Is there a standard way to test a decompressor valve removed from the mower? I've done it by attaching some fuel line to the top of the decompressor outlet and sucked some air , the valve shuts so it seems ok but when i try the valve on the mower, it doesn't work. Is this the correct test or do i need to do something else?
It will need the air suction on the mower to be enough when it is cranking over.If you can suck it closed then it will be fine.If it doesn't on mower then maybe it is not connected to the right spot on the carby.It does sound like it's working to me.
Check the hose going to it is not blocked or restricted and make sure the connection on the carby end is clear. Although having said that the compression of a motor should be enough to force it shut. I'm assuming you're talking about the one on the 125 you're restoring with the G3 carb. Also make sure the fitting on the manifold is not loose and sucking air from around there. If its leaking it wont help your situation. Air likes to take the path of least resistance.
