However, I have noticed that the type of coating they currently have seems to dissolve when the valves are heavily oiled with lamp oil every day. I cannot figure out why this is. Did they change the composition of this coating? I installed a new set yesterday because the old ones had zero coating on them and were clicking (due to coil bind, not because they were bent. They are like a millimeter too long for my valves.) The new springs seem to have a silicone coating rather than the old plastic one (which was prone to embrittlement and shedding).
Anyway, the reason to replace these has always been because — eventually — the coating disappears. Now it seems to completely dissolve. No fragments, no nothing. Just no more coating.
Weird…
I guess I need to have my lower caps machined a bit to open the retainer recess to better fit the diameter of the springs, and also to deepen them by a millimeter or so. This seems to be the case for these springs in *all* Nirschl-made piston sets. Perhaps the coil bind is causing the coating to fragment, which leads to tiny bits being washed away by the oil.
Hmm. More stuff to sit and ponder as I suck down heated bean juice…
