Fuel System: Engine idles rough, sputters bad when throttle opened up

[jostanton1]

I have a freshly rebuilt 289. The timing is set, dwell at 30 to start and the valves adjusted to .026 cold. It starts right up, but has some miss and when I open up the throttle, it bogs down big time and mis-fires. Although I have been out of practice for 20 years, I think I rebuilt the carburetor correctly! But I may have missed something. I can't seem to find any vacuum leaks as well. Any thoughts why I can't get this thing to smooth out rev up like a new motor should? BTW, the carb is a 2bll Stromberg WW.


Thanks.

[StudeRich]

Was it running strong BEFORE the Carb. Rebuild? Knowing that, would rule out many other issues including Electrical ones.

[christophe]

You should hook a vacuum tester to it. The readings will tell you the whole story.
Nice day to all.

[doofus]

More info please, did this start right after the re-build or later.cross wired? bad fuel pump, dying coil or condenser? more clue's please.Luck Doofus

[turboreichel]

verify you have the firing order correct , its easy to get a couple of plug wires mixed up will cause miss/bog and will still start idle well enough

[jostanton1]

The engine had blown head gaskets when I purchased it and ran bad. So I can't compare with that after the rebuild. It has a new coil and condenser, points cap and rotor. I suspect I must have done something wrong in rebuilding the carb. I'm just trying to pinpoint what I may have missed. What should I look for in a vacuum reading?

[jostanton1]

18436572 All checked.

[RadioRoy]

Have you done a compression check with the new head gaskets?
You haven't mentioned the year of the car. Does it have a PCV valve?

[jostanton1]

It's a 64 Hawk with full flow and PCV valve. Not done a compression check yet. It was bored out and a valve job done. At this point, I just assumed it should have just ran fine off the bat. Pretty much everything is new. Reground cam, new lifters, pistons and the crank polished. And all new bearings.

[RadioRoy]

If the PCV valve is stuck or corroded, that will affect the fuel to air ration significantly.

[jostanton1]

My PCV valve was bad and leaking. I plugged the inlet at the throttle plate and it made no difference. Still wont rev up.

[Dwain G.]

What's in the tank for fuel?

[christophe]

What should I look for in a vacuum reading?

Here is a link to an example:https://www.classiccarrestorationclu...oubleshooting/
There are many others. You just have to google vacuum tester readings.
For what it's worth, I've seen such troubles caused only by defective spark plugs.
Nice day to all.

[doofus]

Starting to sound like a really lean mixture. when you cleaned the carb did you remove the main jets, takes a special tool most of the time. a lot of Sif,Fonk, and Gradeu collect above the jets. Luck Doofus

[jostanton1]

I am taking the carb in for a professional rebuild. I think I blew it on my rebuild as I could not remove the jets. Thanks everyone for the tips!