Frost Plug Removal

[defdes]

Do the 1 5/8" freeze plugs on the 251 block pivot out, i.e hit on the bottom with a drift so the top spins out towards you to pull out OR drill and pull with a slide hammer?I tried the first method and got nothing.

[CSCameron]

I don't know if the 251 plugs are different from the 230 plugs? On my 230, I just drilled a hole and popped them out with a screw driver.

[Cheyenne Dave]

"Freeze Plug" is actually a misnomer. These plugs are only to close holes needed for the casting process. If we are talking about the dome-shaped welch plugs in the block, they are easiest remove by taking a 3/8" drift punch and a hammer and denting the the plug inward at its center. After several blows the plug will shrink enough to remove it with a magnate.

You should never try to hammer these plugs anywhere around the outer edge, as there is a ledge in the casting that can crack out and cause serious damage to the block. Once you get the first welch plug out, this will make immediate sense to you!

Installing new plugs uses much the same technique as removal. I use a little silicone or aircraft gasket sealant (that black, tar-like stuff) around the outer edge of the cast ledge in the hole before placing the plug. Tapping at the center of the plug expands its edges outward, making a nice tight seal. Over drive it and you will go past expanding the plug and start to shrink it again.

Good luck!

cd

[defdes]

Ahhh, very good. Thank you for the clarification....of which I need many!

[Cheyenne Dave]

Fear not! I didn't know the nomenclature before Gordon set me on course, many years ago. We learn most everything from someone else, then build upon that.

cd