Any Tricks for Leaken' Demons?

[bigiron]

I know, I know... this board loves Demons... but I'm begining to think they suck (and not just air)....

I have a half dozen of these carbs (sure are parrrty arn't they...) I have had problems with every single one of them...

The newest problem is... I have 2 775 race demons on my blower motor... you know... the kind that you can make into all kinds of other sizes... When I turn my pump on, it fills the bowls, and keeps on filling, and filling ..... and filling... and then starts filling the engine....

Ok... easy... adjust the floats you say.... done that.... change the o-ring on the float adjuster you say.... done that.... check the fuel pressure you say.... done that (I've droped it all the way to 3 pounds)

STILL LEAKS..... I have called Demon tech and was basicly told being that the carbs were out of warrenty it was my problem not theirs...

Now for the questions..... Has anyone experienced this behavior with these carbs??? (I'm beginning to think the shaft was machined to big or somthing...) Does ANYONE have a trick or cure or ANY idea what to try next??? Oh I've replaced the needle valves in one carb with a couple out of a holley that I know are good....

Both carbs do this and not all the time... but it is getting worse... It's gotten to the point that I don't even like to drive the car... you can't.... I find myself driving the wifes Mach 1 more and more AND THAT JUST AIN"T RIGHT...

[23T]

Have tried to cotact Don at FBO?

[70Barracuda]

Happened on Sunday. The needle had a tiny piece of metal holding it open. Gas overflow!

Call Don 503 627 0728 He's the MAN!!

[pishta]

Mine leaked too. Every other time I started it it would flood. Turned out the O ring in the seat assy sheared off a slice when it was installed and it was holding the needle open. It was a holley O ring and it was TIGHT when I installed it (tight as in it was getting cut when I was forcing it in). Is there a chance the BG O rings are smaller to fit a smaller bore? I dont know, after I picked out the sliver it didnt flood again, but I did sell it 3 weeks later to get one that would fit my future 451. Is the power valve gasket and diaphragm still good? Can you remove the sight glass and hold the float up with a pencil while you bump your electric pump? Thatll at least show if your needle/seat is any good. If that stops the fill, good news. If not, you may have the wrong bowl gasket or block gasket installed. You know, for the amount of Demon carbs out there, we sure hear alot of annoyances with them, dont we? I was going to get a 750 speeder but might go with a blueprinted Demonsizzler 850 TQ now. Still contemplating....

[jimm II]

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Have had really good luck; bought my Mighty demon off, Don who installed it on his engine and got in close . The only thing I've changed is jets up or down.....and I've used Barry Grant jets and NOT the holley.....So far I've had good Luck. Jimm II

[ehostler]

I've been very happy with my Speed Demon. Then again, I only have less than 200 miles on it. If I didn't go with a Demon, I would have gone with a TQ.

I did have a Holley 3310 (years ago). It had the same problems with flooding one of the bowls. It happend right after install. Turned out that somehow a blade of grass got into the fuel line. This blade of grass got trapped in the needle valve and wouldn't let it close all of the way.

[bigiron]

Got off the phone with Don... What a guy... boy get him talking and look out ... make sure you have a lot of time (well spent) when you call him...

I'm going to try a few things he told me.. and see if any of it helps. I've tried all the things mentioned here (several times..) to no avail... but I have to put aside a little time in the next week or two and see if I can't resolve this.

I have a new filter coming and new needle/seats. I'm old oilfield... if they can't get it they can't stay.... I just don't like the idea of sh!tcanning 2 $1000 carbs over somthing so stupid.

We'll see what happens in the next week or two...