Still struggling with car at idle after 8 years

[Mark Maras]

3 hours ago, gundee said:

The next thing while the dome and  pistons are removed you can turn the jets knobs to the full

up position. Then look. Do they look the same depth. Are we starting with both jets at the same position.

For example turning a jet knob 2-1/2 turns down does not mean they are the same if the starting points are different.

Did you say these were Z-Therapy carbs?

@jalexquijano As mentioned above, check that both needles are installed to the same depth. If they're not, it would explain needing an extra turn down on one carb. The other possibility is one or both floats aren't adjusted properly.

[jalexquijano]

11 hours ago, Mark Maras said:

@jalexquijano As mentioned above, check that both needles are installed to the same depth. If they're not, it would explain needing an extra turn down on one carb. The other possibility is one or both floats aren't adjusted properly.

Mark, those needles were replaced by ztherapy in 2014. Do you want me to unlock them and change their height?

[jalexquijano]

On 10/29/2023 at 5:15 PM, gundee said:

I agree with you. I think one carb is lean and one is rich for some reason.

The motor itself I think is good. So lets try to find a way to get the plugs to match.

Lets all take a look at the carb and manifold picture if we can get one.

Also do you have a carb sync tool?

 

 

[Mark Maras]

2 hours ago, jalexquijano said:

Mark, those needles were replaced by ztherapy in 2014. Do you want me to unlock them and change their height?

  We need to confirm the needles are installed in the pistons to the same depth. Measure from the piston bottoms to the tips of the needles. No need to unlock them and change their height if they're the same.

[jalexquijano]

5 minutes ago, Mark Maras said:

  We need to confirm the needles are installed in the pistons to the same depth. Measure from the piston bottoms to the tips of the needles. No need to unlock them and change their height if they're the same.

Let me get home after work and i will measure and post pics. 

[gundee]

Is this doing anything?

[jalexquijano]

On 11/21/2022 at 3:22 PM, Mark Maras said:

 Is your clockwise adjustment your view from the top of the carb or is it looking at the adjustment screw from the bottom of the carb? This makes a huge difference. When we describe turning the mixture screw clockwise, we're imagining looking at it from the bottom of the carb and we're leaning the mixture out. If you're imagining looking at the screw from the top and turning it clockwise, you're richening it. You could pull a dome and watch the nozzle as you adjust the height and tell us if the nozzle rises or drops when you turn it clockwise. 

From the top! Looking from the top always.

[jalexquijano]

9 hours ago, Mark Maras said:

  We need to confirm the needles are installed in the pistons to the same depth. Measure from the piston bottoms to the tips of the needles. No need to unlock them and change their height if they're the same.

Pics of needles and bridge first front carb and next rear carb. 3.5 turns clockwise. 41 to 42 mm from base each needle.

[jalexquijano]

More info regarding both remanufactured carbs by ztherapy. Needles have not been touched after ztherapy's work.

[gundee]

Now I am going to say the carbs are likely correct.

1. I do believe the rear carb responds to mixture adjustments as it should.

2. I believe the front carb is not responding to mixture adjustments like it should.

3. Lets get our heads around that front carb. What would make it lean? Excess  air is likely.

I no longer have SU's on my Z so I need to go by memory and years of working on British cars with SU's.

[jalexquijano]

Ok help me with this. We already solved the coil mistery now we need to get these floats adjusted to 2.5 turns each carb.

 

 

 

Edited November 1, 2023 by jalexquijano

[Yarb]

Might want to reach out to “ZTherapy” and ask what their base line settings were when they rebuilt your carburetors. You have the paperwork and I’m sure they would be happy to guide you through the process. Over time a lot of hands have been on the carbs themselves. Maybe it’s time to start from scratch with their direction. My two cents