jwales wrote:I had an HRR2164, rear wheel drive with what sounds like some of the same symtoms. In my case the woodruff keys (yes both were missing). Had to remove the gears to replace keys.
With the mower not running and drive axel elevated. 1.You should be able to turn the axel by hand. 2.With the traction drive bar engaged you should not be able to turn the axel. 3. Take the drive wheels off, individually turn the gear drive in the COUNTER clockwise direction. You should hear a clicking noise (the woodruff key interacting with the gear). If not the woodruff key could be missing or out of place and/or the gear could be on backwards.
On this mower's drive it has a different clutching setup than HHR2164. Below is a picture of the left hand and the right hand clutches


Apart from these then shifter needs checking ti make it is fully engaging high or low speeds, There several pins that could have broken and then of course there could be internal problems.
Dave, here is a link to the IPLs in case you haven't found one,
http://www.jackssmallengines.com/Jacks-Parts-Lookup/Model-Diagram-List/honda/4284
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