Bill, why not remove the plug, center drill and tap it for say
1/8 NPT and install the drain cock in the plug itself?
Trying to match the threads or re-tapping the hole is more
complicated … IMO.
JWW
From: Rotary motors in
aircraft [mailto:flyrotary@lancaironline.net] On Behalf Of Bill
Bradburry
Sent: Thursday, March 19, 2009 2:28 PM
To: Rotary motors in aircraft
Subject: [FlyRotary] Renesis Water drain plug
There is a small plug on the left side of the engine
as it sits in the car, (right side in the plane) at the lower part of the
center iron. It is adjacent to the grounding plate for the ignition.
This plug will drain coolant from the engine.
Has anyone tried installing a drain cock similar to what you
would see in the bottom of a radiator in this location? Do you know what
the thread sizes are and what would be necessary to install a drain cock?
Bill B