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Holly carb surging #3053513
06/26/22 01:51 PM
06/26/22 01:51 PM
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fredericksburg,va
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cudaman1969 Offline OP
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fredericksburg,va
Not sure why but think it might be a leaking needle seat. Sat for a year and had to tighten up the acc pump and replace manifold gasket. Now this, any other ideas?

Re: Holly carb surging [Re: cudaman1969] #3053591
06/26/22 05:39 PM
06/26/22 05:39 PM
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Rittman Ohio
fourgearsavoy Offline
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Rittman Ohio
How is your float level ? If your needle and seat were leaking or sticking the float level would be too high . Pull the sight plug and check it. Sometimes a power valve will cause this.

Gus beer


64 Plymouth Savoy
493 Indy EZ's by Nick at Compu-Flow
5-Speed Richmond faceplate Liberty box
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Re: Holly carb surging [Re: fourgearsavoy] #3053634
06/26/22 08:44 PM
06/26/22 08:44 PM
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fredericksburg,va
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cudaman1969 Offline OP
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Checked while running and no fuel leaking down Ventura’s, only does it after complete warm up. I have another carb I’ll stick on to try this week sometime, have to use van tomorrow. One other thing, if I hold pedal down a little more in gear at a stop light it evens out. Maybe trash in idle circuit.?

Last edited by cudaman1969; 06/26/22 08:47 PM.
Re: Holly carb surging [Re: cudaman1969] #3053640
06/26/22 09:11 PM
06/26/22 09:11 PM
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Long Island, New York
57Fury440 Offline
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Is it possible it's a gas problem? Maybe the carb is too hot, and the gas is boiling.

Re: Holly carb surging [Re: 57Fury440] #3053680
06/26/22 10:54 PM
06/26/22 10:54 PM
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Chicago
PurpleBeeper Offline
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Chicago
I'm going with year old gas


70 Roadrunner convt. street car 440+6, NOS, 4-spd, SS springs '96 Mustang GT convt. street car '04 4.6 SOHC, NOS, auto, lowered "Officer, that button is for short on-ramps"
Re: Holly carb surging [Re: PurpleBeeper] #3053710
06/27/22 07:15 AM
06/27/22 07:15 AM
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Someplace you aren't
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SomeCarGuy Offline
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Mine is doing this. Only after hot or heat soaked. Perfect otherwise. Thinking I might’ve gotten a load of winter gas. Picked up some race gas to blend in last week. Vapor pressure of the race stuff is 6 psi. Winter blend can be as high as 14 psi I was told. Yikes!


I want my fair share
Re: Holly carb surging [Re: SomeCarGuy] #3053726
06/27/22 08:11 AM
06/27/22 08:11 AM
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fredericksburg,va
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cudaman1969 Offline OP
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Almost empty filled it up same, did same after fill up 2 months ago

Re: Holly carb surging [Re: cudaman1969] #3053760
06/27/22 10:17 AM
06/27/22 10:17 AM
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Colleyville
3hundred Offline
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Colleyville
Originally Posted by cudaman1969
Almost empty filled it up same, did same after fill up 2 months ago


Surging at idle, cruise?


'68 Fury Convertible
'69 300 Convertible
'15 Durango 5.7 Hemi
'16 300 S Hemi
Re: Holly carb surging [Re: cudaman1969] #3053911
06/27/22 06:06 PM
06/27/22 06:06 PM
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Rochester, New York
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GregY Offline
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I am just going to toss something out there, because your symptoms sound a little like what mine were.

I had a nearly brand new fuel filter on (mech fuel pump, 3/8 barb metal-housing filter), so I didn't think that was my problem. But for kicks, I took it off and I discovered that all I had left was the outer housing and a metal inner part, all of the paper filter part was gone, and the residue or whatever presumably in my carb. I didn't find any big pieces. I am pretty sure the filter was not like that when I put it on, or I would have heard it rattling.

Anyway, I disassembled the carb, blew out all the passages the best I could with carb cleaner and compressed air, and it seems to be fine now.

Greg




Last edited by GregY; 06/27/22 06:08 PM.
Re: Holly carb surging [Re: GregY] #3053935
06/27/22 07:37 PM
06/27/22 07:37 PM
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fredericksburg,va
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cudaman1969 Offline OP
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The Original filter that screws into bowl (1987) I’ll check it out. I surges at idle about 600, if I raise a little in gear it kinda evens out. Better today from short drive. Could very well be trash in there

Re: Holly carb surging [Re: cudaman1969] #3053962
06/27/22 09:22 PM
06/27/22 09:22 PM
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Omaha Ne
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TJP Offline
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Originally Posted by cudaman1969
The Original filter that screws into bowl (1987) I’ll check it out. I surges at idle about 600, if I raise a little in gear it kinda evens out. Better today from short drive. Could very well be trash in there


have you checked for vacuum leaks or tried adjusting the idle mixture ?

Re: Holly carb surging [Re: TJP] #3053969
06/27/22 09:37 PM
06/27/22 09:37 PM
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fredericksburg,va
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cudaman1969 Offline OP
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I will this weekend when I have more time, busy doing the Dentist office this week (big project)







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