type of frost plugs used

[51HenryJs]

I changed my frost plugs which are the cupped (?) type and they started to pop out and I was told I put them in backwards, convex in towards the block. Any advice/ pictures would be of help. I have rubber expansion plugs in now.

[Vagabond Russ]

The bulge goes out.  Using a large 3/4" flat aluminum bar, tap the bulge in and the freeze plug will expand and stay in.  I use some #2 sealer on the hole before setting the disc.  Never had one leak.

[51HenryJs]

Thanks, lots of people have told me that. Hope it helps someone else.

[Fid]

Using a large 3/4" flat aluminum bar, tap the bulge in and the freeze plug will expand and stay in

Yes that works.

If you don't have an aluminum bar you can also take a ball-peen hammer, place the ball end against the plug and hit the other end with a another larger hammer and that too will spread it out and seal nicely.   

[pjkaiser]

I've never heard the term "Frost Plugs", so I looked it up.   Here is what I found - "Core plugs are used to fill the sand casting core holes found on water-cooled internal combustion engines. They are also commonly called frost plugs, freeze plugs, or engine block expansion plugs".   I grew up in the midwest and we called them Freeze Plugs.

What I do know is that the terms Frost and Freeze plugs are a misnomer,  They will not push out if the water freezes in the block.  The block will crack if that happens.   This might be a regional term but Core Plugs tell you what they are in the name the way most parts are named.   Just an FYI.