I have looked through several Honda engine lookup sites and I cannot find any information about this engine on a Honda Harmony 215 mower. The serial number is GJAB-7174612 and on another spot, it says the engine family is THN135U1G1RA. I know it is a 135 engine.
Perhaps one of the owner’s manuals listed on the website linked below will be for your machine. If so, I hope it contains the information you are looking for. If not, let me know and I will keep digging for one that does.