Trouble shooting time hesitation

[genolan]

Have been driving a lot lately and the car has been running real well until tonight. I took it to the store and came out an hour later and she started right up got at about 2k rpm she bucked and a slight pop out the exhaust, I punched it and it hesitated then took off and ran strong. Started from a stop and the same thing and repeated it at least 10 times with the same results. There was no smoke or strange smell just hesitation, at ideal it runs fine.
Thanks in advance!!

[lippy]

If it was running fine before than your carb should be adjusted properly. I'd start with the ignition timing, and inspect the plugs. If your carb was not adjusted before that could be idle mixture or accelerator pumps, I think.

[bobcowan]

Pull off the float bowls and check in there for debris or schmutz holding the needle open, or clogging a jet.

[genolan]

Good idea Bob, Any idea where the fuel filter is? I looked to see if there was any filter on the fuel line or near the carb but nothing. If it was junk in the carb wouldn't it bog all the time when I get it over 3k and punch it it all is well.
The carb was adjusted and was running real well this just popped up out of the blue. I was just beginning to have fun!!

[jhv48]

Do a search on cleaning out the air bleeds!

Sure sounds like dirt in the fuel/carb. Below 3000 rpm, you're running on the main jets. When you punch it, the secondaries kick in. Check the primary main jets for obstructions.

[bobcowan]

Over 10 years ago (last time I had a carb) the same thing happened to me. Sudden and dramatic change. I went through the entire ignition system - twice.

Then I took the carb apart. I found a piece of debris stuck in one of the main jets. Removed that, put the bowl back on, and it ran fine again.

As to where the fuel filter is, it could be almost anywhere. It should be as close to the carb as possible, though.

[Rick Parker]

If the drop in rpm is like a light switch off and on sharply it is probably electrical, if it is more like a "bog" then it is fuel system related.

[mln385]

Originally Posted by genolan

Good idea Bob, Any idea where the fuel filter is? I looked to see if there was any filter on the fuel line or near the carb but nothing. If it was junk in the carb wouldn't it bog all the time when I get it over 3k and punch it it all is well.
The carb was adjusted and was running real well this just popped up out of the blue. I was just beginning to have fun!!

Check under rear of car by fuel tank for the filter.

[GLS-BDR226]

As min385 posted, it's in the line between the tank and fuel pump. Located in the rear driver's side. Mine had a cheap clear fram filter that let debris get into the carb. I'm replacing it with an Earl 85 micron in line filter.

[genolan]

I just finished playing golf and took it out again and this is what it's doing

1) Starts right up but unless i'm pumping the gas it stalls.
2) At 3k rpm it's running fine and no loss of power. Punch it at 3k and it's fine.
3) At 2k steady state it's bogging and hesitating bad.
4) If i take my foot off the gas it stalls.

If the jets have dirt in them wouldn't it restrict gas flow at higher rpm also?
I don't think the secondary are involved at all

I have all day tomorrow and wanted a plan of attack.

Carb main jet?
Gas filter?
Any thing else?

[jhv48]

Yep, could be timing not advancing fast enough. Pull distributor cap and check advance mechanism for smoothness. Rust can form relatively fast. If vacuum canister, check vacuum line as we'll.

Do you have a choke? Are you sure it's opening completely soon enough?

[Gaz64]

Blocked idle feed restriction.

What carb do you have?

[genolan]

The carb is a holly 770 street avenger with vacuum secondary, Remember it was running great so the timing was set correctly and so was the carb. I can I tell if it's the idle restrict and how can I fix them?

[genolan]

The choke is fully open and the distributer is a mechanical advance, Would the idle set screws help if I opened and reset them? Maybe that would clear and junk stuck in the idle circuit? Not really an expert on Carb's

[FWB]

Originally Posted by genolan

The choke is fully open and the distributer is a mechanical advance, Would the idle set screws help if I opened and reset them? Maybe that would clear and junk stuck in the idle circuit? Not really an expert on Carb's

if you hold the choke closed will it idle then?

are you close to Marotta's? either take the car or the carb there.....they'll be able to take care of it

[genolan]

Originally Posted by FWB

if you hold the choke closed will it idle then?

are you close to Marotta's? either take the car or the carb there.....they'll be able to take care of it

Nope it still stalls with choke closed, Who or what is Marottas's?

[FWB]

hot rod auto service...they are good
406 River Styx Road
Hopatcong, NJ 07843
Phone: (973) 398 3434

if it ran with the choke closed i would have leaned towards a new power valve.....but i'll chime in with the debris in the carb. spray some carb cleaner into the airbleeds in the top of the airhorn to see if they have any funk clogging up the works

[genolan]

Yea that was what I just did about an hour ago with no difference, This Sparta shop I Google and couldn't find it any more details

[FWB]

they did all the fabricating on my car when i went from a small block to a big block.
C-6 trans to AOD.

[genolan]

Originally Posted by FWB

they did all the fabricating on my car when i went from a small block to a big block.
C-6 trans to AOD.

Do you have an address or phone number?