Problems with my 2000 Hyundai Elantra

I am not sure how they came to the conclusion that you have a cracked valve and if the engine is not disassembled.

Water getting to the oil are either due to a bad cylinder head gasket, cracked cylinder head or engine block/liners.

If the engine had overheated previously, the bad head gasket would not be surprising.

Depending on the actual fault of the noise and damage, it should be repairable but economically it could be expensive so you need to find out the actual cause and what needs to be replaced for repairs versus considering an engine replacement.

You're welcome. We try to help as much as we can but due to overhelming questions coming in, there is no guarantee that your questions would be answered, it could be missed or if the amount of information is insufficient, it sometimes is not easy for us to undrstand the problem and provide an answer.

When engine overheats, it can cause latent damage to the cylinder head gaskets and the fault would only surface after some time, ranging from days to months.

Symptoms indicates a bad head gasket and that is what you should be diagnosing. Cost of repair would depend on what needs to be done.

Glad to be of help.

Have a nice day.