Freeze Plugs???

frost0100 · Dec 30, 2005

Picked up my new engine today - 351W - it has what my friend told me was freeze plugs - he's a chevy man so i figured i'd get the details here.

My question is this -- there are two up front 2 in the back and 1 large one in the center of the back - I think that is all. But only the large one is there.

1. Should those have come with the engine?
2. Is this something I can buy and just pop in myself?
3. are they called freeze plugs?

I was told that these will pop out and let the anti freeze out, instead of cracking my block.

rbohm · Dec 30, 2005

frost0100 said:
Picked up my new engine today - 351W - it has what my friend told me was freeze plugs - he's a chevy man so i figured i'd get the details here.

My question is this -- there are two up front 2 in the back and 1 large one in the center of the back - I think that is all. But only the large one is there.

1. Should those have come with the engine?
2. Is this something I can buy and just pop in myself?
3. are they called freeze plugs?

I was told that these will pop out and let the anti freeze out, instead of cracking my block.

the large center one in the back seals the rear cam bearing and its attendant oil galley.

1: most rebuilts have the core plugs installed.

2: you can buy core plugs and install them with no problem. i recommend that you use brass plugs with permatex #2 sealant.

3: as you may have noted they are properly called core plugs, as these openings are where the core supports are located to support the casting cores for the components being cast.

Iamdiffrnt · Dec 30, 2005

Yes They are called freeze plugs,
the big one in the back is actually to plug the back of the cam bore

The others you can pick up at any auto parts store, pretty cheap.

Make sure the holes are clean, I use permatex 2? I think (the one that dries hard).
They can be a pain to get in straight, so be careful, you don't want to drive one all the way through and into the block

And as to whether they protect the block, I wouldn't depend on it. I beleive they were primarily for removing the casting sand.

Good Luck! :SNSign:

Pathfinder65 · Dec 30, 2005

To help drive the freeze plug in straight I use a large socket, just large enough to fit inside the freeze plug and then hit it with a mallet. A lot easier than trying to hold the freeze plug itself in place and hit it, along with your fingers

mustangman1974 · Dec 31, 2005

pathfinder65 has the right idea in installing them. The ones int he side of the block were actually to save the block in freezing weather, hences the name freeze plug. water expands when its frozen. much better to crack a 2 dollar brass plug then to crack the block because the water had no where to expand to.

dennis112 · Dec 31, 2005

Don't forget to install the one at the rear of the block's lifter galley, just forward of the intake manifold-to-block sealing surface! It's approximately 1/2" to 3/4" in diameter.

Max Power · Dec 31, 2005

mustangman1974 said:
The ones int he side of the block were actually to save the block in freezing weather, hences the name freeze plug. water expands when its frozen. much better to crack a 2 dollar brass plug then to crack the block because the water had no where to expand to.

That's somewhat of a wives tale. While they are commonly called freeze plugs or expansion plugs, the primary purpose as stated above is for the casting process and for cleaning sand out when done.

Anybody with much experience with blocks that have been frozen will tell you, if these were ever designed to pop out during freezing, the design failed miserably. They are usually the last things to give.

mustangman1974 · Dec 31, 2005

doesn;t suprise me much about the viability of the freeze plugs. I live in so cal never really freezes here. I have an old "printed in 61" ford tech manual. Thats where I started learning about my mustangs. SO it was the orginal design intent, but as we all know stuff usually does not work as intended. You learn something new everyday. I had no idea they used those for cleanouts.

Freeze Plugs???

frost0100

Member

rbohm

Iamdiffrnt

Member

Pathfinder65

New Member

mustangman1974

Member

dennis112

Max Power

Active Member

mustangman1974

Member

Similar threads

Freeze Plugs???

Member

Member

New Member

Member

Active Member

Member

Similar threads

Privacy & Transparency

Privacy & Transparency