None of my T spark plugs thread all the way down into the head. There lacking a 1/4" from being all the way down. There tight. Is this normal?
Or do I need to run a tap thru the holes...What size tap?
Thanks
They have a half-inch pipe thread, wider at the top. They should go in only until they're tight. That's why they don't use washers like modern plugs.
Big Thanks!