FILTER change poll...run em' twice???

[Stan]

One way to know for sure is to measure the pressure before and after the filter to determine restriction. For a given install there would be a safe range. I betcha that many filters can *easily* go 2-3 oil changes and still be going strong.

If you run a drain valve you can dump and fill your oil extremely fast with no tools or mess and just run the filter longer. If you run a thermostat equipped oil cooler you better flush the lines or at least get the oil hot enough to circulate that semi-trapped fluid.

If you are worried about leaving old oil in the engine…guess what, you already do that now. Especially in oil cooler equipped vehicles.

If you really want to get old oil out do a change, filter swap and then another complete change after a few minutes of running the first-changed oil. Drop the pan, pull the valve cover and clean it up. Or use one of those powerflush rigs where they hook up hoses to the engine.

 

[Gary Allan]

Quote:
One way to know for sure is to measure the pressure before and after the filter to determine restriction.

By geeaea at 2007-11-20

 

[saaboc]

For those of us w/OF's situated more or less vertically, there is some benefit to removing the filter for more complete draining. I've found that even after sitting upside down for an extended period of time, my OF's are reluctant to drain out. However, by laying the thing on it's side, I'll find a new pool of oil inside ready to pour out. This can be repeated several times. Kind of like a magician's "never empty cup". I guess there's a small resivour of oil in a cavity at the bottom of the filter canister & gravity is able to pull it out thru the pleats when the OF is tipped over.

If your OF sits horizontally & it's possible to position a catch pan beneath it, you're all set. Otherwise I don't think most people have the time or patience for the "vertical drain" ritual. Nor do I see a great need for troubling oneself extracting a few extra tablespoons of oil when the engine will always retain a good half qt (or more...sometimes a LOT more) after draining. I just thought it was interesting trivia.

 

[labman]

When I change oil, the filter goes.

I find the sideways thing interesting. I have had very poor luck draining with the thread down. It worries me that the media is clogged and not letting the oil out of the shell.

 

[saaboc]

Good idea! I wonder what an acceptable range would be fore/aft. I'd love to mass produce something like that for the aftermarket. Seems simple enough to do I guess. What an easy thing to incorporate into new vehicles! The onboard computer could monitor the difference & simply flash a "replace oil filter" warning lamp when a pre-determined threshold was breached. Probably only $8 for two sensors...makes you wonder. One of us should call Tom & Ray Magliozzi to see what they say about this. They've got a big audience.

I've got dual thermostatically regulated oil coolers (custom DIY job & pretty trick). Every OC there's .5qt (forget if that's each or both, it's been awhile) sitting in them + whatever is hiding in the motor. Oh well.

I've seen those drain valves before & have been tempted. Though I'd be afraid to have such an easy means by which ANYONE could drain my oil, even if the valve is otherwise fail safe (unlikely). The convenience must be nice however.

 

[Kaboomba]

THis is a really tricky proposition because there are so many variables involved in every vehicle and operating conditions. That's why I suggest getting real familiar with what your regular oil pressure gage reads, and using that to know when to change.

K