What are freeze plugs for?

[madhat]

What exactly are the freeze plugs for?

 

[DougsfastZ]

Originally posted by madhat
What exactly are the freeze plugs for?

If, for what ever reason, the coolant in your block freezes, those plugs will pop out to release the pressure, rather then cracking the block.

Down here in Florida, it's just one more thing to check when looking for a coolant leak (usually the last).

Doug D

 

[n20junkie]

actually it has nothing to do with freezing. they gained that nick name due to the fact that they push out if the block coolant were to freeze. the correct name for them is core plugs. when the sand is formed for the block castings it is pretty stiff, and when the block is cast you have to get all that sand out of it. its pretty tough to get all that sand out of tiny head bolt holes, so those core holes are added to allow the sand to escape. then the holes are plugged, with what we now call freeze plugs. Ever notice that on most engines there are a few really big holes in the head deck for coolant, but your head gasket has a tiny hole where that big hole should be. thats becasue those big holes were also used to get the sand out of the block. the head gasket has the correct size hole in order to balance out the water flow to the heads.
Grant

 

[KEVINS]

Originally posted by n20junkie
actually it has nothing to do with freezing. they gained that nick name due to the fact that they push out if the block coolant were to freeze. the correct name for them is core plugs. when the sand is formed for the block castings it is pretty stiff, and when the block is cast you have to get all that sand out of it. its pretty tough to get all that sand out of tiny head bolt holes, so those core holes are added to allow the sand to escape. then the holes are plugged, with what we now call freeze plugs. Ever notice that on most engines there are a few really big holes in the head deck for coolant, but your head gasket has a tiny hole where that big hole should be. thats becasue those big holes were also used to get the sand out of the block. the head gasket has the correct size hole in order to balance out the water flow to the heads.
Grant

EXACTLY!

KS

 

[DougsfastZ]

Opps, learn something new everyday.

I retract my first post

Doug D

 

[TurboBuckeye]

Originally posted by n20junkie
actually it has nothing to do with freezing. they gained that nick name due to the fact that they push out if the block coolant were to freeze. the correct name for them is core plugs. when the sand is formed for the block castings it is pretty stiff, and when the block is cast you have to get all that sand out of it. its pretty tough to get all that sand out of tiny head bolt holes, so those core holes are added to allow the sand to escape. then the holes are plugged, with what we now call freeze plugs. Ever notice that on most engines there are a few really big holes in the head deck for coolant, but your head gasket has a tiny hole where that big hole should be. thats becasue those big holes were also used to get the sand out of the block. the head gasket has the correct size hole in order to balance out the water flow to the heads.
Grant

I have to explain this on a weekly basis . The worst are the guys with busted blocks who want to know why the freeze plugs didn't pop out and save their engine. ( I work in a boat shop )

 

[Turbo Indian]

Originally posted by DougsfastZ
Opps, learn something new everyday.

makes 2 of us