Weber secondary help/advice needed

[EricH]

This is a 32 DMTRA that I've put on a 1500 motor, but likely the answer will be the same for just about any Weber two-barrel progressive with a manually activated secondary.

I'm having trouble getting the idle mixture/speed sorted out... and then I discovered that if I put my hand over the secondary barrel at idle, the motor would stall. Now that doesn't sound right - the secondary isn't supposed to be doing anything at idle. And because I happen to have another sweetly running X1/9 with the same carb, I could try the same test on that car - and it idles just fine even when I block the secondary.

1) Does this mean that my secondary throttle isn't closing all the way?
2) How do I fix it?

 

[wannabfast]

hmm i would start from square one and rebuild the dang thing
might find that some of the jets might be gummed up

 

[EricH]

Already did (sigh)

hmm i would start from square one and rebuild the dang thing

That's what I did before it went onto the car... stripped it down to the body, soaked it overnight in carb cleaner, blew out all the passages, new gasket, needle valve, float, fuel strainer, accelerator pump diaphragm. Fuel is coming from a reconditioned tank from Matt, all fuel lines, filter, and fuel pump are new.

I'm just damned if I can see what I can do the linkage that would keep the secondary a bit open, or fix it if it was.

 

[wannabfast]

did you put the mechanical secondary link back where it was supposed to go? i remember that my 32 datra the link went on one side and it was open and forced the primary shut.. and if it was positioned the other way it would operate normally

 

[EricH]

Aha... Found the answer

(and I think I could learn to like bump mode too, BTW)

On the linkage side of the carb, towards the front, there's a setscrew reachable from the underside of the carb - it's the idle stop for the secondary throttle plate. It works by bearing on a tang on the secondary's linkage lever.

It was in too far, holding the secondary open enough that the car was idling on the secondary transition circuit. No wonder the idle mixture screw didn't seem to be doing much for me...

 

[wannabfast]

so its fixed now? yay