I read that many of you are using the M1-302 oil filter. I was thinking of using it on my 575SCI but was concerned about the drain back since the filter mounts upside down. I see many are using it on the 500EFI but I don't know it it mounts upside down also.

500EFI has an upside down filter mount as well.

I could be wrong but I think that pretty much all oil filters have the drainback valve.

Roby

O.k. Thanks. I just assumed some did and some didn't since my OEM Merc seems to always drain after setting and the dipstick reads overfilled until I run the motor. This has always seemed confusing for determining proper oil level and not the best for initial engine start.


On further research I found this information from an Oil filter study.

The construction of the anti-drainback and bypass valves is an important feature. Many are made of nitrile rubber. As long as they have good sealing surfaces, they generally work fine. However, nitrile rubber diaphrams gets stiff in extreme cold and may fail to seal in those conditions. Silicone rubber seals or steel valves are not prone to this. Many bypass valves are spring-loaded steel and work well. Some are spring-loaded plastic and are often not molded well enough to make a decent seal, allowing oil to leak passed them.

Link to Study

http://www.minimopar.net/oilfilterstudy.html

so why don't we call mobil 1 and get the straight scoop on this issue?

Average Retail Price $10
Cartridge Length 4.250 inches
Cartridge Outside Diameter 3.250 inches
Cartridge Inside Diameter 1.625 inches
Cartridge Pleats 52
Cartridge End Cap Type Stamped-steel, with bypass valve
Anti-Drainback Valve Type Nitrile rubber diaphragm
Bypass Valve Type Spring-loaded steel, nitrile seal
Element Type Synthetic media, glued seam
Element Length 85 inches
Element Width 4.125 inches
Element Surface Area 351 square inches
Shell Thickness 0.022 inches
Backplate Thickness 0.138 inches
Gasket Type Nitrile rubber



Taken from the filter site