Any harm in leaving the oil filter off and oil draining for a few days?

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Narwhal

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O-470L in a C182B.

I made a mistake and did an oil change after my last flight. I figured the usual local supply shops would be open for the biggest shopping day of the year (black friday) but they were all closed until Monday, and I don't have an oil filter. Is there any harm in letting the airplane sit for 72 hours with the oil drained and filter off until I can get a new champion oil filter? I currently have the drain plug open too, getting every last dribble out. Surprisingly there is still some oil coming out of the oil filter adapter after a few hours, too. It's in a heated hangar, if it matters.

I guess if I needed to, I could screw the old filter back on temporarily (after all the oil oil had mostly drained out of it), close the drain plug and go ahead and top it up with the usual 8-9 quarts.

I know, I know, I should have a supply of these filters, but I'm getting a new airplane 5 months that doesn't use the same kind of filter.
 
What could possibly be bad about that? Maybe a creepy crawly finding it’s way in there but other than that, nothing to be concerned about. I’d personally leave a breathable shop towel over the oil filter opening but I wouldn’t be worried about it one bit.
 
Narwhal said:
O-470L in a C182B.

I made a mistake and did an oil change after my last flight. I figured the usual local supply shops would be open for the biggest shopping day of the year (black friday) but they were all closed until Monday, and I don't have an oil filter. Is there any harm in letting the airplane sit for 72 hours with the oil drained and filter off until I can get a new champion oil filter? I currently have the drain plug open too, getting every last dribble out. Surprisingly there is still some oil coming out of the oil filter adapter after a few hours, too. It's in a heated hangar, if it matters.

I guess if I needed to, I could screw the old filter back on temporarily (after all the oil oil had mostly drained out of it), close the drain plug and go ahead and top it up with the usual 8-9 quarts.

I know, I know, I should have a supply of these filters, but I'm getting a new airplane 5 months that doesn't use the same kind of filter.
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sounds like you have no choice.

I never stop in the middle of a oil change, like to get the oil back in asap.

hope your oil pump doesn’t drain out and could take a few seconds to re prime from sitting empty for so long?
 
Gary, only curious, what are you basing this info ( never stop, oil pump draining ) on?
 
30 years ago I drained the oil out of my shop air compressor and went to dinner. Planned to let drain during dinner. Came back with tire change on my mind that had to be done by morning on a work truck

forgot I was in the middle of a oil change and turned on my compressor with no oil in it. That was a very expensive mistake.

ever since then I never stop in the middle of a oil change.

I maintain a small fleet of trucks at work for a long time.
 
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Narwhal said:
Is there any harm in letting the airplane sit for 72 hours with the oil drained and filter off until I can get a new champion oil filter?
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No. But as mentioned covering the exposed items would be a good idea.
 
Depending on how visible the towel or cover is, also a big tag with a description of the last thing done. I often get interrupted when doing procedures in the lab, and a quick note hung visibly on the instrument tells me and others that the instrument isn't ready for use, and the next thing I should do.
 
Narwhal said:
I currently have the drain plug open too, getting every last dribble out. Surprisingly there is still some oil coming out of the oil filter adapter after a few hours, too.
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No harm in getting it all out, but as others have mentioned, tag the open drain. Adding brand new oil to "lubricate" the floor of your hangar is expensive :) .
 
Why? Not sure what the obsession is with getting all the drops out. The minute you start it.....it will begin to collect and make impurities and dirt. It's not gonna last any longer.

But, as others have said. The minute you walk away from an unfinished job....opens the door to forget to complete all the unfinished bidness.

I caught myself yesterday.....I found a screw driver in my plane...that I apparently left....inside the engine cowling. Happen to see it from the other side....after it was closed up. This stuff happens.....
 
Checkout_my_Six said:
Why? Not sure what the obsession is with getting all the drops out. The minute you start it.....it will begin to collect and make impurities and dirt. It's not gonna last any longer.

But, as others have said. The minute you walk away from an unfinished job....opens the door to forget to complete all the unfinished bidness.

I caught myself yesterday.....I found a screw driver in my plane...that I apparently left....inside the engine cowling. Happen to see it from the other side....after it was closed up. This stuff happens.....
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No obsession. If it has to sit there for 3 days with no oil I just figured why not? Plus this plane, which usually reads about 10 on the dipstick at oil changes, usually only drains out 6-7 quarts if I just let it drain for half an hour or so after flying it.
 
Also….some folks like to drain the oil bottles over night. Just to get every last drop. Lol
 
I do that. My father did that. i drain all the bottles and put it in the oil can. Never have to open a quart of oil to fill the oil can.
 
If a fly crawls into the filter threads, it could conceivably block oil flow into the small holes in the crankshaft, for instance. Knockaknock-boom. There is no filtration of any sort after that point. Oil goes into the peripheral holes in the filter, through the media, and out the middle. There's something about oil and gasoline that attracts bugs. Paint, too.

I won't leave magneto or other accessory openings open, either. People have had "little" accidents with loose hardware falling off some spot and bouncing its way into such places, and if it falls into the gearing it gets real bad real quick. Magneto retention clamps and nuts sitting on the area in front of the windshield, for instance. If you have to remove the accessory cover and maybe the sump to find something like that, you never leave anything open again.
 
Dan Thomas said:
I won't leave magneto or other accessory openings open, either.
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That’s probably a smart idea. When my mechanic sent my mags out for overhaul to QAA, he plugged the holes with shop rags and it was left that way for nearly a month.
 
I’ve seen where turning the prop pulled rags in!

Some snap on plastic coffee can tops work very well for mag holes.
 
