Tony,
Questions/clarification
:
Are you saying you need to
tap a thread into the hole and then fit a threaded plug? I presume you would have to use some red silicone sealant to provide a gas/watertight seal.
How long is the 3/4 UNC allen plug? 1/4"? Is it a standard length.
I have this task ahead of me in the next few weeks. My engine is 'resting' on the garage floor now.....
Ian