Leak: fuel pooling on the intake manifold

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trebor75

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Take a look at the picture. After a good day of driving today I found fuel where the arrows are pointing (I had wiped most of it away before taking the picture). While idling I could also see some, what I believe is fuel, bubbling/sizzling between the intake and head (closest to the area of the top arrow). Passenger side was the same, also pooling and sizzling. I have before this also noticed a hissing sound that I cant recall hearing before. Mostly while cruising. It's not very loud, but it's there. The carb is as good as new, bough it recently new.

The hissing sound would suggest a vacuum leak. I have gone over the carb and plugged everything. It was still there.

The intake manifold was removed last sumer when I swapped cam. I have gone over it and torqued it to the right specs. What may cause the pooling? Bad intake gaskets? Blown head gasket? Cracked intake or head? Need your knowledge!

This is the combo:
1970 duster
1965 - 273 commando
Cam: Comp Cams Magnum 282S - 282/282 Lift 495/495 (solid) Beehive Springs
Edelbrock D4B intake / Holley 670 Street Avenger
Pertronix Ignitor II & Flame Thrower coil
Hooker Headers
2.5" Dual Exhaust / Super 44 Flowmaster
8 3/4 - 3.55 - SureGrip
727 auto / Shift Kit
10" 2000 stall converter
B&M Quicksilver Shifter
 

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Check the float level first
I checked it with the engine turned of just after idling. It was perfect, just at the bottom of the threads. But this should be done with the engine idling right?
 
Checked float level yesterday and that is not the problem.
 
Are you sure its fuel and not oil. If you didn't apply sealant to those intake bolts oil will climb their threads and pond there.
If it is fuel it could be coming from the supply line fittings.
 
I was thinking exactly what RedFish said. We pulled the intake on my 340 years ago and didn't put sealant on the manifold bolts. My engine always had a puddle in those nooks and crannies.
 
Same here on the intake bolts. I never fixed it, but found out later what was causing it. I chased the carb also, and it wasnt fuel causing it the whole time. There was never a puddle, just a stain with some crud in it. I guess the oil was baking off or something.
 
As the others have said, pull the intake bolts....one at a time...and reseal them. If you still have issues after that, we can work on it some more.
 
Thanks for all the help. I will go over it again and check the bolts.
 
Try sticking your finger in the puddle and smelling it to see what it is.


(Smell my fingers.... LOL!)
 
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