The MANWAY8 does two jobs with one opening: it is an 8 inch threaded manway with a built-in 4 inch breather. The lid gives you hand-and-forearm access for cleaning and inspection; the breather keeps the tank vented while the lid stays sealed. On a tank that fills and drains fast, that venting is not a convenience - it is what stops walls flexing as the air column tries to keep up with the liquid.
Combining the functions saves a penetration. Every hole in a tank is a place to seal, a place to leak, and a claim on the limited flat real estate of the top face; a manway that carries its own vent leaves the rest of the surface free for fills and senders. The 8 inch bore itself passes a brush, a hose, and most float assemblies - the everyday service work.
It is matched to Ronco's own moldings, from the same Tustin, California plant that has produced them since 1974. Tanks that benefit most - working holding and transfer moldings - are in our RV holding tank and boat tank categories; the full line is on the Ronco Plastics hub. OneSource Plastics is an authorized Ronco Plastics dealer.
