Noise that happens twice per revolution on my GX390 with pressure washer on it. Sounds internal to the engine. I’ve tried removing the pull starter to see if anything was hitting, then turning the motor over by the pump and it still makes the noise.
When cranking over with the electric starter or when it’s actually running you can’t hear anything (although the machine is pretty loud). Engine runs smooth. I’ve never run it low on oil, always check it before using.
Anyone seen this before? I’m just trying to avoid an engine tear down if I don’t have to.
I have found out the problem. I started with the process of elimination, first removing the push rod from the exhaust side to see if it would go away (potentially linking the decompression mechanism), sound was still there.
I then proceeded to remove the camshaft itself, and voila, noise was completely gone. It turns out the noise is created by the backlash between the cam and crank gears…not much I can do about it, I threw it back together as is. The engine runs fine but the noise was bugging me not knowing what it was.