'67 Holley 3811 secondary flooding

[William F.]

Know there's a lot in archives about Holley flooding, but this seems to be to be a little different. When my '67 L36 with correct 3811 carb is parked on a slight incline, nose up, or jacked up in front for a while, after starting, fuel can be seen flooding out the secondary only venture discharges. After it dies a couple of times and I drive it a little while, everything smooths out with no more fuel flooding from secondaries. Have pulled secondary bowl and checked float level- a little high. Holley book spec is 13/64" at heel of float with bowl inverted.Is this the same Chevy specs? Would you just lower the float level slightly, mabe to 1/4" measured same way or what else could be causing problem? No trash in fuel I drained from bowl. Will check needle/seat.
Thanks in advance

[William F.]

Re: '67 Holley 3811 secondary flooding

Talked to Holley tech. They said specs call for 11/32" measured at TOE of secondary float with float inverted. Mine seems correct or very close. Would you lower it a bit or suspect needle/seat as problem?

[Timothy B.]

Re: '67 Holley 3811 secondary flooding

William, If the car is parked is such a way that the fuel moves rearward in the bowl the float drops and lets more fuel in. Does this sound like that's what is happening?

I don't think it will hurt anything to lower the float some and see how it works.

[Stephen L.]

Re: '67 Holley 3811 secondary flooding

Make sure the float doesn't have a leak. Had one with a small amount of fuel in it and it gave me fits... kept setting the levels but failed to shake the floats to find the fuel sloshing. Not much fuel but enough to upset the adjustment.

[Peter M.]

Re: '67 Holley 3811 secondary flooding

Hi William,I had a similar problem. I lowered the float level a small amount and the problem went away. I can't remember how much, so you will have to try lowering it in steps. Firstly as Stephen says check the float.Regards,Pete

[William F.]

Re: '67 Holley 3811 secondary flooding

First of all, is it normal for transfer tube to overfill secondary bowl when car is parked on incline with nose up even if everything is set up properly or should the needle and seat prevent this overfilling?? I found correct secondary float settings: Chevy says 5/16" at TOE of float with bowl inverted; Holley-11/32"-mininmally different from 5/16". I installed new needle/seat and set float-it was a little high. Will see how it works. But, what about the overfilling of secondary with car in front end up position??

[Timothy B.]

Re: '67 Holley 3811 secondary flooding

William,

With the car in that position the fuel will run to the back of the float bowl and the float could drop and let some fuel in causing the condition you report.