Outdoor Power Equipment and Small Engines - Walbro LMK carburetor inquiry

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View Full Version : Walbro LMK carburetor inquiry


seabreeze
11-23-08, 02:12 PM
Could any of my learned colleagues tell me the purpose of the 12 volt electrical device attached to the bottom of the bowl of a Walbro LMK Carburetor. It appears to be some kind of solenoid device. I have limited knowledge of new fangled carburetor systems. Is there a way to test it's application ?
I don't seem to be getting any fuel to the combustion chambers.:wall:


30yearTech
11-23-08, 05:35 PM
It's an after fire solenoid. It does prevent fuel from being drawn up the nozzle of the carburetor when activated, so if it's not working you will not get fuel into the combustion chamber.

It's purpose is to shut of the fuel supply when the engine is shut down to prevent fuel from igniting in the muffler and causing a big "BANG". When the ignition key is in the on and start position the solenoid is energized and draws a small needle down and away from the nozzle, allowing fuel to flow.

The easiest way to test it, is to shut the fuel supply off and remove the solenoid, plug it in and make sure it's grounded and turn on the key and observe the operation. They are pretty reliable so if it does not work, check and make sure power is being applied and that the unit is not gummed up with varnish. They can be easily cleaned with some spray carburetor cleaner if sticking due to varnish or dirt.