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car is running rich how do you lean out a Holley?

  • Thread starter Thread starter 65stang289
  • Start date Start date Dec 9, 2003
6

65stang289

New Member
Mar 5, 2003
922
0
0
Fort walton Beach FL.
Dec 9, 2003
#1
  • Dec 9, 2003
  • #1
I need help on how to lean my Holley 600 out. I know it is the two screws on the side but dont know what way to turn them.
 

68GEETEE

5 Year Member
Nov 21, 2003
481
5
38
Texas, USA
Dec 9, 2003
#2
  • Dec 9, 2003
  • #2
as far as the screws, with the engine off turn both screws clockwise until they are all the way in. Pay attention to their position and back them out two full turns. You must do both screws equal number of turns. Start the engine. From this point you can lean it by clockwise turns, or rich by counterclockwise. Again it is vital that both screws have the same number of turns. Keep in mind there are other factors that could make her run rich. Vacuum leaks come to mind.
 
6

65stang289

New Member
Mar 5, 2003
922
0
0
Fort walton Beach FL.
Dec 9, 2003
#3
  • Dec 9, 2003
  • #3
My screws show about ten threads on each side they are out alot so I have to turn them both in all the way and then 2 full turns out and just keep turning it out till it runs ok.
 

pabear89

Active Member
Apr 15, 2003
2,126
0
46
High in the Hills of So Ca with the Voices in My H
Dec 9, 2003
#4
  • Dec 9, 2003
  • #4
65stang289 said:
My screws show about ten threads on each side they are out alot so I have to turn them both in all the way and then 2 full turns out and just keep turning it out till it runs ok.
Click to expand...


Or in, I use a baseline of 1 1/2 turns out from fully closed on the mixture screws.
A 1 turn after screw touches the throttle plate to start with.
Adjust throttle screw till it reaches about 6-700 rpms and work the mixture screws till a smooth idle.

PB
 
D

D.Hearne

New Member
Sep 29, 2000
11,730
6
0
south louisiana
Dec 9, 2003
#5
  • Dec 9, 2003
  • #5
pabear89 said:
Or in, I use a baseline of 1 1/2 turns out from fully closed on the mixture screws.
A 1 turn after screw touches the throttle plate to start with.
Adjust throttle screw till it reaches about 6-700 rpms and work the mixture screws till a smooth idle.

PB
Click to expand...
The two screws y'all are trying to adjust are the IDLE mixture screws. They have no effect on the mixture once you hit the gas pedal. To change this, you have to re-jet the carb. The jets are located inside the main fuel bowl.
 

RaSMG

Founding Member
Oct 5, 2002
270
0
0
Central Cali
Dec 10, 2003
#6
  • Dec 10, 2003
  • #6
read what d hearne said .. the screws on the side of the metering blocks are the idle adjustment screws which only effect the idle mixture .. you want to get them adjsuted to put out maximum vacuum at a given idle rpm or to maintain the highest rpm once warmed up .. that means they are adjusted properly, then adjust the idle speed to speed or slow it down. shouldnt take more than 2 full turns out on each side, usually between one and one and a half turns on a holley/demon. if its leaning out on the top end(read the plugs) then you need larger secondary jets, if its leaning out between 1000-3000 rpm under partial throttle then its the main jets .. also try different timing curves most people with carb problems just have mistuned ignitions .. and try different vacuum advance springs if the secondaries are vacuum operated.
 
D

D.Hearne

New Member
Sep 29, 2000
11,730
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0
south louisiana
Dec 10, 2003
#7
  • Dec 10, 2003
  • #7
Chances are the Holley 600 he has , will have a secondary metering plate, and not jet screws in a block.
 
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