i have a 96 discovery se7 with about 149,xxx so a couple days ago i left home and while driving noticed a slight ticking sound that sounds similar to a manifold leak it grew louder and louder until it is so loud now my rover sounds like a lawn mower while running. my dad seems to think its a blown head gasket. i find it hard to believe because i have no coolant and oil mixing and also i am not losing coolant or burning oil....... besides his possible diagnosis i have narrowed it down to either my exhaust manifold or the head gasket. I can see deposits on the front passenger motor mount where the exhaust gases are ending up. and if i put my hand in that spot while the car is running i can feel the exhaust gases hitting my hand. now with that said i might be able to post pictures or a video to give you a better idea of what im dealing with. the truck doesnt overheat nor do i experience any power loss i have changed the oil and filter about 400 miles ago. could this really be my head or is it just a pitted manifold any ideas?