How to rebuild Walbro 4 cycle carburetor

Petrol: Walbro carburetor problem - H needle has no effect

Hello
So the second contribution was really ultrasonic bath because the carburetor must be able to go in there
still sit something that does not come off.

Here is a video of how a carburetor is professionally overhauled. There is also an extra one
Parts set

Here is a cross-section of a Walbro carburetor to show the function



The number 8 is the throttle valve 20 is choke 9-11 The holes for idling and transition with L-needle 13. The 19 is the nozzle for
Full throttle with H needle 18.
It can of course be the case that someone has turned the needles too hard, then the seat is defective
can also happen at the idle needle. If the seat is defective, too much fuel comes through or you can no longer turn leaner.
You have to locate the channels as in the video and try to blow through there when the needles are closed or cross-check
Passage when the needle is open.
Actually, the Walbro carburetors are very simply knitted parts that are easy to handle if you know how they work.

Pig stupid question maybe the spring unhooked and the throttle valve in the wrong position?

Greetings Bernd
Last edited: