Valves

Question, Since ive had my car ive noticed my valves are chattering a little louder than usual (knowing that my clutch fan isnt working properly and electric fan mod is in the works...) i was wondering if the lack of engine cooling could be the issue?, how to fix the problem? is it normal?, or its time to replace them? and if so how hard or expensive can it be......(engine has 159k mi running 9psi boost no intercooler yet) other minor have been done also, can somebody please help? (sorry for all the questions just wanna be sure :| )

Sure it's not your injectors pulsating? If your sure it's your valves, then you might want to try adjusting them first to see if that takes care of it before replacing them.

Mechanical valves do make more noise than hydrolic lifters. It is possible that they just seem louder because the fan isn't over powering them. However it would be a good idea to check the oil, just to be doubly sure. Ok, so you have about 254,000 km's on the car, so it it possible that a top end rebuild may be in order...First things first I would check the oil level, and if it is need of replacement do that too...Once you see the oil, I would go from there...8)

Mechanical valves need to be adjusted periodically. As they get a bit slack, they will start chattering.

But again, running low on oil will do the same.

If your oil level is up to where it should be, pull the valvecover and reset the lash.

How do you adjust the valves on a CA18ET top? (or on any car)
I have never tried to adjust them before, and one of my two CA18ET´s has "valve clapper".