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Author Topic:   carb help
Dirt Maniac

Total posts: 131
posted March 09, 2005 02:39 PM  
got a 600cfm holly with single metering plate and vacumm secondary-it's dumping so much gas in the inake that its fouling the plugs in a matter of seconds.changed metering plate and power valve,no change. even put the smallest jets ing the box in,no change. yall got any ideas?

Dirt Maniac

Total posts: 148
posted March 09, 2005 03:29 PM  
sounds like needle and seat either out of adjustment or not working.
on a holley you can remove the bowl and float assemnbly. Hold the bowl upside down, turn your compressor way down to under 10 psi, use a rubber tipped air nozzle to feed air into the carb inlet and adjust the needle and seat screw / nut so that it closes with the float level. that will be darn close to where you can start it up and make final adjustments. also a good way to identify a leaker.

Some People Race For A Living; I Live To Race

Dirt Maniac

Total posts: 131
posted March 09, 2005 08:18 PM  
we set the floats low and high-same thing. i even called the holley tech line. i'm thinking of trashing that carb and get a new one.

Dirt Freak

Total posts: 268
posted March 09, 2005 08:49 PM  
Can you tell were the fuel is coming from. If you sucked a piece of junk into the needle and seat then it could do what you are describing. Sometimes when you use rubber fuel line and put it on to a fitting it can nock a piece of rubber into the line and its going to go straight to the carb an if their isnt a filter between where you were working and the carb then it will end up in the needle and seat. Also it doesnt take a very big piece of sand grit to hold open the needle. Unless your carb is cracked I would think something like this is the problem. This is just my opinion thou. Good luck!!

Dirt Maniac

Total posts: 102
posted March 09, 2005 10:17 PM  
I had the same problem on my 4412 and it was due to the needle and seat being improperly adjusted! It looked like a lake down in the intake manifold!

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