Draining the Oil Filter / How not to make a mess

OK, maybe I'm just a slow learner, and everyone else figured this out long ago.....

I have posted before about my problem getting the oil filter to drain completely when I am doing an oil change. As a reminder, I've got an angle adapter on the back of my TMXO-360, so the filter sticks up and left at a 45 degree angle. I have tried all of the tips suggested before, including punching holes int he filter to let air in so that it can drain. Most other suggestions relate to making sure that when the filter DOES drip oil as you unscrew it, said oil doesn't make a mess - catching it, soaking it up, etc. I've gotten pretty good at those things, and have a nice technique using a couple of paper towels and a large zip-lock bag...but still, I end up with a filter with oil in it.

Well yesterday, I had a revelation! I did all the normal things for an oil change - drained it hot, even punched some holes in the filter. Sure enough, when I spun it off, it still had a good third of a can of oil. But this time, I noticed that the oil filter adapter (on the engine) was full of oil as well. And then it hit me....(here comes the incredibly obvious point that I have been missing!)....THE VALKYRIE IS A TAIL DRAGGER!

Sure enough, it looked to me like the bottom quarter or so) of the oil filter can't drain, because it would have to do so up hill with the tail on the ground. I picked up the tail and put it on the saw horse I keep for tail wheel maintenance, and the oil in the adapter drained away into the engine. It seems pretty obvious now - I just never was in the habit of putting the tail up for oil changes - gee, I never did that in twenty-some years with my Grumman! (Tricycle gear, of course....)

SO now I have to wait for another 50 hours to confirm that the filter will drain completely if I lift the tail up. Maybe this is finally a good excuse to buy one of those fancy tail wheel lift thingies....I always seem to wrench a shoulder in the awkward position it takes to lift it by hand....

Whew....I'm glad I am now not the only person left who hadn't figured this out!

Yes,

Gravity, ya reckon?

Regards,

Another good reason to put the wheel up front! lol

Love the tail lift thingy.

Couldn't agree more with those that like the 'tail lift thingy'. Danny borrows it all the time - makes dealing with anything engine related easier. Once raised I usually slip a saw horse under.

Pic here with previous engine/prop:

Thats Disgusting!

Such a clean hangar...I haven't had time to even tidy mine up since I finished building 100 hours ago!

Frank..7a IFR checkride in 10 days..Gulp!

Ironflight said:

OK, maybe I'm just a slow learner, and everyone else figured this out long ago.....

Click to expand...

I tried a new method yesterday: drain it in 25F weather! It barely moves at all, so any drops that make a break for it are easily caught and dealt with. Of course, it's going to take days to drain it all out of there, but....

Oil Filter Check Valve

Well heck, now I've got a PM from a well-known engine expert telling me that the filters do have a check valve, and will retain oil for "a long time". I guess that putting the tail up on a stand will still let the oil in the adapter drain out and reduce that drip potential.....

Just when you think you've got things figured out, along come some facts....

So how cold do I have to get the filter to freeze the oil to a gel? Maybe I should hit it with a CO2 extinguisher before removing it!

Paul

Paul,

FWIW, I raise the tail to drain the sump, and then I lower the tail to drain the oil filter (poke holes in the back of the filter, drain it into a funnel/tube/catch can). I let it sit for several hours, overnight if possible. Works every time with no mess.

Sometimes coming back to a job the 2nd day lets you see things you might have missed the first day, too!

Straight or Angled Filter Adapter?

dan said:

Paul,

FWIW, I raise the tail to drain the sump, and then I lower the tail to drain the oil filter (poke holes in the back of the filter, drain it into a funnel/tube/catch can). I let it sit for several hours, overnight if possible. Works every time with no mess.

Click to expand...

Dan - does your filter go straight back out of the case, or is it the angled adapter? When you say that you poke holes "in the back of the filter", that sounds like a straight adapter. The trouble withe the angled adapter like I have is that basically, the mouth of the filter is pointed down, so when you unscrew it and break the seal, the first thing it does is dump any residual oil.....

Paul

Another Good Reason?

Geico266 said:

Another good reason to put the wheel up front! lol

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I haven't really heard on ANY good reason to put the wheel up front!

Champion CH 48108-1

It is my understanding from an A&P friend of mine that Champion has a filter (CH48108-1) that has a check valve in it. Unfortunately it is supposed to fit the ECI 90 degree adapter only.

