Rain Bird 100-DV Flow Control Stem Leaking: O-Ring Replacement

A user added a soaker hose to a drip zone and needed more pressure. Opening the flow control on their Rain Bird 100-DV valve caused water to spray from the threads of the flow control stem. The filter was already clean.

Pinpointing the Leak

The follow-up clarified: "Leak is coming from the threads of the flow control valve - the small stem on top of the 100-DV. Turned all the way to the right (clockwise) - no leak. Turned to the left (counterclockwise) - water starts to spray from the threads after 1/16 of a turn."

Diagnosis and Fix

Matt identifies the cause: "My guess is the O-ring is bad and needs to be replaced." Options:

• Remove the O-ring and match it at a hardware store.
• Replace the entire valve top (bonnet assembly)—often cheaper than buying parts separately for the DV-100.

He provides a link to the Rain Bird DV-100 parts breakdown for reference.

This is a common wear point on older DV-100 valves; the flow control stem O-ring hardens over time and leaks when the stem is backed off to increase flow.