Its no secret that Subaru of America and American Honda with corporate blessing have their own line of OEM marked oil filters, made by /Honeywell Fram in the US. But every car that comes into the country has a Japanese made Subaru filter and I assume every Honda that is imported comes with a Honda of Japan filter. You can buy both flavors in the US on ebay and the Japan filters use less cardboard and more steel.
So out of curiosity, I took off my dealer installed American Honda filter on my 2004 CRV and changed the oil after 3,200 miles....the oil was used but not bad looking and was a year old. The car is used as a winter car and a backup. I then cut open the Fram and as you would expect, used oil came out but boy was it BLACK. so I want to make sure I understand how a filter is supposed to work.
IMHO, oil comes in the little holes and pushes past the anti drain back valve (the orange rubber) and passes through the cardboard pleats and out to the engine through the center hole. If the filter would become clogged, or it is just cold, the oil would push open the bypass valve (left) and get to the engine without going through the filter. IIRC some engines also have a bypass valve in the block. So how do you explain coal black oil trapped in the filter?

So out of curiosity, I took off my dealer installed American Honda filter on my 2004 CRV and changed the oil after 3,200 miles....the oil was used but not bad looking and was a year old. The car is used as a winter car and a backup. I then cut open the Fram and as you would expect, used oil came out but boy was it BLACK. so I want to make sure I understand how a filter is supposed to work.
IMHO, oil comes in the little holes and pushes past the anti drain back valve (the orange rubber) and passes through the cardboard pleats and out to the engine through the center hole. If the filter would become clogged, or it is just cold, the oil would push open the bypass valve (left) and get to the engine without going through the filter. IIRC some engines also have a bypass valve in the block. So how do you explain coal black oil trapped in the filter?
