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Holley carb float problem

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Old Jul 31, 2010 | 12:51 PM
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Default Holley carb float problem

Hi 327-365hp, holley 2818 carb replacement (700cfm).

Issue I had was always up top at 5500rpm, the power would kust drop or flutter....at fast acceleration it would do the same thing (pegging the throttle).

Now I did adjust my front and rear floats a while back and when doing the rear float, it was difficult to adjust becasue everytime I tried to undo the top nut, it would spray out allot and leak. So i left as is for the last few weeks.

Well today I tried to tackle the rear float again, this time it let drain out (without the car started). I turned the screw all the way down to ensure the float was at the lowest point. Went to start the car, and it did'nt start....I floored the peddle to assist a couple of times and nothing, won't even start anymore. The intake was puddled with fuel so I decided to stop and ask the pros!'

Can turn down the float all the way cause this majore leakage and no start scenerio?

Not sure where to go from here....

thanks
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Old Jul 31, 2010 | 02:35 PM
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well took the rear float needle out (not sure if thats what it's called) sprayed it with some cleaner, put it back...the car started but after a spin, the rpm now drops to 100 or zero when I put the clutch in..or come to a stop??? I need to figure out to see where this float is...not sure if this is causing the new problem but most likely it is. Still have eratic power problem above 4K now instead of 5.5K?
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Old Jul 31, 2010 | 04:00 PM
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well got both floats nicely leveled...no stalling at stops....but the sloppy accelration still exists at high rpm...if I go gradually on the peddle it ain't so bad but still drops at 5K
any ideas?....come on guys, its like I'm talking to myself here..lol
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Old Jul 31, 2010 | 04:42 PM
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1st the 365hp is good for 6500+ rpm. They rev like crazy. Start with tuning to the factory specs. Check the usual stuff, plugs, points, timing, vacuum advance. Set your idle mixture with a vacuum gauge. Check the accelerator pump and fuel supply. You could be suffering fuel starvation, dirty filter, pump failing, dirty carb.
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Old Jul 31, 2010 | 04:44 PM
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Also make sure valves are adjusted properly.
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Old Jul 31, 2010 | 05:03 PM
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This may sound stupid but is there allot of fuel to control when taking the fuel filter off....I never took one off before is there a trick to make sure I get the fuel out of the line or is it a short flow over and then its done?

The filter is new but god knows my tank may have had some sand left in the tank....

Timing was done to spec a few weeks back.........

I checked my throttle pump and it looks like it has zero clearance, not sure because I'm only using a pc of sand paper as a gauge. But it seems to have no play.
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Old Jul 31, 2010 | 05:16 PM
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At any of the time you were having trouble, was there a backfire through the carb? If so, you may have blown the power valve. That would explain the lazy throttle response.

As far as the 5K rev limit, I had the same problem until I switched to a new coil. The old one would give up about 5500. I chased that problem for a couple of months. With the new coil, I can rev to the moon. Just to check, I put the old coil back in and the 5500 rev limit was back.

If not the coil, could also be points bounce (if you are running points). Unless you are using hi performance points, the imported ones you get today can't do high RPM.

Good luck.
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Old Aug 1, 2010 | 12:50 PM
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Originally Posted by count
I checked my throttle pump and it looks like it has zero clearance, not sure because I'm only using a pc of sand paper as a gauge. But it seems to have no play.
The accelerator pump adjustment MUST be made with the throttle lever at the wide-open-throttle position, and the little lever on the pump depressed; in that state, you set the clearance between the spring-loaded adjusting bolt and the pump lever at .015". That will give you an instantaneous pump shot from the shooter with the slightest movement of the throttle lever.
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Old Aug 1, 2010 | 01:38 PM
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I did have a back fire a few times...its not consistent...

The distributer is points, still on the fence about switching to electronic, are saying the electronic ones will have problems in the higher RPM's?

I'll order a new coil tommorow....cross my fingers this is it. Seems like an easy troouble shoot!

Once I get some feeler gauges from work I can properly set the accelerator pump.

thanks guys
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Old Aug 1, 2010 | 08:18 PM
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So I took her out for a spin, and tried slowly building up to 5500 or so, the wackiness continues......so I assumed this meant electrical issue but then I did the same thing in 3-4,
and it actually went to redline with no issues???? 2-3 with a very slow build up and it was wacky again....maybe the 3-4 was just a fluke
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