AirCavHokie-- On my car with 38,000 miles, I change the oil & filter every 7500 miles (except for track day interruptions) but at each 2500 miles between, I change just the oil with this:
Amazon.com: Mityvac 7300 PneumatiVac Air-Operated Fluid Evacuator: Automotive
I actually read a U.K. or German based report that said new filters are less effective than filters with a a few/couple'ish thousand miles on them. I'm not convinced this is the truth but it's a convenient suspension-of-disbelief that allows me to sleep at night while I let an oil filter live 7500 miles in my car. I've also been unable to find this article again--how convenient to my cause, huh?
My comments:
- None of the plastic tubes that comes with the unit fit with the Lotus but a simple plastic generic tube from OSH (Orchard Supply Hardware) works fine;
- When pulling the tube through the crankcase, it can nick on sharp internal corners/edges. Once a nick is made, the plastic tube is more likely to catch next time; even if it does catch, gentle wiggling should relieve it from any catches. To minimize this, I get a new tube every 4-6 oil changes--they're cheap but could be a nuisance to some;
- The extractor doesn't always pick up *all* the oil without some figgiting (see above comment), so you have to have some patience to get it all out;
- Sorta slow ±15 minutes--I let it do it's thing while I play with other stuff in the garage and come back to it every 5 minutes. I can not imagine using the manual pump version;
- The PneumatiVac version is loud. Not Arqray-Single-Tip loud but a lot of air whistling sound if you're sensitive (which considering the nature of this forum, you're probably not).
Overall, it's a nice solution to a problem few have.
And no, I don't use a flowbee to cut my hair. rotfl