I rebuilt my Honda HRX217K4HZA mower and have other threads on that topic. The mower now cuts grass just fine but I'm having trouble adjusting the engine speed. It runs fast on full throttle, like around 4000 rpm whereas it should be 3100. I use a tachometer while I mow to keep the rpm's down. I've tried a couple of things already but I noticed something about the auto choke that made me wonder. When looking at the thermowax device on my mower I noticed that the pin in the middle is fully extended out when I was reassembling the carb assembly. As I mounted the carb the pin was pushed back in where it should be. In all the videos and photos I've seen that pin is inside the thermowax body. I don't know exactly how that mechanism works but I'm guessing that as the thermowax heats up from the engine it pushes that pin out and into the choke, causing the idle speed to fall. If my pin is already pushed out then it seems that would only affect performance during start up.
Is it possible that the thermowax is faulty and is somehow keeping the idle speed high as if the engine were still heating up? It's idling at about 2900 rpm.
Is it possible that the thermowax is faulty and is somehow keeping the idle speed high as if the engine were still heating up? It's idling at about 2900 rpm.
