Thread: carb flooding

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The 23 T has a strange problem.

Prior to taking the car apart and rebuilding it, the fairly new Holley 600 single feed with vacuum secondaries would leave a puddle of fuel on the intake.

After rebuilding the engine, blowing out the carb, and putting it back on...it started doing it again.

Then, while running, the carb started flooding on the secondaries off and on.

I pulled it off and slapped the 600 from my 69 Camaro on. I did not note any leaking on the intake over night, but it started flooding on the primary side off and on while running.

I rebuilt the 600 using all new gaskets, needle, seat, etc.

Set it all back up and had great success for a day or two. Then, it started leaking out again.

Yesterday we tried running it around the block. Every couple of minutes the primary venturies would just start dripping and flooding. I could clear it out by hitting the accelerator and holding it down for a bit.

I have a new fuel filter, and it is a standard stock style mechanical fuel pump. I have new fuel line to to the tank.

Now...on the T, the gas tank is higher than the carb, or as high as the carb. Does this create a problem?


What gives?

I talked to the Holley tech line and did not get any real solid advice, other than to try the rebuild...which I did.

Considering it has done this on both carbs, and a new set of float needles...??????

Thoughts?

Trash in the needle & seats, worn needle & seats, Floats that are absorbing fuel.

Hi 69myway

Hworrel said it all. If you have already ensured that the needle and seats are new and clean, you are left with two other possibilities. If you have the tin floats, my guess is that one of them has a tiny hole in it and as time goes by, they slowly take on gas and start sinking, thus allowing more fuel into a bowl that is already full. If you shake the float, you will hear fuel sloshing around in them.

Secondly, have you checked the settings of the float levels? The observing hole is on the side of the bowl and has a flat slotted screw in it. Remove it and then start up your vehicle and check to see if the gas is flowing out of the side. If it is, set the level lower. If you do not know how to do this part of operation, just ask. Furthermore, if you have faulty floats as described above, then you will never be able to set this level correctly.

Thirdly, your fuel pump maybe over zealous. Install a fuel pressure gauge to see what fuel pressure you have. 7 psi is about the maximum the floats can handle.

Also, If it has the foam type floats these tend to absorb fuel, only way to tell is pull em and weigh em although I can't recall what they should weigh ( I could tell by feel) if your suspicious push your thumbnail into it and if fuel seeps out they are absorbing fuel of course ya just ruined it and will need new ones any way.
Reading your post again I might suspect too much fuel preasure I think 9 lbs would be the max with carbs...

Well, I yanked the floats. It had the plastic kind. The front float seemed to be bent at the pivot.

I had a set of metal ones in an old junk carb. I cleaned those up and swaped it out. So far so good.

Get this. It sat and dripped since last night. When I got home from work I glanced down the carb to see both front and back with a steady leak!

It hydralocked the engine! I had to pull the plugs and drain the gas out of the cylinders, then drain the oil which was about three quarts over full with gas!!!!!!!!!!

I guess that is the negative part of having the tank as high as the carb. Where there is a float or needle/seat problem, it can pretty much drip out.

Now, we let it sit overnight and see how it is after work on Tuesday.