that, you will have to try
different things until you hit on the right cause.
Since you have a Holley carburetor, that is indeed always a suspect in poor
idle situations. If you have access to another carburetor, you could try
just swapping it temporarily (it only takes about 15 minutes to swap a
carburetor), that would nail down whether or not the dreaded Holley is the
culprit. If you smell gas around the engine, it is almost surely at least
part of the problem. The usual failure for these is internal leakage, which
you cannot see but you can hear, if you remove the air cleaner and listen
for a dribbling sound from the air horn area.
Rebuilt carburetors are often the source of trouble - the best success has
come from replacing these with new AFBs, which are readily available for
less than $300.
However, your problem might have nothing at all to do with the carburetor -
you really should have it diagnosed by a professional before you start
throwing money at it.
Dick Benjamin
----- Original Message -----
From: Sykes Robert P. <bobsykes@xxxxxxxxxxxxx>
To: <mailing-list@xxxxxxxxxxxxxxxx>
Sent: Wednesday, September 18, 2002 6:29 PM
Subject: IML: galloping 440
>
> I have a 68 Crown with the 440 and Holley carb. The carb
> was supposedly professionally rebuilt by the previous owner before I
purchased
> the car 6 months ago, and he provided receipts to verify this. The fuel
> pump was also replaced. The car has been hard to start from the day I
> received it, and now has developed a "gallop" or surging at slow idle.
> When the car sits idling after the engine is hot, it sounds like it has a
racing
> cam in it. Any suggestions on where to start to correct the problem?
> Thanks for any ideas you have.
>
>
>
> Bob
>
>
>
> --- Sykes Robert P.
>
> --- bobsykes@xxxxxxxxxxxxx
>
> --- EarthLink: It's your Internet.
>
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