Originally Posted by Paul_Siu
I was watching this video of some youtuber who suggest that we should considered replacing the radiator cap, thermostat, and water pump at some interval. He was suggesting that may be every 60K the radiator cap and thermostat should be replaced. The radiator cap because the seal breaks down and it no longer holds the pressure it used to. The thermostat may eventually failed. The water pump should be replace when you change timing belt.
I do recall that in my first car, my thermostat seems to fail often resulting in overheat of the car and probably contributed to its demise. In the past, I always replace the water pump every timing belt change, but the Subaru dealer suggested that it wasn't really necessary since the water pump is quite robust. What do you think?
Paul
Not so much vehicle specific but in reality a car is no different than any other machine in terms of your question.
Assuming a properly assembled part ( whatever it is) and properly matched function ( part specifications are within range of the actual application it has to function in regardless of the parent machine) then there is no legitimate "engineering" answer to this.
Boiled down there are 2 basic reasons for this.
Since the parts are different in construction, design and purpose ( and often exposed to different areas of a machine which means the exposed stresses are different as well)- their "wear" cant be correlated in any legitimate manner.
Then is the scale to determine the frequency.. In reality most scales ( hour meter, odometer etc.) are measuring a frequency which is seldom directly relative to the stressors that contribute to the degradation of the component. ( more of a scheduling tool rather than an indicator of loss of performance)
It boils down to risk ( actual, perceived or set value) the individual sets for his equipment based on his circumstances on what level is acceptable.
Then that risk is qualified as to the skills, level of maintenance and so forth that specific individual has or is willing to invest in.
Its really in the eye of the beholder.
Personally when I repair something ( mine or client machinery) I always propose at a minimum to inspect/repair the entire function ( or system) to the proper level because I have often found that introducing a "new' part in a uniformly worn system will often become the failure mechanism for the next weakest link.