Weber will not idle

[BMWDUO]

I'm finaly about to get my 69 GT on the road. I didn't do the original build so I'm not 100% sure of specs but it is a 1.9 with weber 32/36, fuel presure regulator & gauge, Jacobs Omnipack, and header. I rebuilt the weber and all should be good but it won't idle or run below about 1800 RPM. Going by both weber and factory info it appears that all hoses etc are in proper locations. The electric choke is working properly and timeing should be close. The car screams aon the road but shuts down when comeing to a stop. Disconnecting the distributor hoses helps but is not a total cure. After doing this I did get response from the mixture screw so it is no blocked. I also don't have the set-up specs for the omni-pack but think it would require some type of advance. Any help is appreciated. Its been almost 2 years and my wife wants HER car finished!!!!!!!!!!!

[RallyBob]

I'm finaly about to get my 69 GT on the road. I didn't do the original build so I'm not 100% sure of specs but it is a 1.9 with weber 32/36, fuel presure regulator & gauge, Jacobs Omnipack, and header. I rebuilt the weber and all should be good but it won't idle or run below about 1800 RPM. Going by both weber and factory info it appears that all hoses etc are in proper locations. The electric choke is working properly and timeing should be close. The car screams aon the road but shuts down when comeing to a stop. Disconnecting the disributor hoses helps but is not a total cure. After doing this I did get response from the mixture screw so it is no blocked. I also don't have the set-up specs for the omni-pack but think it would require some type of advance. Any help is appreciated. Its been almost 2 years and my wife wants HER car finished!!!!!!!!!!!

It sounds like either the idle speed screw is not turned in far enough (a simple solution), or perhaps your idle circuit is not working (a bit more involved to diagnose).

Make absolutely sure that there is no debris stuck in the idle passages or in the idle jet itself. I've seen a tiny fleck of dirt or silicone block the idle jet and the vehicle will NOT idle at all! Also make sure that the idle jet holder o-ring is intact and in place. Not having the rubber o-ring here creates a huge vacuum leak in the idle circuit only.

The other thing to look for is simply a general vacuum leak. It's extremely common and Opels seem more sensitive to vacuum leaks than most cars. Adding a large amount of unmetered air during the idle phase leans the mixture out so far many cars won't run at all.

[tekenaar]

It sounds like either the idle speed screw is not turned in far enough (a simple solution), or perhaps your idle circuit is not working (a bit more involved to diagnose).

Make absolutely sure that there is no debris stuck in the idle passages or in the idle jet itself. I've seen a tiny fleck of dirt or silicone block the idle jet and the vehicle will NOT idle at all! Also make sure that the idle jet holder o-ring is intact and in place. Not having the rubber o-ring here creates a huge vacuum leak in the idle circuit only.

The other thing to look for is simply a general vacuum leak. It's extremely common and Opels seem more sensitive to vacuum leaks than most cars. Adding a large amount of unmetered air during the idle phase leans the mixture out so far many cars won't run at all.

. . . in addition to what Bob said above, does carb have an ICO solenoid primary idle jet (Emission/Anti-Diesel) instead of a regular primary idle jet holder? If so, ICO solenoid spade terminal at its end must be connected to a switched 12V source . . . electric choke is a good connection point.

[opellane]

This has always worked for me. When a new Carb. has been installed and won't idle. Suspect a Vacuum Leak. Get some Gum Out Carb. Spray raise engine speed enough so it idles. Then Spray around Mounting Base and intake, heat shield, carb body,Intake Manifold to block,etc If the engine changes RPM's or stumbles,or races then that's where a Vacuum Leak could be present. Re-seal and or correct problem. The Vacuum leak will draw the spray into the engine. This Has always worked for me to pin point Vacuum leaks.
Like RallyBob Said : It's extremely common and Opels seem more sensitive to vacuum leaks than most cars.

[BMWDUO]

Have checked everything mentioned with no luck. What I have found is that the float level seems to be too low. Does anyone have level & drop specs for BRASS floats? All I can find in my books are for plastic and apparently they are different.

[BQS4]

Have checked everything mentioned with no luck. What I have found is that the float level seems to be too low. Does anyone have level & drop specs for BRASS floats? All I can find in my books are for plastic and apparently they are different.

This "may" be part of your problem, as brass floats are two shells soldered together. There may be some fuel leak into the floats, so you may want to order a plastic one.

[krewzer]

Brass float levels are to be 41mm and 51mm, plastic levels are to be 35mm and 51mm

Wes