It all depends on when you check it. When the vehicle is hot, and cooling system is under pressure, it should be firm. When it is cool, or the pressure has been let off, it may be soft. It should not be abnormally bulging at connection ends, or make a crunch noise when you squeeze it, or have noticeable soft spots. This would indicate the inside lining is breaking down.
Saturday, June 5th, 2010 AT 4:02 PM