I realised that when trying to screw the filter back on it would hit a point and keep spinning indicating an issue with the thread. So I bought a new Ryco filter today and test fitted and and its doing the same thing.
Tried the old used filter and it screws on fine.
I notice the new Z411 has a number 20 punched into the top which my old filter doesn't and the thread hole looks slightly larger.
I'm wondering if anyone else has had a similar issue? I have a feeling there may be a bad batch of Z411s going around.
Thought it was worth giving everyone a heads up anyway.
Edited by VIN18M, 03 May 2015 - 06:54 AM.