Other potential causes of a ticking noise from that area include:
* Lifters (Hydraulic or Flat Tappet): These are far more common culprits for ticking noises. Worn, collapsed, or sticking lifters are a frequent cause.
* Pushrods: Bent or worn pushrods can also create ticking sounds.
* Valve train components: Although less likely, there could be issues with the valves themselves or other components in the valve train.
* Exhaust manifold leak: While unlikely to be the source of a *slight* ticking, a small leak near the valve cover could make a ticking-type sound.
Diagnosing the Problem:
Because several things can cause this, a proper diagnosis requires more than just listening. A mechanic would likely:
1. Inspect the valve cover: Look for anything obvious, such as loose hardware or external damage.
2. Listen more closely: Try to pinpoint the exact location of the tick. Does it change with engine speed?
3. Check the pushrods: If possible, visually inspect the pushrods for bends or damage.
4. Check the rocker arms: Inspect the rocker arms for excessive wear or looseness.
5. Perform a compression test: A compression test can help rule out valve problems.
6. Possibly use a stethoscope: A mechanic's stethoscope can help isolate the precise source of the noise.
In short: While bad rocker arms are *possible*, they are not the most likely cause of a ticking noise in a 318 Magnum. A professional inspection is needed to determine the actual source of the noise. Ignoring it could lead to more serious engine damage.
