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Old 09-24-2020, 10:11 AM   #1
phlegm
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QJet running fat

Hi guys, my DD project is getting down to little punch list stuff

fixing a tiny rear diff leak this weekend, but while I am at it I want to tune the carb a little. It runs high idle at cold idle, I corrected that this morning taking it down to about 1k RPMs from1300. but it still runs very fat, a lot of gas smell and the front of the carb is gooey. I had the carb rebuilt last year and have done the tricks with leaning it out and then bringing it back a quarter etc... I even opened it up once and sprayed it out thinking the needle wasnt seating correctly.

Any tips? It runs good sounds good but I would like to quit wasting gas and smelling it
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Old 09-24-2020, 10:36 AM   #2
68Gold/white
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Re: QJet running fat

Posting your carb number will help. All Quadrajets are not ALL the same...tuning wise
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Old 09-24-2020, 10:41 AM   #3
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Re: QJet running fat

Quote:
Originally Posted by 68Gold/white View Post
Posting your carb number will help. All Quadrajets are not ALL the same...tuning wise
Thanks! I will
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Old 09-24-2020, 10:46 AM   #4
Richard2112
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Re: QJet running fat

I'm still running the Q-jet I overhauled a few years ago. It was doing the same thing, running rich and seeping fuel. I put new floats in at the time and re-adjusted the level. Thought I would have to rejet but it's run well since the overhaul. It's sorta difficult to tell but the floats can become saturated over time and won't work exactly as intended.

However as has been stated, not all Q-jets are the same. A number helps.
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Old 09-24-2020, 11:27 AM   #5
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Re: QJet running fat

Take some pictures, also...top. front, especially. If you had the top off, was the float brass or plastic (black in color)?
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Old 09-24-2020, 11:48 AM   #6
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Re: QJet running fat

Quote:
Originally Posted by 68Gold/white View Post
Posting your carb number will help. All Quadrajets are not ALL the same...tuning wise
7041211 IT
0691 ---. can't see all this one
Attached Images
  
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Old 09-24-2020, 05:21 PM   #7
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Re: QJet running fat

7041211 Shows up as '71 350 CI engine. The other info is build date, and then probably the rebuilder's own code. You can weigh the float. The composition float weighs 8 grams if it isn't saturated with fuel.
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Old 09-24-2020, 05:53 PM   #8
phlegm
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Re: QJet running fat

Quote:
Originally Posted by Steeveedee View Post
7041211 Shows up as '71 350 CI engine. The other info is build date, and then probably the rebuilder's own code. You can weigh the float. The composition float weighs 8 grams if it isn't saturated with fuel.
I will have to find some scales, I havent had a set that measured grams since college

that may be it, maybe he put the wrong float in? not sure.

Anything else to check while I am in there? Of course, go ahead and spray it out, cause why not...
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2010 Acura TL
98 Mastercraft "FrankenStar" 225
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Old 09-24-2020, 07:54 PM   #9
geezer#99
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Re: QJet running fat

I wouldn’t open it yet!
Clean it off and then definetly see where the leak is.
Looks like the base plate gasket might be the culprit. Evidence of that is the soot trail from the vac hose connection and by the fuel inlet. No evidence of flooding though. That usually shows up on the ends of the throttle shaft and leaves a dark stain on the intake walls.
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Old 09-24-2020, 08:18 PM   #10
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Re: QJet running fat

I was going to ask but forgot. What is that guck at the air horn/float bowl gasket area?
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Old 09-25-2020, 05:14 PM   #11
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Re: QJet running fat

I'd pull it and see if the bottom of the jets are leaking. I have had to JB weld the bottom of all the jets on my quads. two front ones you can see without removing the base. the back two you'll have to remove the base. This a common issue and should be looked at first in my opinion.
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