Oil Dripping

Therookguy

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Therookguy
Howdy. I took a flight in my 182 with an O-540 J3C5D last week and after being on the ground for a while we noticed a bit of oil dripping out on the ground.

I've owned the plane for less than a year so I don't know how it acts in the hottest weather yet. It was 100*+ outside and the aircraft was sitting on the ground for about 40 minutes before I noticed it. I flew it home, with an extended stop along the way, and checked the oil before the final flight home. It read about 6 quarts. I recently got an oil change where they added 7 quarts.

I went to check on the aircraft about 24 hours later in the hangar and only noticed about a quarter sized drop. I also took the cowling off and did not see any signs of major leakage.

I checked again today after it sat in a 90*+ hangar for 48 hours and had what's in the image below. I also traced the little pipe thing and it follows right to the back of the cylinders. I know it's dripping from the pipe based on the placement of my lid.

I am definitely not a mx guru so I'd like some help deciding if this is a normal amount of leakage.

Other info:
- My chromium came back high on my oil analysis. I have steel cylinders with .01" oversize.
- Oil temp and pressures were fine all day. I was at the bottom of green at full idle after landing, but tbh I don't look there after landing very much so I don't know if that's abnormal.
 

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^ Before anyone asks the other gunk on the ground was there when I got into the hangar.
 
Chromium comes from oil control rings on the piston. Are you operating in dusty conditions? Is the air cleaner leaking air around it? Are the SCAT hoses from the air cleaner to the carb heat airbox and carb secure? No torn or loose hoses?

The breather tube looks like it might be a bit short.

That Boldmethod article on breathers is full of errors. For one thing, the breather isn't to vent vaporizing oil overboard. The aircooled engines in light airplanes have large clearances to make sure that hot pistons don't seize in cold cylinders, and so there's more combustion blowby past the piston and rings into the crankcase. That blowby contains water vapor, since burning fossil fuels does that. It has nearly nothing to do with humidity in the air. Burn a gallon of gasoline and you make nearly a gallon and a half of water, most of which goes out the exhaust, but enough gets past the rings into the crankcase. (That's where most engine corrosion comes from. Short runs, or just ground-running it, puts moisture into the case that is then not boiled off and driven out during the higher engine temperatures of flight.) There's also oil mist in the case, from all the monkey-motion and spinning stuff, and some of it is carried out the breather and makes the mess on the belly and hangar floor.

And your car does not have an air/oil separator. For one thing, the modern car's liquid-cooled engine has very tight clearances and so very little blowby into the crankcase. It has a PCV system. Positive Crankcase Ventilation. Fresh air is drawn past a filter into the crankcase and out into the intake system. The intake vacuum (low manifold pressure) provides the suction to do this. Whatever oil mist or smoke and water vapor that is drawn out is burned in the cylinders and goes out the exhaust. No breather tube, no oil drips. The PCV system won't work in the airplane because the manifold pressures are too high most of the time (no suction) so we have to make do with the breather.

Overfilling the engine oil doesn't create excess pressure. If the oil level is high, vibration splashes more of it up into the spinning stuff, atomizing it so it goes out the breather.
 
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To add to the above, chrome off the rings could come from rough cylinders caused by corrosion from infrequent use (think hours per year or winter disuse).
 
Does your oil level stabilize at 6qt? If so, no worries. Maybe leave out the extra quarts on the next oil change to save cleanup?
 
My 182-RG had an O540. If oil WASN'T dripping out of the breather tube after a flight, it would have been because there wasn't any oil in the engine. :D

yup! What do ya call a continental that’s not leaking oil somewhere? Empty :)
 
I guess the sentiment is the same whether it's Lycoming or Continental. My IO550 is drippy as well.
 
The only time my 470 leaks is after an oil change. It’s fairly low time though
 
Of course on older engines it can be more challenging to find oil leaks give general grime and previous oil spills etc tend to collect around edges of mating surfaces masking problems.

General advice… Automotive detailers have portable steam cleaners that are terrific at gently melting old oil and sludge away without chemicals. Amazing how the engine mount and engine look almost like new again making it much easier to find fluid leak issues.
 
As my mechanic told me when I bought my C150, “Kid, if it ain’t leakin a little, it’s empty.”
 
Of course on older engines it can be more challenging to find oil leaks give general grime and previous oil spills etc tend to collect around edges of mating surfaces masking problems.

