Technical Weber 32/36 Jet Advice

Alright all you carburetor wizards - I need some help. I've got a DGV that won't idle without the idle screw turned in way too far. It's probably 6 turns in to get a good idle. What is happening is that the car is auto-dieseling on every shutdown because the throttle is open so wide.

So, I think I need to increase my idle jet size? Here is what I have now:

(Primary / Secondary)
Idle Jets: 75 / 60
Fuel: 145 /145
Emulsion Tubes: F50 / F50
Air 160 / 160

I've rebuilt the carb and it seems to be clean everywhere. Vacuum seems to be good. Float level is in the band. Pump pressure is regulated to approx 3 lbs. So, I think I've hit everything else.

What do you suggest? Thanks in advance.

 

What engine? Idle rpm? Vacuum? Idle mixture setting?

 

How high are you above sea level? (al***ude)
This is the first consideration. There is a chart on this carburetor, ('DGV' Weber site) and at the bottom of the page there is info as to what was originally in there, so one can make sensible adjustments from comparisons. (what you have vs. what IT had)

There are gradients as to jet size reduction correlation with al***ude above sea level...

I used a pair of these on a 221" flathead V8 a few years ago. (the parts bin at my BMW dealership gave up a few that were replaced by the 'new Fuel Injection techs' that condemned the carburetors, when the problem turned out to ignition, EGR valves, etc.)
Parts mgr. said "Take 'em, they're going to junk anyway..."
Hindsight says I could have used three!...But it ran great.

 

Wow - now that's a great BMW story! I usually leave our dealership just feeling a lot poorer. Great find.

To answer your questions:

Al***ude: 10' above sea level
Engine: GM 4-Banger 181 w/ 153 head
Idle: ~ 800
Vacuum: ~ 15 in

Thanks guys.

 

How many turns out is your idle mixture screw?

 

Have you adjusted your idle mixture screw ?

 

Ok baseline adjustments. Set idle screw 1 1/2 turns in. Screw idle mixture screw in until it bottoms out. Do not use force as the screw has a taper that goes into a hole. Then back out screw 2 turns. Adjust both screws until you get an even idle, if you need to adjust either screw more than one turn either way I would suggest your idle jet is blocked. Martin.

 

Yes, the idle mixture is about 1 1/4 turns out from the bottom, so I think its okay.

 

Try tuning using these instructions, in the written order:

http://www.carburetion.com/Weber/adjust.htm

I set the baseline on my 32/36 using those. The wideband Oxygen sensor indicated that it was so close that I only need to go up one jet on the primary.