itt már megírtam mi az én rutinom...
az elmúlt 15-20 év távlatából alapvetően működik, de...
a gumi alkatrészek öregedésével nem fogsz tudni mit tenni...
"...When you switch off the engine, some of the valves are kept open.
Or, if you just keep running the engine at idle rpm without driving or repeat the multiple short distance journeys,
you are circulating the moisture/fuel rich blowby gas inside the engine.
Once the engine cools down and temperature drops, it will create condensation inside the engine.
Not a problem if you drive regularly.
However, if you park the car for months, it may allow the build-up of rust at certain places.
Next time when you crank the engine, the rust may cause scratch markings.
It won’t cause immediate issue but if this process was repeated many times over the years,
it shall cause bite markings.
It's different from oil film issue caused by oil pressure drop.
With oil film issue, you will see lots and lots of scratch line markings at entire width of the area if it's metal-on-metal contact.
And if the temperature got too high, you will see changes in colour or even the melted materials.
With the rust issue, the markings are more like the material being chewed off and spot like shape instead of full width.
Fortunately, over the years/miles after this happened, the edge of the chewed off section was smoothed out with no wear to the cam lobe surface.
Considering the cam rotation direction, the width of cam lobe and no further contact between the dimple and the cam lobe,
the rocker arms can be re-used.
This can happen at the crankshaft journal/main/rod metal area and the damages would be even more serious than the rocker arm section...."