Wes Hays
Winters, TX

That's the one!

....48108-1 is what my engine takes.....so, in the end, it's probably good that I have perfected my zip lock/paper towels technique.....but lifting the tail still does help the adapter drain, giving a little less leakage....

Paul

Ah...yep. I do have a straight filter, not an angle adapter. (better to reply late than never?)

Hey Iron horse..

this cost a few cents, but it could pay for itself in time savings.

http://www.vansaircraft.com/cgi-bin...3237516-106-534&browse=new&product=drain-tool

I myself have built somthing similar but this looks like a nice package.

just another tool to purchase..

I initially had a real mess changing my filter.

For those who have mounted the oil cooler down on the firewall, a friend of mine installed a tee fitting on the lowest port on the cooler. I of course stole the idea and put one on mine.

Unbelievable difference on oil filter changes. I open the bottom of the tee fitting when I drain the oil, and it allows nearly all of the oil in the filter and cooler to drain also. After it cools, I put a baggie over the filter and screw it off. Very little oil in the baggie.

Anyway just a FWIW. It really did help clean up the process at oil filter changes.

BTW, I also have the oil filter coming straight out the back of the accessory case.

Wes Hays
Winters, TX
RV-6A Flying

oil draining

A friend of mine pokes a hole at the end of the filter closest to the 1 inch socket grip but on the side of the filter. he then applies 20psi from a rubber air blower chuck and the oil goes right out of the filter and the lines. curious to see what this does to the rest of the engine.. anyone?

Also as a ps.. use the box the oil filter comes in to make a long V for the oil to drip down... or a piece of 20 thou metal 25 inches by 2 inches in a V shape works Really good... just unscrew the filter a little bit to let the oil start to come out at a controlled rate.
Best
Brian

brianwallis said:

A friend of mine pokes a hole at the end of the filter closest to the 1 inch socket grip but on the side of the filter. he then applies 20psi from a rubber air blower chuck and the oil goes right out of the filter and the lines. curious to see what this does to the rest of the engine.. anyone?
SNIP

Click to expand...

I believe the outside of the filter is what is pressurized when the engine is running (oil moving through the filter inward). So, blowing pressurized air into this space could push crud the filter has caught back into the galleys leading from the oil pump. I don't think I'd do it.

I minimize the mess by draining the oil when the engine is hot, but leaving the filter for the next visit to the hangar. I also poke a small hole in the top of the filter can, allowing most of the oil to drain overnight. When the oil is room temperature, it is much, much easier to contain the slop. I put a cut off gallon milk container under the filter. I then use a baster to remove most of the oil from the milk container before tilting and removing it.

Question Alex....straight back filter, or angle adapter (sticking up at a 45 degree to the side, "mouth" down)? Just want to make sure we're not talking apples and oranges...

Paul

Dumb Question?

If the tail is down and there is some oil left in the filter, why run it into the engine as opposed to just pulling off the filter with the oil still in it? A little sheet metal V will catch the stuff that tries to trip from the forward face where the big O ring is and you need that or something like it anyhow, right? My third wheel is in front, so I am just not familiar with the issue.

No Dumb Questions!

hevansrv7a said:

If the tail is down and there is some oil left in the filter, why run it into the engine as opposed to just pulling off the filter with the oil still in it? A little sheet metal V will catch the stuff that tries to trip from the forward face where the big O ring is and you need that or something like it anyhow, right? My third wheel is in front, so I am just not familiar with the issue.

Click to expand...

The problem is that with the angle adapter, the moment that you break the seal on the filter (as you spin it off), everything downstream of the filter's check valve, and trapped in the adapter (by having the tail low) dumps before you can get the thing spun the way off. Sure, you can come up with all sorts of clever ways to catch it (although even the clever sheet metal V drain troughs I have seen still bathe the adapter in oil), but the idea here is the pursuit of the Holy Grail - the dripless oil filter change! Just call me Don Quixote....

Ironflight said:

Question Alex....straight back filter, or angle adapter (sticking up at a 45 degree to the side, "mouth" down)? Just want to make sure we're not talking apples and oranges...

Paul

Click to expand...

Straight back, tricycle gear.

