What is the purpose of a freeze plug and What is the purpose of a PVC valve?

Answer 1

Freeze Plug - The coolant in your engine can freeze if there is not enough Ethylene Glycol in the system. As water freezes, it expands. As it expands, if there is not a freeze plug the force of the ice is enough to crack the casting of the engine block. The freeze plug will be pushed out of the hole is is pressed into allowing the ice to have an avenue for expansion.

PCV Valve - Positive Crankcase Ventilation. As the engine operates, the is an amount of gases that will pass between the piston rings and escape into the crankcase. The PCV valve allows these gases to be drawn back through the intake system and be burned in the combustion chambers without contaminates being allowed to enter the crankcase.

Hope this helps ;)

Answer 2

A freeze plug is a pressure relief in the case of the engine block freezing. If the coolant within the block frrezes, it expands. Since the engine is sealed, something has to give. Replacing a $5 freeze plug is a lot cheaper than replacing a $1000 engine block.

A PCV (Positive Crankcase Ventilation) valve is a mechanism for routing the crankcase blow-by from the valve covers back to the air cleaner. During combustion, a miniscule amount of expanding gas blows by the compression rings on the pistons and ends up in the valve covers. The PCV valve releases this built up pressure, preventing its blowing a seal or head gasket. This blow-by is routed back to the air cleaner so it can be re-burned in the engine.

Answer 3

Without enough anti-freeze your radiator can freeze solid and the ice expands to crack your radiator and your engine.

The freeze-plug pops off before damage is done......hopefully.

The PVC valve takes the positive pressure gasses off of your crankcase and re-directs it back into the intake manifold where the gasses are burned again.....for cleaner exhaust as a result.

Answer 4

Both can be found at your local "adults only" parlour.