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Jeffblitz69

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Reply with quote  #1 
The invoice number is 47798, all of a sudden my car started running lean, can hear it missfire and hard restarting after it sits. I have 7 lbs of pressure at carb, is there anything I can check for this.
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Reply with quote  #2 
I would tear it down and inspect it for foreign material in it.  Most likely in the needle and seat.
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Jeffblitz69

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Reply with quote  #3 
Would you happen to know the bowl and metering block gasket number I need for holley. I have your numbers on gaskets. I did not rip them taking apart are your reusable or not?
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Reply with quote  #4 
If you are not using our gaskets, this is a real good value in gaskets for your carb.

https://www.jegs.com/i/Quick-Fuel/793/8-2000QFT/10002/-1

Use motor oil on the face of them and the main body when installing.



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Jeffblitz69

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Reply with quote  #5 
Thanks, if this Don't fix, ill send carb in for you to go through it.
Jeffblitz69

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Reply with quote  #6 
Thanks, I sent carb into you to have fixed, but I'm still having problems with it, rear bowl now holds fuel. But still having a problem when I put in gear drops about 350 rpm and real rough idle. Vac nice and steady in park at 10hg, put heavy springs in dist no change.
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Reply with quote  #7 

1. Remove the rear metering block (and set it 5 feet away from you).  

2. Then look down on the main body in the rear and you will see two brass screw in restrictors.  

3. Use a 1/16th allen wrench and unscrew them and put them in your pocket.  

4. Then re assemble your carb and fire it up.  

Then once again adjust the idle mixture screws, turn the idle mixture screws in until the engine hesitates on a quick jab of the throttle or tries to stall or lay over when put into get or under a light load. Then turn the mixture screws out until those issues go away. That is as lean as it will idle without having issues.

If after doing this however, you need it even richer yet, then simply install smaller air bleeds in the outer four corners (.063 is a good starting point to richen it up more at idle) if needed.  But do them in that order.  

Then once again adjust the idle mixture screws

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Jeffblitz69

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Reply with quote  #8 
There were no restrictor in carb, put back together I have it set at 1150 in park 900 in gear idles rough 4 coroners set at 1.5 turns out. Were it idles in gear best but still rough.invoice 52633
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Reply with quote  #9 
I should have thought ahead on this... remember it WAS OK.  Suddenly it started acting up.  

We should not have to make changes to the carb.  

We should look for reasons why it started acting up.  If youre sure it doesnt have anything plugged in it AND the ignition AND the engine is ok, try another carb and see if the issue continues.  If it doesn't its in the carb and more than likely something went bad... gasket or a power valve OR something is still plugged in it and it was missed during your tear down to find it.  Send it in to us and we can find it.

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Jeffblitz69

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Reply with quote  #10 
So took car to show about 40 mile drive. Still hard starting when cold. Have to fether gas for a few till it warms up, idle at 1200 in park 900 in gear and it jumps hard. Good power from stop or when rolling. Problem when at steady cruise hear popping out exhaust and bad when I let off gas. From under 3000 rpm, if crusing and I give it some gas it clears up. Only change to car is I added x pipe and moved mufflers back. Carb is set at 7.5 fuel pressure, timing is 24 initial all in 38 by 2800 rpm. Thanks for all you help so far I know we will get it solved.
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Reply with quote  #11 
If you're sure you dont have an exhaust leak, as a test, drop the front main jets 5 sizes and go for a drive and part throttle.   E back the effect on cruise. 

A richer idle OR a hotter plug will help it start and run better when cold.

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Jeffblitz69

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Reply with quote  #12 
Ok it did have a header gasket leak, all fixed. Still has a cruise speed misfire. I was running autolite 3924 changed to ngk 4901 that what it was set up with on dyno, that is a colder plug, misfire seemed to get worse with that plug. I put the 063 air bleeds in idles about 1150 in park 900 in gear lot better, real hard starting with those colder plugs. Idle screws out 1 turn. Getting better just need to clean up that off idle to cruise speed miss. It might of had that miss all along just could not hear it when mufflers were under my seat. Now with x pipe and mufflers way back I hear it.
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Reply with quote  #13 
What rpm (and about what blade angle - 5 or 15 degrees for example) is the misfire.  Trying to determine if its a main system rich or lean issue OR a Transfer system lean or rich issue.
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Jeffblitz69

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Reply with quote  #14 
I would say 5 but car hear it till I get above 3500rpm, if I'm at cruise say at 2500 popping a lot but as soon as I just give it just a little gas it start to clear up, when I put the original plugs in the colder plugs I had to turn idle screws up a lot to get it to idle, checked plugs real clean no carbon on ring, at all and porcelain white.
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Reply with quote  #15 
Im not sure if this is a carb issue or not... borrow another carb and see if it does the same thing.  You made moves that should have shown results or at least changes and we've seen no effect. 
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