ACS model A-600 reservoir

Did you guys replace the red plastic cap or keep it?


http://www.aircraftspruce.com/catalog/lgpages/a600reservoir.php

I've kept it so far

I don't see a compelling reason to change it. It does have a pin hole for a vent - if you plan to stay upside down for any period of time, you might want to do something different. Otherwise, it keeps the dust out, keeps the red stuff in.