Oil drips

skidoo

skidoo

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skidoo
OK, my new 5 year old 182 just came out of annual and flown under 15 hours. Looking under the cowl, I see several places where hoses are clamped and clean oil seeping through, a little drip on the exhaust manifold etc. There is not a whole lot, but you can tell that some hoses and area are moist with oil. Is this common, or should I go through or have my A&P try to tighten up/seal the hoses better?

I had an A&P friend take a quick look and he said that what was there was fairly common. Any reason, oil leaks can not be eliminated and keep a clean engine area?
 
skidoo said:
I had an A&P friend take a quick look and he said that what was there was fairly common. Any reason, oil leaks can not be eliminated and keep a clean engine area?
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I am not an A&P but there is no reason that I can think of to have leaks.

I do get spray from my breather tube, but my engine compartment is very clean and when I do see a leak I look very closely at where it is coming form and then clean it up.

Now if you have an engine like Greg's, leaks are much more common. In my 0320 they are not.
 
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skidoo said:
OK, my new 5 year old 182 just came out of annual and flown under 15 hours. Looking under the cowl, I see several places where hoses are clamped and clean oil seeping through, a little drip on the exhaust manifold etc. There is not a whole lot, but you can tell that some hoses and area are moist with oil. Is this common, or should I go through or have my A&P try to tighten up/seal the hoses better?

I had an A&P friend take a quick look and he said that what was there was fairly common. Any reason, oil leaks can not be eliminated and keep a clean engine area?
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The typical life of an engine hose is 5 years. Perhaps it's time to have your mechanic start changing out these hoses.
 
Rotor&Wing said:
The typical life of an engine hose is 5 years. Perhaps it's time to have your mechanic start changing out these hoses.
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Lycomings typically start leaking at the rocker cover gaskets (they're cork, the cover screws get get overtightened and pinch the gasket, or they'll harden from the heat and then crack) or at the rocker box drain tube hose connections at the crankcase nipples. The screw clamps on those can back off a little.

There's an AD against some defective Lycoming oil filter adapter gaskets that start getting pushed out. Better to ask your mechanic about it.

The rocker cover gaskets should be replaced with the silicone gaskets.

Dan
 
Dan Thomas said:
The rocker cover gaskets should be replaced with the silicone gaskets.
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I've use both on my plane. The silicone ones last longer, but the cork ones are better at sealing leaks if you've got bad ones, albeit requiring more frequent replacement. As a result, some of my cylinders have silicone and some have cork. Of course, my rocker box covers don't even match, so clearly I'm more concerned with functionality than appearance of the engine.

I wouldn't say that one "should" replace the cork ones with silicone ones. If the cork ones wear out and start leaking, try the silicone ones. If the silicone ones leak, try cork.
 
Ted DuPuis said:
I've use both on my plane. The silicone ones last longer, but the cork ones are better at sealing leaks if you've got bad ones, albeit requiring more frequent replacement. As a result, some of my cylinders have silicone and some have cork. Of course, my rocker box covers don't even match, so clearly I'm more concerned with functionality than appearance of the engine.

I wouldn't say that one "should" replace the cork ones with silicone ones. If the cork ones wear out and start leaking, try the silicone ones. If the silicone ones leak, try cork.
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In our fleet of seven Lycomings, no silicone gasket has ever leaked. The corks, on the other hand, have often started leaking within a couple hundred hours. The silcione gaskets we use are about 1/8" thick.

Sometimes you'll find the covers distorted by guys overtightening the screws while trying to stop a leak. Such covers will tend to leak no matter what, unless they're tapped straight again. And overtightening a silicone gasket can extrude it into the rocker cavity at the screws, letting oil into the gasket's now-enlarged screw hole and out around the screw threads. Backing the screws off and retightening them a bit more gently can fix that.

Dan
 
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It depends on you, and your A&P, and your bank account. A little oil is quite normal in a 182, but can be eliminated with enough money. If your A&P says it's OK and you are Ok with with it, then it is fine. Otherwise start shelling $ until the leaks are acceptable to you and your A&P. These small leaks often tend to loosely follow the 90/10 Rule where the last small leak will cost the most to fix.

Brian
CFIIG/ASEL
 
Dan Thomas said:
In our fleet of seven Lycomings, no silicone gasket has ever leaked. The corks, on the other hand, have often started leaking within a couple hundred hours. The silcione gaskets we use are about 1/8" thick.

