MTD/Lowes 42/14 grass cutting issue

[rgardeck]

Just picked up a Lowes/MTD 42/14 riding mower from my uncle.
Something strange occurs when mowing my lawn.
Some spots are higher than others because of sunshine and rain exposure.
When mowing the higher spots, I noticed the left blade will just stop spinning and the grass isnt cut.
The right blade keeps spinning and cuts fine during this time.
Both blades spin fine on lower spots of the yard which is the majority of my cutting area.
What could be causing the left blade to stop spinning in high spots? It starts spinning again once i get into a lower grass-height area.

 

[Rivets]

Check the belt tension on the left spindle. Also, remove the belt and check the spinle assembly, making sure that it is running smooth and true. If the bearings are out your belt tension will change and the blade may stop.

 

[Bob E]

worn or improperly tensioned belt, stripped spindle/pully, loose nut.

-edit- rivets beat me to it :smile: -

 

[SeniorCitizen]

You should be smelling a burning belt

 

[Jack17]

I'd have to say that the bolt or a nut that holds cutting blade against the spindle might be a little lose.