Hour meter goes blank in the rain?

[The motor guy]

I have 2 of these enm hour meters that wrap around the spark plug and they both go blank and come back on a few days later. One kept track of the hours and even kept logging them with a blank screen while the other just reset. I don't get it.

 

[The motor guy]

I used to use Briggs and Stratton hour meters but the last two of those i bought are junk too.

 

[SilverFusion2010]

Moisture intrusion shorting out the screen would be my guess

 

[The motor guy]

Anyone use those hardline hour meters?

 

[Superflan]

I use the cheapest hourmeter + rpm available on Ebay