Hey guys,

 

I've got a 4k with a webber carby on it

Sometimes it idles fine and some times it just wont idle at all.

As you drive along it will drive fine for a bit, then just bog down and die sort of thing for a few secconds and pick back up again.

 

Now, its either theres not enough fuel getting to the engine, i put a new fuel filter on it but for some reason its not filling it right up? i don't know if they are suppose to or not.

 

Or, Theres something wrong with the spark and its on firing a few cylinders.

i have no real clue but I'm heading more towards lack of fuel going through.

 

any ideas or help will be greatly appriciated.

 

Cheers Dan.

A leaf or a piece of plastic floating around in the petrol tank that can block the outlet occasionally...!

 

Does it do it when cold or warm? The filter will only fill up if you hold it up so the bubbles get sucked out, but they don't matter.

 

How about stopping the car the moment it runs rough and checking the fuel level in the carb, and compare that to when its running well.

 

It may be that sone fibre is stuck around the needle & seat in the float bowl adn it runs rich at the times it dies.

 

Better would be an oxygen meter up the exhaust pipe that told you when it was rich and when lean.

 

Do you want to start a "Weber Specs" thread and list what jets and chokes you have, along with cam & exhaust. Slowly we could build up a set of specs for the Weber carb that suits the 4K best, and a 'common troubles' list for them.

id guess dodgy fuel pump

Timing.

my kexx wagon had this type of issue i swaped out the neddle and seat (std carby thoe) new pump plugs and leads, only to find that it was the capacitor below

hope it helps

Edited October 24, 201015 yr by shaded_shadows_KE55

Little round thingy is a capacitor!!

 

I'd do a fuel pump pressure test, should be about 3 psi.