Engine Freeze-out (core or freeze) plugs

These dents are present in the mass (body) of liquid-cooled internal combustion engines. They are called by many names, and they are metal denticles with the engine’s mass and head. The reason for the holes in these cylinders is the result of the process of plumbing (casting) to the engine body. During the manufacturing process of the cylinder block and cylinder head, the metal of the block or the head is poured into special molds, and to make internal cavities in the cast part as coolant lanes, etc., this requires making cylindrical shapes with sand with the dimensions of those lanes. After pouring the metal of the cylinder block into the mold and letting it cool, that sand is disposed of through holes in the body of the cylinder block, and the void remains the component of the corridors through which the coolant flows.
These holes are not closed permanently after the completion of the pouring stages, but they are closed by means of dents in the form of discs or plates that are inserted into these openings by means of pressing, which are called cylinders to protect the engine body from freezing. Their purpose is to protect the engine body and head from cracking in the event that the coolant freezes in these passages as a result of external weather conditions.

 
Usually the coolant freezes at temperatures much lower than atmospheric conditions, about -40 degrees Celsius, due to the chemical additives added to it. However, in some different circumstances, the coolant freezes at temperatures close to zero degrees Celsius, (in case the coolant is mixed with a high percentage of water, or water is used instead of the coolant, or its use has become obsolete in the system), in case the coolant freezes, these plates push out under pressure The fluid expands in the coolant passages, allowing fluid to exit the engine through these openings and reducing pressure that could cause the engine block to crack.
This Tabat may be damaged over time and lead Tabat damage as a result of rust or  rust electric   galvanic action (where different metal Tabat leads from metal body or head to the engine accelerates rust process) to failure in the performance of the task entrusted to Tabat when it freezes coolant.
Also, rust may cause damage to the lining of the cylinders or wear them, leading to the leakage of coolant outside in normal conditions, which requires the owner of the car to supply the radiator with coolant frequently, and failure to do so may lead to a lack of coolant, overheating of the engine, and serious problems for the engine. .
The coolant in addition to the additives that reduce the freezing point, it also contains a rust inhibitor to prevent this from happening to the parts of the cooling circuit, including the plates, but that chemical anti-rust in the coolant loses its effect after about 3 years, so the coolant needs to be changed regularly Periodic and regular.
Changing the drums (which are usually 3 or 4 on each side, and in some engines there may be drums in the back of the engine and also in the head) this may be an easy or very complicated process, depending on the position of the drums in the engine body and accessibility.
There are several points to remember when dealing with these medicines:

• Before you replace these pods, do a research to find out the actual number of pods in the engine and their locations.
• In the event that you need to replace one of these medicines, it is recommended to replace all of them.
• In the case of packing the engine, the drums must be changed as well.
• When replacing the chucks, use chucks of a metal suitable for the metal of the motor to avoid electrical rust. For this, we find that most alternative medicines are often made of copper metal.
• Always use coolant instead of regular water in the cooling system, as the coolant contains additives that, in addition to raising the boiling point, reduce the freezing point and prevent rust.