For us weekend warriors (OK, maybe less often then that even) who don't go through a bottle a day, how long until the solenoids tend to have problems due to inactivity? The ones in my lab at work tend to stay rather functional for months on end without use and last for years, but they are not subjected to high temps while sitting over an engine either. TIA

 

I've had the same set for years before, no problems here.

Jeffrey