Still struggling with car at idle after 8 years

[gundee]

On 8/18/2024 at 8:38 AM, jalexquijano said:

Lets see if i can explain this better. Step by step:

1. Crank the engine with the choke pulled.

2. Let the choke on for 1 to 2 mins.

3. Drive for 20 mins

4. Suddenly get trapped in traffic jam and temperature needle raises to 3/4

5. Rpm needle starts to go up and down between 900 to 1000 rpm

6. Once traffic is clearing i accelerate and engine starts misfiring with hesitation simulating coughing.

This is the best written explanation i can give.

I do not understand needing a choke on for 1 or more minutes. In that climate where you live.

Use to start only if needed then shut off.

If that was my car I would have a radiator shop test and recore it if necessary. 

I had to do that on mine. But now you can buy aluminum radiator replacements for 240Z's.

It may be cheaper to buy one of those if the old one is bad.

You also may have one of those old style water pumps with impellers that rot away and cannot move water anymore.

You want the better type with cast impellers. 

Cooling systems should be in perfect shape in your climate.

[jalexquijano]

7 minutes ago, gundee said:

I do not understand needing a choke on for 1 or more minutes. In that climate where you live.

Use to start only if needed then shut off.

If that was my car I would have a radiator shop test and recore it if necessary. 

I had to do that on mine. But now you can buy aluminum radiator replacements for 240Z's.

It may be cheaper to buy one of those if the old one is bad.

You also may have one of those old style water pumps with impellers that rot away and cannot move water anymore.

You want the better type with cast impellers. 

Cooling systems should be in perfect shape in your climate.

For the sake of order. I closed the jets and dialed them back to 3 turns clockwise each looking from above meaning the jet goes down. I have taken pics the fuel jet closed and opened to 3 turns each. Carbs balanced and rpm at 900. Should i go for a spin just as it is or should i put the air filter on?

[jalexquijano]

Should i test the car again and then use the color tune to fine tune the fuel jets?

[kully 560]

I would remove the ballast resistor and install a 3 -ohm coil, and then disconnect the choke cables completely and then use the color tune and rebalance the carbs !

[gundee]

I have used the pertronix ignition with 1.5 ohm coil and ballast resistor.

Worked just fine. No issue.

[jalexquijano]

Test drive around the corner cylinder 6 5 and 4, 3.25 turns clockwise in each carb. No traffic jam test yet and without the air filter on.