Zenith carbs - accelerator pump problem

[bizz]

Hi all,
After inspecting my accelerator pumps i've noticed that the rear carb only dribbles fuel on open throttle. The front carb flows a nice steady stream.

Is there a simple way to clean/service the accelerator pump without removing the carburetor? I have a feeling that this blockage is causing the stutter when throttle is applied.

Thanks,
Ben

[Falkenberg]

The accelerator pump applies fuel through the small curbed nozzle that you can see going in to the venturi. If that is the one just dribbling, then it is probably blocked. They have a very small diameter. You can remove it, it is pressed in the housing just not to drop. Just don't drop it by accident in the carburetor. When you have it removed, see if you get a lot of fuel from the pump. Check the nozzle, clean it with compressed air, the best way is to apply air on the side where the fuel should come out. Put it back, it might block again after some time if there is dirt in the carburetor. Use a good fuel filter.

[bizz]

The accelerator pump applies fuel through the small curbed nozzle that you can see going in to the venturi. If that is the one just dribbling, then it is probably blocked.

Yep that's the one. I wasn't sure if it came out - are they difficult to remove?
I assume it just presses back in place? I just want to ensure i don't damage it.

Use a good fuel filter.

Sorry to be a complete noob, but where is the fuel filter mounted in the carbureted cars? I'll do some searching to see if there's any info on this elsewhere.

Thanks again

[Falkenberg]

Good question about the filter.. There is a filter in the pump, and there are filters in the carburettors. Those are all wire mesh type. I am not sure if there is another one. So I just added an extra in-line filter in the line that goes to the fuel pump.

The nozzle is easy to remove, and you can press it back in place easily with little force. Just don't drop it in the manifold.
If you don't manage to get it out, you might want to remove the ring thing venturi part where fuel comes out that is in the middle of the intake, it's just one screw extra to remove.

[bizz]

Ah ok, I thought there should be a filter inline, i will add one in for good measure.

Thanks for your advice, i pulled the nozzle out & gave it a clean, there's now a solid jet of fuel leaving the nozzle rather than the dripping - we will see how it goes tomorrow on the drive to work