C2 Holley Carb Flooding

[Ron Still]

I am having flooding problems on my 66 L79 with Holley 4160 List 3367 carb. Fuel is flowing out of the secondary bowl onto the throttle plates and leaks out past the throttle shaft/throttle plate all over the intake. I have heard about others with this same exact problem but have found no solution. I have replaced the needle/seat & adjusted the float level. What's weird is is seems to happen AFTER I shut down the engine, not why it's running. The one thing I have not checked is the float itself. Why would the fuel flow out after the engine is shut down???

Thanks,
Ron

[Jim T.]

Re: C2 Holley Carb Flooding

If your float is metal shake it to see if fuel has leaked in. If your float is not metal, discard what you have and buy metal float. You can buy them individually at auto stores like Auto-Zone etc. You may have to order it through some stores, but most can get it if they do not have it on the shelf.

[Wayne K.]

Re: C2 Holley Carb Flooding

Ron,

I think you have what is commonly referred to as Holleyitis. It seems to inflict most Holley carbs, some sooner & some later. I'll guess that if you remove the rear fuel bowl you'll find that the secondary metering plate (if your model has one)otherwise the metering block is warped. You can check this by removal and placing on a true flat surface. Also check the main body with a straight edge to see if that is warped. The fix is true up the surfaces or replace with new parts including gaskets. If nothing is warped and the float checks out including its setting (could be too high) I would assemble using new gaskets. Maybe things just needed tightening up but I doubt it. Please let us know what you find.

Wayne

[Ron Still]

Re: C2 Holley Carb Flooding

Wayne,
"Holleyitis"??? I call it "Paininthebuttist"!!! I have metering plate in mine, I will check this and main body for warpage. If this isn't it, I am completely out of ideas. I will post what I find out. Thanks!

Ron

[Clem Z.]

Re: C2 Holley Carb Flooding

if you have a metering plate you should also have a nirtophyl float because the brass float arm is too long and causes the float to bind up on the metering plate

[Gerard F.]

Re: C2 Holley Carb Flooding

Ron,

Here's two things to check before you tear into the metering plate:

1. Is the brass float loose in it's pivots, or bent too far forward towards the metering plate. I had the same problem and simply bent it back with my finger towards the back of the bowl. Don't bend it back too far to rub against the back of the bowl. This solved my problem.

2. Check the 4 air vents in the secondary air horn, make sure that they are clear and unblocked. Blocked vents could cause a siphoning of gas from the bowl into the air horn, especially after a hot shutdown. If you have to take the metering plate off you can blow air through the vents.

Try #1 first, that might be the easy fix, it was for me.

Hope this helps,

Jerry Fuccillo
#42179

[John M.]

Re: C2 Holley Carb Flooding

Ron, check to see if the torx screws holding the metering plate are tight. Sometimes with age the gaskets change and the screws need tightening. Been there.

[Rob A.]

Re: C2 Holley Carb Flooding

Ron,

I had a smiliar problem with my #3367. After simply removing the rear bowl and re-installing it, fuel leaked into the carb(when running). I removed the bowl and everything looked normal. I slid the float(metal) back a bit, reinstalled it and everything was fine..don't know exactly why that fixed it. I would try sliding the float towards the rear of the bowl before installing it again.

[Clem Z.]

applys to center hung floats only,not side hung *NM*

[Dick W.]

Re: C2 Holley Carb Flooding

And then again, the screws may be overtightned and warped the carb body. Big screwdrivers are #1 enemy of Holley.