This is where a little bit of Sherlock Holmes enters mower repair.
You have a look at where the mower lives.
Had a customer who kept their mower in the same shed as the chicken food , horse food & bedding hay
Every time I came the mower was stuffed with mice
Solution was to park it outside in the breezeway where it gets a colder overnight.
Eventually they took the advice & housed a pair of homeless cats in the shed , no more mouse problem.
Amazed how many ex-city horse owners do not realize that mice can kill horses .