dismantel head from the block and have both pressure tested seprately
how u know the block is really cracked
oil leak
A cracked "engine housing" probably means a cracked block. Very not good. A new engine will most likely be required to fix the problem, as a cracked block is next to impossible to repair.
Check your oil, if it looks abnormal, like chocolate milk, that means there is water in the oil, your head is cracked.
You can drive a car with a cracked engine block, but it will eventually stop running. The engine will go out completely after time.
leaks
If your referring to the engine block, the motor has to be replaced. If your refering to a cracked head, the head has to be replaced. Contact a service technician you can trust. a cracked block cannot be repaired. The only option is to replace the engine.
Engine will possibly overheat, coolant will mix with the oil, and eventually destroy the engine. You must replace a cracked head gasket.
The valve cover on a typical engine is a non wearing part. If it were damaged it could be bent, warped or cracked and could be the source of an engine oil leak.
Junk in most cases.
No
You replace the engine.