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Oil change question

MarkCFI

Active Member
I went to change the oil in my RV-4 O-320 E2D today and after warming it up and pulling the cowl I didn’t have an appropriate tool to remove the 1/2” square oil plug.

This would be the first time I’ve changed the oil myself so was caught a bit empty handed.

Is there a socket available for that? Or is it usually done with a 1/2” open ended wrench? I didn’t have that in the hangar either.
 
I've never needed a wrench to drain the oil on an airplane. Does the plane have a quick drain similar to the one pictured below? All the planes I've been involved with in the last 15 years had one installed at some point.

Quick drain valve.JPG

I'm sure a more knowledgeable VAFer will be along to assist further any minute now.
 
I went to change the oil in my RV-4 O-320 E2D today and after warming it up and pulling the cowl I didn’t have an appropriate tool to remove the 1/2” square oil plug.

This would be the first time I’ve changed the oil myself so was caught a bit empty handed.

Is there a socket available for that? Or is it usually done with a 1/2” open ended wrench? I didn’t have that in the hangar either.

Open ended wrench will work fine. NO adjustable wrench please.
I do have the quick drain show in post above and highly recommend.
 
Yes, you can buy an 8 point socket for square heads. Most socket sets will come with a few of those in standard sizes.

I agree with others that replacing with a quickdrain is the way to go. Especially since they will have a hose connection and you can contain the flow of the old oil into the drain pan. Check out the Fumoto quick drains (search here on VAF for other threads). High quality, and less expensive than the aviation versions.
 
Thanks.

I’ll take my open ended wrenches to the airport next time.

I do have one of the Safeair P5000 quick drains to install. But I couldn’t get the existing plug out so was stuck there.

I thought for sure I would have something already at the hangar but the 4 point plug threw me off. I just assumed I would be able to engineer something with all the swivels and adapters I had, but that was a no.

Thanks very much for all the replies.
 
If you have a 12 point socket set you should be able to remove a square plug. Most sockets for DIY are 6-point so they won't work. I highly recommend a socket over an open-end wrench.

-Marc
 
Pipe wrench, channel locks, or crescent wrench will easily remove a square plug. If you pay attention the chance of rounding the edge of the plug is very small.
 
I've never needed a wrench to drain the oil on an airplane. Does the plane have a quick drain similar to the one pictured below? All the planes I've been involved with in the last 15 years had one installed at some point.

View attachment 34304

I'm sure a more knowledgeable VAFer will be along to assist further any minute now.

This! It makes oil changes super easy. I have a hose I attach it to letting it drain into a 2.5 gal collection can from autozone. Easy to take oil samples mid stream with this device too.
 
Check out the Fumoto quick drains (search here on VAF for other threads). High quality, and less expensive than the aviation versions.

I have my Fumoto ready to go on. But my engine is pickled and is now filled with 12 quarts of pepboys oil. So I need to remove the square plug with 12 quarts behind it. Gonna be fun the first time.
 
If you have a 12 point socket set you should be able to remove a square plug. Most sockets for DIY are 6-point so they won't work. I highly recommend a socket over an open-end wrench.

-Marc

I was this many days old when I learned this. Much appreciated.

I actually think I have multiple sets of 12 points but I usually shy away from using them to avoid rounding off so I never even tried them.

I only need to get the plug out once so I think I’ll try this next.

Again, thanks for all the tips.
 
I went to change the oil in my RV-4 O-320 E2D today and after warming it up and pulling the cowl I didn’t have an appropriate tool to remove the 1/2” square oil plug.

This would be the first time I’ve changed the oil myself so was caught a bit empty handed.

Is there a socket available for that? Or is it usually done with a 1/2” open ended wrench? I didn’t have that in the hangar either.

Mine takes a 9/16" open ended wrench. If you don't keep a set at the hanger, be sure to bring both sizes. Also, with the appropriate sealant, there doesn't need to be a crazy amount of torque on that plug. Due to the exhaust placement, I can't fit a quick drain plug, so I've resigned myself to removing and installing that plug 40-50 times before the engine goes in for overhaul. I'm hoping the threads last that long.
 
Due to the exhaust placement, I can't fit a quick drain plug, so I've resigned myself to removing and installing that plug 40-50 times before the engine goes in for overhaul. I'm hoping the threads last that long.

The builder of my airplane (with an IO-360-M1B) replaced the oil drain plug with this fitting:

AN816-10D NIPPLE - FLARED TUBE AND PIPE THREAD

and cap:

AN929-10 FLARED CAP ASSEMBLY # 10 ALUMINUM

Just remove the cap to drain the oil. Will save the oil sump drain plug threads. A buddy saw my setup and installed those components to his engine too.

I tried to fit a Fumoto quick drain, but the intake pipe was in the way so couldn't do it.
 
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Take any two half inch drive sockets, weld em together (just rod welding is Ok) then you can use you socket ratchet or extensions etc
 
The builder of my airplane (with an IO-360-M1B) replaced the oil drain plug with this fitting:

AN816-10D NIPPLE - FLARED TUBE AND PIPE THREAD

and cap:

AN929-10 FLARED CAP ASSEMBLY # 10 ALUMINUM

Just remove the cap to drain the oil. Will save the oil sump drain plug threads. A buddy saw my setup and installed those components to his engine too.

I tried to fit a Fumoto quick drain, but the intake pipe was in the way so couldn't do it.

That's a pretty good idea. I'll get a steel one on order and see if it fits during the next oil change. It's way too close to the exhaust for me to feel comfortable putting an aluminum fitting there.
 
That's a pretty good idea. I'll get a steel one on order and see if it fits during the next oil change. It's way too close to the exhaust for me to feel comfortable putting an aluminum fitting there.

FWIW, I have the AL fitting and cap and it's worked well for 1280 hours so far. No signs of any heat damage with the IO-360-M1B.

I have a loop of safety wire wrapped around the cap, as seen in the pic below. It takes many turns of the cap before any oil begins to leak out. I've always found the cap tight when removing it for oil changes. Use two wrenches when removing the cap, one to hold the fitting and one to remove the cap.

i-2x4WqjW-XL.png
 
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Pic shows what I'm working with. The half-raven return is too close as well, but I was able to fit a heat shield in there so there's some comfort level there. The other drain dumps basically onto the exhaust. I'll do some test fitting during the next oil change and see if it's worth pursuing.
 

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Pic shows what I'm working with. The half-raven return is too close as well, but I was able to fit a heat shield in there so there's some comfort level there. The other drain dumps basically onto the exhaust. I'll do some test fitting during the next oil change and see if it's worth pursuing.

After looking at your picture, you probably have a nice smoke system after each oil change for a few minutes.

Thats tough to make work. I would suggest putting an elbow on to move it outside the exhaust but it looks pretty tight to be able to spin the elbow on. I know there are some pretty small brass fittings that may work but may be more trouble than it is worth. Good luck.
 
similar conflict on my 4 pipe exhaust. I replaced the plug with a 45 deg street-ell, then was able to put a quick drain into that.
 
similar conflict on my 4 pipe exhaust. I replaced the plug with a 45 deg street-ell, then was able to put a quick drain into that.

I tried putting a 90 degree elbow in when I first noticed the quick drain wouldn't fit, only downside is I have to drop the exhaust to install it. Maybe at annual.
 
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After the elbow, you may want to install a short length of pipe before the quick drain to get the o-ring in the quick drain away from the heat.
 
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