Freeze plugs

[66furys]

Learning at my age is somewhat painful. I have recently seen some posts on head questions, and some on the blocks, and noted that the freeze plugs appeared to be installed upside down. I have replaced many over the decades I have toyed. But, in my experience, the freeze plug is a tight fit in the hole, with a ledge to seat the cup edge. Then, you use some flat wide punch to hit the convex dish. This then further tightens the plug. Sealers optional. I do not get the inverted plug installs I have seen of late.....and if you hit the center, it would tend to loosen it. Just interested in the rationale here.....I guess mother mopar had an idea to make the threads left handed.

 

[CBODY67]

On the earlier style, you did hit the center to tighten the plug. On the "cup plug" style, you use some Permatex #2 as the "lube", around the "lips" of the plug, insert the deep part in the hole, and then use a socket that just fits inside the cup, to aim and tap the plug in squarely, until it is fully seated. Just deep enough that all of the lip edges are just inside of being flush with the outer part of the casting. Noting how deep the existing plug is as a guide.

Enjoy!
CBODY67

 

[66furys]

Now you have me scratching something. Was the early plug just a concave disc, not cup style.....hmmm, cant recall.

 

[CBODY67]

Not sure what "early" means, but I've been seeing cup plugs since at least the earlier 1960s.
That is what came in the 1966 engines, from the factory.

 

[66furys]

I replaced them in my first 53 mopar 6 and more recently in an MGB engine also rebuilt....but have forgotten most of what I learned earlier. After a study on the Utube, I agree that most seem to be this inverted cup, not as I recalled. And, I found this install with the flat type that get mashed to tighten....... But, I give....this cup type is the normal type install and is not what I had recalled....just press em in with some sealant. Got it.