Thank you to those who’ve responded to my question about how to know when an oil filter contacts the housing base. Checking for wobble is a good idea. I’d never thought of doing that.
To allay any worries, I’ve been changing oil on our family vehicles for almost 50 years and haven’t had an oil filter come loose yet. Knock on wood!
But to quote an old saying, “It isn’t the things you don’t know that get you in trouble, it’s the things you know for sure that just aren’t so.”
One question: Do you tighten the filter slightly, back it off to loose, and then start over. I do. The reason I ask is: what would happen if the gasket hasn’t been fully pressed home? You’d press the gasket home during the ½ - ¾ turn, but the filter might still be very loose. That might explain the occasional loose filter.
How do you know you know when the filter contacts the housing? You may have been installing oil filters for years but you never get any feedback. Too tight, too loose, how would you know? If a filter is too loose you’ll likely hear about it. But too tight and your customers may curse you but you’ll never know.
If we ever have a BITOG get together I suggest we set up an apparatus to test each of our abilities to tell when an oil filter touches the base of the housing. It would be set up so the candidate can’t see, and ideally in the "usual awkward position". We would know the correct position and measure everyone’s ability to tell when the filter touches the housing, measured in degrees. That would give us the group’s variability. And we would have everyone do it 3 times over the course of the day. That would give us each individual’s personal variability. We’d give each participant feedback on how he or she did (how far from correct, and how much variation). The winner (3 answers closest to the correct answer) would win a case of cool beverages, ideally to share.
My bet is there will be a spread of at least 30 degrees for the group, and maybe even 90 degrees (a full quarter turn). And an individual’s typical variability will be about the same. What if it’s more?