HRX2174HYA Surges While Under No Load

[Jenebo]

My mower will run fine while the blades are engaged, but when the bail is released and the blades stop, the engine will sit there and surge. I have used fresh gas and used a little seafoam, but since the engine runs fine when the blade is engaged, it just seems to me that this is not a fuel issue. Also this only does it when the engine is warm. For example, when the engine is first started, it runs fine. Once I mow a little bit and stop to empty the first bag, it will surge.

 

[bertsmobile1]

the idle jet is obstructed

 

[slomo]

and used a little seafoam

So that is not working for you.

I would dump and clean out the fuel tank. Install new fuel lines and filter. Boil clean the carb.

As Bert said, idle circuit clogged . So low load surges, blade on, high load is fine. Blade on, the engine is on the main jet.