A spin-on filter has been removed from service and it has has collapsed in on itself. Why? What has caused this condition?
The first thought might be that the filter has some type of defect that has caused this problem. This is usually not the case.
Lubrication systems are equipped with a bypass valve in either the system or within the system’s oil filter. The bypass valve opens to allow oil to go around the filter when conditions make it difficult for it to pass through the filter’s media. Cold start-ups or a filter that has not been properly serviced are two common instances to bypass the filter. The opening of the bypass valve is necessary to prevent oil starvation. An open bypass valve resulting from a cold start is usually a short-term condition because the oil temperature quickly rises. When the filter is improperly serviced, and becomes plugged, the filtering process can be negated until such time as a new filter is put into service. During this plugged condition, the bypass valve will continually open and close to allow oil to flow around the filter. If this occurs, the oil will not be properly cleaned by the filter. The collapsed filter is a clear indicator that the lubrication system is not functioning properly and that maintenance may be required.