I have the same set up as Paul. The 45 degree adaptor, with a spacer, on a TD RV8.
The last time I changed oil, I did the following and the oil did drain out of the filter.
With a still warm engine, I punched a hole in the top rear of the oil filter. While draining the oil, I lifted the tail and left it in the up position for about an hour. Then put the tail back on the ground and let everything drain over night. The next day, I took off the filter, expecting a bunch of oil, but it was almost dry.
I was getting oil from the filter in previous oil changes, but I didn't use this sequence, so I don't know if this is a fluke, or not. At any rate, at least the filter is easy to get at.

sf3543 said:

I have the same set up as Paul. The 45 degree adaptor, with a spacer, on a TD RV8.
The last time I changed oil, I did the following and the oil did drain out of the filter.
With a still warm engine, I punched a hole in the top rear of the oil filter. While draining the oil, I lifted the tail and left it in the up position for about an hour. Then put the tail back on the ground and let everything drain over night. The next day, I took off the filter, expecting a bunch of oil, but it was almost dry.
I was getting oil from the filter in previous oil changes, but I didn't use this sequence, so I don't know if this is a fluke, or not. At any rate, at least the filter is easy to get at.

Click to expand...

I had this exact same experience on one oil change, a few chanegs back Steve...it gave me hope that I was coming up with a clean system....Alas, when I repeated it the next time, the silly filter dumped all over again....

Paul

Changin' the Oil

What's the trick to changing the oil w/out getting it all over everything?
Rolly Clark

Rolly9 said:

What's the trick to changing the oil w/out getting it all over everything?
Rolly Clark

Click to expand...

Rotate the plane 180 degrees. If that is alot of work or your hanger is not tall enough you can loosen the oil filter, place a plastic bag over it and take it off the rest of the way. Works for me, just take your time.

Draining oil out of the sump is easy. Just make a gutter out of something and wire it in place.

Rolly,

Changing the oil is easy, you just gotta have the right helper.



The trick is to get the filter off. I do the same thing Larry does, use a bag, not tip the plane up on its nose.

Ditto on the plastic bags. I use the the grocery store kind. Slide one handle over the filter after you have loosened it. I have about 5 years of oil change bags stored before they outlaw them here in the peoples republic of CA.

Oil Change Mess

Only relief on oil filter droppage is to drain it cold with no oil in the filter. But then the oil analysis people tell you that you have a high fuel content in the oil because you must not have warmed the oil properly! Smart guy's the analysis people! To save the mess when I remove the oil screen is to cut a water bottle at an angle and place it beneath the screen when I back it out and that catches about a whole bottle worth of oil.
Randy Utsey
RV-7
N55CU
Charlotte, N.C.

Rolly9 said:

What's the trick to changing the oil w/out getting it all over everything?
Rolly Clark

Click to expand...

A long time ago with a 0-360-A4K I used to make a heck of a mess when changing oil filters. That darn horizontal filter mount was impossible get drained enough to not make a mess.

Then I found a kit that worked pretty good. It was a punch, a hose and a large hose clamp. The clamp had a nipple with an O Ring installed in it. Punch the hole in the top of the filter, put the clamp around it and put the nipple into the small hole you just punched into it. Install the drain hose and rotate the filter half way so the hole is on the bottom side. Then go home and let the oil drain from the filter. What little oil was left was easy to contain with a shop rag.

ACS sells a better version than the one I described here

To prevent the mess from the oil filter, I made a "V" shaped piece of aluminum scrap, long enough to go from the bottom of the filter to the side of the aircraft, I loosen the filter just enough for the oil to start leaking out. It hits the aluminum and is directed to the side where it drips into a bucket. Don't get a drop on the firewall. There is even a handy hose under the filter to rest it on so I don't have to hold it.

The channel is about two inches wide, and bent into a gentle "V". I think I got the idea in this site a couple of years ago

Cheers.

Joe Hine
RV4 C-FYTQ
Fredericton NB
Canada

yes

I do what Joe does, I have a rather long piece of aluminum angle stock that I put just underneath the oil filter. I loosen the oil filter just enough to let the oil run down the V-channel to a bucket. Works like a champ!!!!
Best
Brian Wallis

Rolly9 said:

What's the trick to changing the oil w/out getting it all over everything?

Click to expand...

Rolly,

Since you asked, here's a shameless little plug: You might like using the Form-A-Funnel, which was made just for this job. It's easy to clean, and it rolls up to a compact size, so you can put it in your aircraft's tool kit and have it with you all the time.

If you need any further information, just let me know...

Buck
VP, Form-A-Funnel