Demon float setting or what would cause this?
Thread Starter
Safety Car
Joined: Oct 2000
Posts: 4,282
Likes: 172
From: Lake Wylie, South Carolina
Demon float setting or what would cause this?
Well I got to drive it down the driveway this weekend a few times. Seems to have gobs of power and is very responsive. Has been firing right up and idling around 850 without problems for a couple of weeks. now all of a sudden I am getting excess fuel dripping down the boosters while running and the car want stay cranked\hard to crank. What would cause this to happen out of the blue???? The Demon instructions say that fuel dripping from the boosters is a sign of to much fuel pressure or an improperly adjusted float. Fuel pressure is a constant 6-7 psi with a manual pump so that should not be the issue. And I have never touched the floats. Any ideas on why this just started happening?
Thanks
Wade
Thanks
Wade
Drifting
Joined: Sep 2004
Posts: 1,959
Likes: 1
From: North Bend Ohio
Have you made any adjustments to the idle speed or timing lately? The reason I ask is because retarded timing will force you to run the idle speed higher in order to keep the engine running. This can cause nozzle drip.
BigBlockk
Later.....
BigBlockk
Later.....
Le Mans Master
Joined: Apr 2000
Posts: 5,202
Likes: 10
From: cincinnati ohio
St. Jude Donor '09
Demon carbs have had quality control problems, particularly machining debri blocking passages etc. Fix is to dissassemble clean 
Last edited by yellow 72; Jul 17, 2006 at 10:15 AM.
Race Director
Joined: Sep 2004
Posts: 11,874
Likes: 263
From: Arlington Va Current ride 04 vert, previous vettes: 69 vert, 77 resto mod
look at the site glass on the bowls to determine float level and see where it is.....sometimes the additives to the fuels can make a difference when they change for the differeent seasons....so that would be a place to start...both of the site windows should be the same and probably below the 1/2 way rib, mine are set to the lowest rib
Race Director
Joined: Nov 2000
Posts: 11,872
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From: Waterloo ontario Canada
It sounds like a leaking needle and seat to me. Like someone said check the sight glass on the side and if it is too high remove the needle and seat with a screw driver and 5/8th wrench, blow it out and replace and adjust. NO big deal.
Junk often gets in after a new installation. It is common to have problems until you get a few miles on the system.
Junk often gets in after a new installation. It is common to have problems until you get a few miles on the system.
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From: Cape Cod, Mass.
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The Demons are configured alot like Holleys. It sounds like you may have some dirt in one of your needle valves. Pull both the primary and the secondary needle valves and blow them out, re-insert them and re-adjust your float bowl levels. This happens frequently with the Holley on my 65. The Demon on my 61 has never done this but your symptoms sound too familiar. Good luck.
Thread Starter
Safety Car
Joined: Oct 2000
Posts: 4,282
Likes: 172
From: Lake Wylie, South Carolina
Thanks for the advice guys I will do that tonight. It makes sense that I sucked some dirt in there as the tank has not had fuel in it in several years. It is also possible that when I installed my braided line from the tank to the pump and pump to carb that I did not get all the wire fragments out when I cut the line and installed the fittings.
BTW for those who have been following my progress. THIS THING IS GOD AWEFUL POWERFUL!!!!!
I did not remember how much torque a BB actually has. I barely popped the clutch and the car felt like it was going to swap ends with me...... 
Thanks
Wade
BTW for those who have been following my progress. THIS THING IS GOD AWEFUL POWERFUL!!!!!
I did not remember how much torque a BB actually has. I barely popped the clutch and the car felt like it was going to swap ends with me...... Thanks
Wade
Race Director
Joined: Nov 2000
Posts: 11,872
Likes: 12
From: Waterloo ontario Canada
Originally Posted by BlackRat
BTW for those who have been following my progress. THIS THING IS GOD AWEFUL POWERFUL!!!!!
I did not remember how much torque a BB actually has. I barely popped the clutch and the car felt like it was going to swap ends with me...... Thanks
Wade
It never ends.
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