Originally Posted By: dnewton3
My apologies. Yes, I meant the leaf spring in Jim's picture.
The goal of the spring is to apply pressure to the media element to seal the filter, right? But excess pressure could put too much force on the media, and "crush" is towards the base end, no?
Originally Posted By: Jim Allen
With a metal core and endcaps (and there is no sign of crushing) could the media in my case even be crushed that way?
That was going to be my comment too. The metal center core butts up against both metal end caps, so it's virtually impossible to crush the assembly unless there was some crazy force put on it.
Originally Posted By: dnewton3
And, I would note that the crush factor could probably be an issue in either a spin-on (such as Jim's) or in a cartridge (such as friendly_jaceK). One happens at the factory in assembly; one happens in the garage upon installation. But they both would be a result of the media not fitting in the intended range they were intended to occupy, per the manufacturing print. IOW - some amount of force is desireable; too much is not. Several issues might contribute:
1) media element too long for designed space
2) containment component too short for designed space
3) spring force too great
- material spec'd correctly?
- material made correctly?
- material formed incorrectly?
^ +1 ^ ... My "theory" on why some Purolator filters have wavy pleats is that the length of the media material is a bit too long to fit properly between the end caps, and that along with use, the media might swell some and make the pleats squirm when they grow a bit in length.
I vagely recall seeing photos of new Purolator filters cut open that even had slightly wavy pleats. This would confirm that the pleats are too long to start with, and could explain why some models have wavy pleats and others don't (ie, Purolator has a dimensional issue on some of their filter assemblies).
My apologies. Yes, I meant the leaf spring in Jim's picture.
The goal of the spring is to apply pressure to the media element to seal the filter, right? But excess pressure could put too much force on the media, and "crush" is towards the base end, no?
Originally Posted By: Jim Allen
With a metal core and endcaps (and there is no sign of crushing) could the media in my case even be crushed that way?
That was going to be my comment too. The metal center core butts up against both metal end caps, so it's virtually impossible to crush the assembly unless there was some crazy force put on it.
Originally Posted By: dnewton3
And, I would note that the crush factor could probably be an issue in either a spin-on (such as Jim's) or in a cartridge (such as friendly_jaceK). One happens at the factory in assembly; one happens in the garage upon installation. But they both would be a result of the media not fitting in the intended range they were intended to occupy, per the manufacturing print. IOW - some amount of force is desireable; too much is not. Several issues might contribute:
1) media element too long for designed space
2) containment component too short for designed space
3) spring force too great
- material spec'd correctly?
- material made correctly?
- material formed incorrectly?
^ +1 ^ ... My "theory" on why some Purolator filters have wavy pleats is that the length of the media material is a bit too long to fit properly between the end caps, and that along with use, the media might swell some and make the pleats squirm when they grow a bit in length.
I vagely recall seeing photos of new Purolator filters cut open that even had slightly wavy pleats. This would confirm that the pleats are too long to start with, and could explain why some models have wavy pleats and others don't (ie, Purolator has a dimensional issue on some of their filter assemblies).
