So it’s been sitting with the cap off for a few weeks unbeknownst to me. There seems to be a good bit of sand around the opening so I assume some inside. Any tips on how best to approach this? Thanks in advance.

 

Been driven?
First job would be to pull the pan and have a look. If no real settled debris, screen and service would be in order..
The screen will stop fine trash/particles as long as the case, hardware hasn't been exposed to suspended abrasives..

 

It has not been driven. I think this is the answer I needed to hear.Thank you