Freeze plug installation

[Sam Moore #21210]

I plan to renew the freeze plugs in my 49. They are starting to seep from corrosion. I purchased a set of old style brass (disc type, rather than cup) plugs from NAPA. They are convex and I understand that they must be struck in the center to expand them. I expect that the old-time mechanics developed a feel for seating them securely. Does anyone have any suggestions? Also, is it advisable to use a sealant such as red Loctite?

[John Washburn]

Sam,

I am not expert, but I have replaced these core plugs on a few of my Cadillacs including the 49. I also use the brass core plugs. I also suggest finding the rubber core plugs, that are smaller in diameter, to carry along just in case one fails. These fit in the hole so are not the same size as the core plugs.

I just make sure that the surface is clean and if there is a lot of rust on the surface add some good sealant, not much, just enought to fill the areas that are pitted. Then smack the old beauties in the center using a good sized punch.

John Washburn
CLC #1067
Elizabeth, Snowy Colorado

[Paul W Allen CLC#20193]

Sam,

I replaced a couple of them on my 53 a while back. I used the brass disc type. The cup type are NOT used on the 331 Engines. John is correct on the installation. I used a little permatex around the edge, then used a small ball peen hammer. A few light taps and its done. Of course, make sure the convex side of the disc is facing the outside. Good luck with it!

Paul
53 Coupe
Twin Turbine

[Sam Moore #21210]

Thanks to all for the advice.