I'd refill the fresh oil back in the sump while you wait for a filter.
IMG_0595.JPG
 
Magman said:
I’ve seen where turning the prop pulled rags in!
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Yup. It happens. Better to take a two-hole mag gasket and use it to make a carboard cover; I made mine of aluminum and used them many times.
 
Screw the old empty filter back on. Forget adding oil now. Or screw the old filter back on, safety, add oil and just go fly. Oil change intervals are very arbitrary numbers; very dependent on the type of flying (from an engineering standpoint). The original numbers on my IO-520A were change at 75 hours and have I have a screen.
 
I Never use cloth rags around motors especially red shop rags.

lint free paper towels only around motors has been my practice. fwiw
 
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Gary Ward said:
I Never use cloth rags around motors especially red shop rags. lint free paper towels only around motors has been my practice. fwiw
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FYI: just for comparison you'll find a number of aviation operators will not allow any paper towels especially rolls/boxes around aircraft/components during maintenance and only allow cloth shop rags. Paper towels can't be controlled as in tool control where cloth rags can. And the rag color of choice is red in most cases.
 
Bell206 said:
FYI: just for comparison you'll find a number of aviation operators will not allow any paper towels especially rolls/boxes around aircraft/components during maintenance and only allow cloth shop rags. Paper towels can't be controlled as in tool control where cloth rags can. And the rag color of choice is red in most cases.
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In the AIr Guard we had to check out every tool and then check it back in.
 
My shop left mine empty for about a week during annual. They put a big NO OIL sign over the starter switch. I thought that was prudent. I'm sure someone, somewhere has learned that lesson the hard way.
 
Narwhal said:
No obsession. If it has to sit there for 3 days with no oil I just figured why not? Plus this plane, which usually reads about 10 on the dipstick at oil changes, usually only drains out 6-7 quarts if I just let it drain for half an hour or so after flying it.
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I'm no expert here, but, reads 10 on the dipstick, but only drains 6 to 7, but you put 8 to 9 back in?
Something doesn't add up!
 
Checkout_my_Six said:
lint free towels won't clog if left in there? o_O
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Shop rags from a weekly supplier are re washed and many times can have metal shavings etc in them. So they are dangerous to use around motors, fine paint jobs and can even cut your hands wiping grease off.

I use them in my shops, have had a rag service for 30 years.

Like I said I don't use them around motors and do't use them to wipe off stuff off of paint for fear of scratches.

Also like has been said best not to stick any type towel or rag in your motor opening. Best not to leave that stuff open and plan according.

The OP has no choice.

FYI I have been building new motors, rebuilding motors all my life. Know what a clean room is and there are no shop rags of any kind in a clean room. The cotton off a clean, cut up tie shirt can be a problem.
 
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Gary Ward said:
Shop rags from a weekly supplier are re washed and many times can have metal shavings etc in them.
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FYI: aviation companies normally require 1st run shop rags only as part of their contract for that exact reason. The 2nd, 3rd, etc run rags would get sent to auto/truck shops after rewash. And no red rags allowed on windows or paint as we had different colored rags for that.
 
Wagondriver said:
I'm no expert here, but, reads 10 on the dipstick, but only drains 6 to 7, but you put 8 to 9 back in?
Something doesn't add up!
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This last time, my 20 quart used oil bucket was definitely less than 1/3rd full after draining, so at most 7 quarts drained, from the plug anyway. It read about 10.5 quarts before change. I added 8 quarts during the oil change and it still reads about 10.5 quarts. I have no idea why it is this way. I wouldn't expect the oil filter and associated mess to account for any more than a quart, but at least part of the filter oil ended up in the bucket too (a lot on rags and in a trashbag wrapped around the filter as it was removed). Sold the plane so not really my problem anymore. Could be a dipstick calibration issue, maybe the dipstick is calibrated to account for oil that's distributed in the engine, I have no idea. I do know that if I add more than about 10 quarts after a change the dipstick will read off the scale and I'll end up with a very dirty belly (12 quart capacity, 8 quart minimum).

Maybe my eyeballing of the 5 gallon bucket isn't accurate, but it definitely isn't half full.
 
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Wrong dipstick? O-470 in a 180 would have a different one from a 182 due to

attitude. Different engine suffix is possible also.
 
I have a large oil filter, after draining oil and replacing the filter, the filter is obviously empty. I put 11 quarts in and after running the engine the stick will show a little over 10.
My point was that if you removed 6 to 7 quarts, but put in 8 or 9, that there was some kind of math problem. I doubt there are 3 to 4 quarts remaining in the engine, oil cooler might hold a little bit, but not that much. I suspect if you actually measured the amount of oil drained, that it would be very close to the amount added after the oil change.
I realize that you no longer own the airplane, but after running the engine after the oil change, was the oil still gold and clear? Where was the dipstick level before and after the first run after the oil change?
It's not possible to drain 7 quarts and add 9 and then read the same on the stick.
 
My 0-470 dipsticks have always been wrong. Easy solution. At oil change add the minimum amount of oil you’re comfortable with. For me that’s 8 qts. Run the engine to fill the filter, stop it, and let the oil settle. Scribe a mark for 8 qts. Add two quarts, let settle, scribe a 10 qt line. Add 2 more, scribe a max fill line. Mine are a full 2 qts different from the factory marks. On the other hand, my Lycoming’s dipstick reads correctly even with an aftermarket cold air sump. But I verified it the same way.
 
There are several dipsticks for the O-470. A floatplane stick is calibrated to read accurately when the airplane is quite level. It's a long way from a taildragger stick. The airplane model, year and manufacturer makes a big difference too.

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It's real easy for someone to lose a dipstick and just go find one that fits, one that is probably wrong.
 
Mine have been the correct parts. It’s common with big Continentals.

Seaplane dipsticks are usually marked with a low and high range on the opposite side of the conventional markings.
 
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