Webers

[jamesnmlaw]

Time for a little spring tuning. I rebuilt the Webers over the winter. Valves are good, timing and dwell correct, plugs and wires are new, floats are properly adjusted, idle jets are clean, car warmed up, set the idle, did not disconnect the throttle linkage. Got out the synchrometers (have 2). The left bank each have right at 5 kg/h. The right bank each have 10 kg/h. So, lower the right bank to 5 kg/h, right? Tried the air adjustment screw (undid the locking nut) and turned the screws. Nothing. Took the screws out, didn't change the 10 kg/h. Tightened them all the way in, same result. Tried to up the left bank from 5 kg/h to 10 kg/h, nothing. Can't get any changes. All the left bank stay at 5 kg/h and the right bank stay at 10 kg/h.

Any suggestions?

The car sounds great, BTW.

Thank you, brains!

[Steve@Rennsport]

Hi,

Assuming that your throttle shafts are not leaking air, you either have a vacuum leak between the carb & manifold or some schmutz in an idle air passageway.

[zedsn]

I know that you are suppose to disconnect the linkage at each carb before you do any adjustments after the car is warmed up.

[1QuickS]

Assumptions at beginning of tuning are:

• throttle stop screws adjusted 3/4 turn open from throttles fully closed
• idle air correction screws are all closed
• mixture screws 1 3/4 turn open

Possibly the throttle lever arm has rotated on the shaft so the throttle valves are open even if stop screw is not touching tab on lever arm. Also, if your shaft coupling is not the later, cylindrical type then you could have an issue there but equal air flow indicates this isn't the case.

Typically a high air flow at idle indicates rich idle mixture; STE reading of 5-ish is typical for Lean Best idle mixture setting.

[jamesnmlaw]

Got the car at warm idle. Took a little carb cleaner stuff and sprayed around throttle body linkage at front and rear of right carb (10kg). Looks like it is rebuild time! Same results on the left bank, just not as much (5kg). Performance Oriented? Any other suggestions?

Thanks,

[zedsn]

Paul is the man for these carbs but he does have a waiting list usually.

[Indescikov]

Yes, Paul Abbott has the answers. His service is nothing but FIRST class.
Check out his web page for technical insight on how to maintain and tune your Webers properly

[snbush67]

Originally Posted by jamesnmlaw

did not disconnect the throttle linkage.

You have to disconnect the linkage, then balance the left and right banks to each other, then adjust and connect the linkage without upsetting the balance.


The reason you aren't getting any flow change is because the throttle linkage isn't allowing it.

[jamesnmlaw]

I'll try with linkage disconnected. Thank you for the tip!

If nothing, off to Paul.

[matthewb0051]

Take a look at this Wheeler Dealers episode on the Lambo Urraro at around the 33rd minute. Edd brings in a guy to adjust the Webers. Although the carbs are not the same configuration, the concept is the same. Worth a look.

https://www.youtube.com/watch?v=pet09myhAC8

I'm digging his Rod Stewart hair do.