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Old 10-24-2018, 11:24 AM   #1
Bobbed72
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Quick fuel carb leak?

Have Brawler carb that is a rebranded quick fuel. I recently swapped out idle feed restrictions on both meter plates and now it runs rough for a minute with 8:1 AFR. Also noted after it sits awhile the fuel in the bowls goes down. Almost below the sight glass after a few days. I pulled the carb and set it on my work bench with the bowls full but I didn't observe any leaks. I'm stumped.
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Old 10-24-2018, 05:19 PM   #2
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Re: Quick fuel carb leak?

Looks like I didn't give good information. The restrictor swap was to lean out the idle mixture. My mixture screws were less than half a turn out. So I don't think it's them causing the overly rich idle. Could I have a leak in the meter plate gasket that would drain the bowls into manifold?
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Old 10-25-2018, 07:50 PM   #3
PGSigns
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Re: Quick fuel carb leak?

On the motor the heat will evaporate the fuel out the bowls. While it is running you need to set the floats and look at the boosters and see if you have fuel pulling over. then you need to look at the power valve.
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Old 11-07-2018, 12:44 PM   #4
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Re: Quick fuel carb leak?

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Originally Posted by PGSigns View Post
On the motor the heat will evaporate the fuel out the bowls. While it is running you need to set the floats and look at the boosters and see if you have fuel pulling over. then you need to look at the power valve.
Jimmy
I was thinking evaporation but I don't know how much to expect. Floats are good. Power valve looked ok when I pulled the meter block. No fuel behind it.

Idle is driving me nuts. Sometimes in gear it's around 12 other times it's 14 with no changes made. Still haven't figured out the 30sec rough idle that is overly rich at 10.

Last edited by Bobbed72; 11-07-2018 at 01:23 PM.
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Old 11-07-2018, 03:32 PM   #5
geezer#99
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Re: Quick fuel carb leak?

What’s your idle rpm?
What’s your initial timing?

Is this a 4 corner idle carb?
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Old 11-07-2018, 08:05 PM   #6
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Re: Quick fuel carb leak?

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Originally Posted by geezer#99 View Post
What’s your idle rpm?
What’s your initial timing?

Is this a 4 corner idle carb?

Idle no load 800
idle with load 650
Initial timing 18 degrees at 600 rpm. MSD box controls ignition no distributor.
yes, 4 corner adjustment.
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Old 11-08-2018, 09:28 AM   #7
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Re: Quick fuel carb leak?

Timing and idle look good.
Is this a recent Msd install?
Msd isn’t what it used to be. Quality has gone in the crapper.

I’ve read about lots of problems with those carbs. Mostly posts on Hotrodders forum. Common symptoms to what you’re seeing.
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Old 11-08-2018, 11:47 AM   #8
Bobbed72
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Re: Quick fuel carb leak?

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Originally Posted by geezer#99 View Post
Timing and idle look good.
Is this a recent Msd install?
Msd isn’t what it used to be. Quality has gone in the crapper.

I’ve read about lots of problems with those carbs. Mostly posts on Hotrodders forum. Common symptoms to what you’re seeing.
The MSD has been on since the motor rebuild. I have the 6014 and most of the feedback I've found centers around the 6010.

The current issues are new. Popped up after the IFR change. There does seem to be inconsistency with this carb. But i'm new to carb tuning especially with a AFR gauge so i'm not sure what's normal and what's not in relation to variation in AFR readings when no changes have been made.
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Old 11-08-2018, 12:23 PM   #9
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Re: Quick fuel carb leak?

If it’s possible I guess you need to go back stock with the original set up.
I’ve also read that 1/2 to 1 turn on the mix screws is normal on those 4 corner idle carbs.
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Old 11-11-2018, 12:03 AM   #10
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Re: Quick fuel carb leak?

Quote:
Originally Posted by geezer#99 View Post
If it’s possible I guess you need to go back stock with the original set up.
I’ve also read that 1/2 to 1 turn on the mix screws is normal on those 4 corner idle carbs.
Thinking your right about going back to stock. Boogered one of the IFR's when removing. I'll have to buy new ones. I changed them cause I was having to go less then 1/2 turn to lean out the mixture.
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Old 11-15-2018, 08:09 PM   #11
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Re: Quick fuel carb leak?

Went back to the original settings. Weird idle issue seems to be resolved. Now to understand why I lean out to 14-15:1 between 1 and 2k rpm with part throttle cruise.
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Old 11-16-2018, 04:32 AM   #12
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Re: Quick fuel carb leak?

Subbed for info.
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