General advice… Automotive detailers have portable steam cleaners that are terrific at gently melting old oil and sludge away without chemicals. Amazing how the engine mount and engine look almost like new again making it much easier to find fluid leak issues.
I use mineral spirits and a syphon spray gun. Works great.
 
General advice… Automotive detailers have portable steam cleaners that are terrific at gently melting old oil and sludge away without chemicals. Amazing how the engine mount and engine look almost like new again making it much easier to find fluid leak issues.
I use mineral spirits and a syphon spray gun. Works great.

Mineral spirits with a rag (sometimes lots of rags) and syphon spray gun is the dominant method for aircraft engine cleaning. Probably 99% use this approach. Tried and true for sure.

For me anyway, getting away from chemicals unless needed, has improved my health. I found steam actually works better and is nontoxic.

A focused steam jet really gets the crud impacted in tight corners loose and does it fast.

Especially true for caked on oil with crud. That stuff comes off in layers with a rag and mineral spirits and smears. The whole thing wipes clean in one or two passes with steam.

Unless a guy gets in there with toothpicks, Qtips, and flat blade screwdriver edged with a rag; the nooks and crannies never seem to get clean. Steam knocks it all down. One or two passes over the nose gear, firewall, engine, engine mounts, engine frame works great.
 
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I have used both steam and mineral spirits. My steam cleaner is a big machine that is a heated pressure washer. It will get water to near 212°f and will melt away grease and grime great. But it is messy and I worry that water/steam will get in places that I don't want it on my airplane.

So I use a hand held pressurized sprayer with mineral spirits on my plane belly. Just did the bottom of my plane 2 nights ago out on the ramp in front of my hangar to keep the floor clean in my hangar.

If I have a little larger job like the firewall then I use a larger pressurized tank with a hose. It's like a garden sprayer only aluminium and heavy duty.
Steam cleaner.
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Pressurized tank, can spray anything. We used gasoline in it at the races to clean parts outside. I use mineral spirits in it to de grease the plane firewall etc inside.
IMG_0226(1).JPG

I used the little metal sprayer the other night on the belly with mineral spirits in it. I tried using mineral spirits in a plastic sprayer and they didn’t hold up.
IMG_1078.JPG
 
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My wife has a steamer for her clothes and drapes and upholstery. Is that the kind of steamer you are referring to?
I borrowed her steamer when I did these seats, is this the type you used NordicDave?
IMG_9236.JPG
 
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Wow @Gary Ward serious pro steam cleaner. Thanks for sharing, very cool. We have the same Best Tugs Alpha.

I’m using a small portable unit I found on Amazon. It’s 212° steam vapor only unit at only 3 bars pressure. 5 bars is better but much more expensive. It was under a $100 and included nylon brushes on the tip as an option.

It took 1 quart of water to clean years of oil off the inside of my lower cowling. It about a pint plus to clean the firewall.

IMG_0507.jpeg
 
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Wow @Gary Ward serious pro steam cleaner. Thanks for sharing, very cool. We have the same Best Tugs Alpha.

I’m using a small portable unit I found on Amazon. It’s 212° steam vapor only unit at only 2 bars pressure. 3-5 bars is better but much more expensive. It was under a $100 and included nylon brushes on the tip as an option.

It took 1 quart of water to clean years of oil off the inside of my lower cowling. It about a pint plus to clean the firewall.

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Wow looks great! Really really clean. No way I get mine that clean with spirits. I will have to look into one, sounds like good tool/cleaner to have around a hangar where we don't have water except what we carry in.
 
@NordicDave which one did you get? The results look great.

@Gary Ward I too started cleaning with degreasers and rag with tools and nylon brushes. The small steam cleaner with it's small nylon brush melted away the tough to get crud impacted around rivet heads and aluminum edges.

I bought this unit: https://www.amazon.com/dp/B09ZHX6VLG/ref=sbl_dpx_floor-steam-cleaners_B095RHDHQD_0?th=1

It's a minimal performer, but works. I'll probably invest in a unit with higher pressure for the next one, but the price 5x. The unit will steam water diluted eco friendly degreaser.

This unit is a little more expensive, but has more options and 4 bar pressure. https://www.amazon.com/dp/B00G00BT72/ref=emc_b_5_t
 
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Not sure if it's a great comp, but my '72 arrow (lycoming io-360-c1c6) routinely drips out a bit of oil after flight. It's not much, certainly not enough to cause worry, but ******** it is consistent.
Now I think I'd be more worried if I *didn't* see that oil. I just put a tray to catch it and monitor to make sure it's not dripping TOO much.
 
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