OutdoorKing Repair Forum Forums Repairs and Maintenance Questions on Engines Questions On Honda Engines Honda GCV160 Won't Idle

That's a good point, luvpsi, there are two different maladjustments that could cause this: the idle speed screw could be backed out, or the speed control cable could be maladjusted so that the kill switch operates with the speed control set at idle instead of across the detent, at stop. Just running through a normal tuning procedure would fix either of those faults, without dismantling anything. The mower should certainly be tuned before attacking the carburetor.

Finding out whether the idle cutting out problem is due to maladjustment of the speed control cable should be the work of a moment: just remove the spark plug, attach it to the plug lead, hold it against a bare metal part of the engine, set the speed control in the idle position, and pull the starter. If there is no spark across the spark plug gap, the kill switch is operating and the speed control cable needs to be adjusted. If there is a spark, the problem must be one of three things (in order of how easy it is to check them):
1. Idle speed screw set too low. Wind the screw halfway in or slightly more, and see if it will then "idle" (at about maximum engine speed). If it will, back off the idle speed screw and see how slowly it can run. If it runs perfectly well at the specified idle speed of 1700 RPM, the problem was just a maladjusted idle speed screw. If it dies when you try to slow it down to idle speed, consider possibilities 2 and 3.
2. Idle jet or passage obstructed by dirt. Clean the carburetor, following the method set out in detail in the previous thread referenced above. As part of the same exercise, check for intake leaks at the carburetor insulator gaskets. If you do this job properly and the problem still exists, we are left with the least likely, and most inconvenient, possibility.
3. Internal engine problem. We can discuss this if necessary, after eliminating possibilities 1 & 2. The first question I will ask, is whether the engine still develops full power when mowing with the speed control set to High.