These cylinder liners have a Nikasil coating, very thin from the factory. It is a very hard surface finish, once it is worn away, the liner either needs replaced or bored and re-coated. Honing must be done with a diamond honing head.
Oh.... If you leave it for a future repair can it get worse fast? IE is it a priority to fix as soon as possible? Does the 348 have the same coating?
If I don't fix it soon I could have a catastrophic failure whereby greater damage to the engine could happen. It is just a matter of time. Nobody can predict when. Don't know about the 348.
The wear certainly gets worse fast. I would consider it a priority fix, because it's not going to get any better, and you're going to running on 7 cylinders due to lost compression and plug fouling. 348's have the same coating.
