Have had this 94 accord lx for couple years now. recently the valves started making alot of noise and they seem to be clicking very loud. when i acclerate, i can hear them inside the car. i work at a Autozone and when i showed it to my manager, he said there wasn't enough oil pressure to the head. The car has about 89k miles and i saw that few weeks ago, the coolant was leaking around the oil pan area so the timing belt and water pump needs to be changed. And also a oil is leaking under the car and side of the engine. how hard is it to change those two? can the timing belt/waterpump cause the low oil pressure? would i be better off selling the car or replacing new belt/pump and maybe swap a new cyclinder head because of the loud clicking? how hard would it be to change the head? any help would be appreciated.