sounds like you use a bad mechanic a good mechanic would replace a cracked exhaust manifold to start with if you can smell gas,there is obvioulsy a leak in the fuel system. this needs to be found as it is a fire hazard
It must be REPLACED with another 1.
A cracked radiator can not be fixed. A cracked radiator needs to be replaced . A mechanic can replace one in a few hours.
White exhaust usually means that there is water in the combustion chamber and there is a crack somewhere. Pull out the dipstick and see if the oil is a milky white. If it is then you have either a cracked head or a cracked block. Heads cam be replaced somewhat affordable by a reputable mechanic, cracked block the engine is toast needs to be replaced.
An exhaust leak is usually the result of a bad gasket or a cracked manifold. For a proper fix, either the gasket or both the manifold and the gasket must be replaced.
leaking or cracked manifold
Intake and exhaust manifold gaskets are also replaced along with the head gasket. Head is inspected and if cracked it is replaced. Head bolts should also be replaced with new ones.
manifold or downpipe gaskets may be leaking gases or worse, cracked manifold
A cracked/warped head, Blown head gasket, cracked cylinder wall, or cracked/warped intake manifold.
A good clue would be water in the oil. That said, just because you do not have water in the oil, doesn't mean the block is not cracked. Have a good mechanic check the car.
IT depends on if IT's an INTAKE or EXHAST MANIFOLD.
if it is the intake manifold YES, exhaust manifold NO.
A cracked screen can be replaced, but it will be an expensive repair. Think $200 or so.