- Joined
- Jun 2, 2002
- Messages
- 4,341
Was at "THE MART" yesterday browsing oil filters. I needed a filter for an old Ford Focus and the Fram application was a PH8316. There were two on the shelf, both with damaged boxes, and with differing labels. Other than the part number, they did not look alike.
I took both filters out of their boxes to check them out and one of them had what appeared to be a by-pass valve very close to the baseplate. The other filter had a by-pass valve in the usual location near the closed end of the can. I had never seen a filter like this and thought it was possibly a faulty assembly. I was curious how the oil would get past the filter since no filtering media was visible.
I poked out a message to Fram on the internet with my pictures and drawings and graphs and VIN numbers for application, etc., and Fram got back to me with this neat picture. They say they no longer produce the PH8316 with this design but I thought it was interesting enough to share on this forum.
The filter is designed to use the membrane anti-drainback valve to keep the pre-filtered oil in the filter and the "antidrain-valve engine" is to keep the post-filtered oil in the filter. After thinking about it I think it's pretty nifty. Obviously the design was changed for expense and complexity reasons but it was something nice to learn. I bought the filter that did NOT have the double anti-drainback valve because I thought it was faulty. I may go back and get it just to put in my oil filter museum.
Photo attached:
I took both filters out of their boxes to check them out and one of them had what appeared to be a by-pass valve very close to the baseplate. The other filter had a by-pass valve in the usual location near the closed end of the can. I had never seen a filter like this and thought it was possibly a faulty assembly. I was curious how the oil would get past the filter since no filtering media was visible.
I poked out a message to Fram on the internet with my pictures and drawings and graphs and VIN numbers for application, etc., and Fram got back to me with this neat picture. They say they no longer produce the PH8316 with this design but I thought it was interesting enough to share on this forum.
The filter is designed to use the membrane anti-drainback valve to keep the pre-filtered oil in the filter and the "antidrain-valve engine" is to keep the post-filtered oil in the filter. After thinking about it I think it's pretty nifty. Obviously the design was changed for expense and complexity reasons but it was something nice to learn. I bought the filter that did NOT have the double anti-drainback valve because I thought it was faulty. I may go back and get it just to put in my oil filter museum.
Photo attached: