The plastic carburetor insulator on the GXV160 and the chonda clones of it, is quite distinctive. Here is a picture of the chonda 163 cc engine (same as GXV160 - this particular one is branded Rato) on my Ryobi pressure washer:
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I've put a red oval around the carburetor insulator. It is 15 mm thick, and has a larger flange on the carburetor mounting side. The GXV120 and GXV140 insulators are only about 6 mm thick, so you can identify a GXV160 clone from a couple of metres away.

Incidentally this engine has a Ruixing carburetor. The engine works perfectly, as I would expect considering it has only run 2 hours.

At this point I don't know whether your mower has a GXV120 or GXV140 chonda. The way to tell the difference, if you have the carburetor off, is to look at the intake port, not the gasket. The standard gaskets Honda sells are D shaped for both engines.