Weak self-propel

[TVZ]

My Honda HRR216VXA propels itself on flat ground, but when I go uphill the wheels stop turning. I have adjusted the cable so they start turning soon after I push on the lever. Is there something else to adjust? Thank you.

 

[TVZ]

Ok, so by propping up the mower I can see that when I engage the wheels but apply pressure to them to stop them from turning, the drive shaft continues to turn but the wheels do not. Does something wear out in the wheels to cause this? Will replacing the wheels fix it? Thnx for any insights...

 

[pugaltitude]

There are pinions, ratchets and cogs inside the wheels which can wear out and stop the wheels from turning.

Time for stripdown and look.