Sometimes you'll find the covers distorted by guys overtightening the screws while trying to stop a leak. Such covers will tend to leak no matter what, unless they're tapped straight again. And overtightening a silicone gasket can extrude it into the rocker cavity at the screws, letting oil into the gasket's now-enlarged screw hole and out around the screw threads. Backing the screws off and retightening them a bit more gently can fix that.
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Well, on my fleet of two Lycomings (I know, less than 7 but more than 1, and a combination of 12 cylinders), I had a persistent rocker cover gasket leak that would not go away with the silicone gaskets (on two cylinders, no less), but the cork sealed it up just fine. Yes, we did ensure that the silicone one was properly torqued down and adjusted several times. After fiddling with it for two months I put cork ones on and the problem went away entirely. I'm not disputing that the cork ones don't last as long, but I can tell you that I've personally observed a situation where they sealed better than the silicone. I've heard of other such cases.
 
Dan Thomas said:
Lycomings typically start leaking at the rocker cover gaskets (they're cork, the cover screws get get overtightened and pinch the gasket, or they'll harden from the heat and then crack) or at the rocker box drain tube hose connections at the crankcase nipples. The screw clamps on those can back off a little.

There's an AD against some defective Lycoming oil filter adapter gaskets that start getting pushed out. Better to ask your mechanic about it.

The rocker cover gaskets should be replaced with the silicone gaskets.

Dan
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Dan -- perhaps you can shed light on the availablity of gaskets for the Lycoming 0-145-b2?

Ive heard some horror stories about availability and pricing... :eek:
 
I just had two leaks fixed. Both occurred at the same time. One was the quick oil drain. It wasn't the internal o-ring. It was leaking around the crush washer. Apparently it wasn't safety wired correctly and backed off just a hair. The other was a bad gasket on the oil cooler.
 
dmccormack said:
Dan -- perhaps you can shed light on the availablity of gaskets for the Lycoming 0-145-b2?

Ive heard some horror stories about availability and pricing... :eek:
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Oh, man. That's a rare engine. Even Univair has only the service and parts manual, no parts at all that I can see. Those horror stories are probably true.

My airplane originally had an O-145 on it, but as it came out tail-heavy and the engine couldn't be moved forward because the bed-mount tubing would change angles and interfere with the mags, we put an A-65 on it. The Lyc was really, really smooth as I remember, but I was flying behind a Gipsy Major at the time and anything would feel smooth after that.

Dan
 
brcase said:
It depends on you, and your A&P, and your bank account. A little oil is quite normal in a 182, but can be eliminated with enough money. If your A&P says it's OK and you are Ok with with it, then it is fine. Otherwise start shelling $ until the leaks are acceptable to you and your A&P. These small leaks often tend to loosely follow the 90/10 Rule where the last small leak will cost the most to fix.

Brian
CFIIG/ASEL
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+1.

My five six year old factory remaned engine "sweats" a small bit of oil from the pan gasket (not enough to drip, just "wet") and I have some small drip leaks from the push-rod tubes.

NONE of this is enough to make me loss any significant oil or cause problems, however trying to get them all stopped would take a lot of $$$. Oh and mine is a Continental.....
 
tdager said:
+1.

My five six year old factory remaned engine "sweats" a small bit of oil from the pan gasket (not enough to drip, just "wet") and I have some small drip leaks from the push-rod tubes.

NONE of this is enough to make me loss any significant oil or cause problems, however trying to get them all stopped would take a lot of $$$. Oh and mine is a Continental.....
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Oh. A Continental. Weren't they designed by Harley Davidson?:D

Dan
 
I had an A&P friend take a quick look and he said that what was there was fairly common. Any reason, oil leaks can not be eliminated and keep a clean engine area?
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I have chased engine oil leaks on the three planes I've owned, and come to one conclusion: Lycomings and Continentals are like mid-'70s AMF Harley-Davidsons. Sure, you can cure one oil leak, but there will still be 238 other potential oil leaks to deal with down the line.

I even went so far as to install an air/oil separator on Atlas (our Pathfinder), because I wanted a perfectly clean plane. My old A&P (40+ years in the business) just chuckled and installed it, happily taking my money...

Three years down the line, I'm still chasing the occasional oil drip. Just new ones, coming from other locations... :rolleyes:
 
Jay Honeck said:
I have chased engine oil leaks on the three planes I've owned, and come to one conclusion: Lycomings and Continentals are like mid-'70s AMF Harley-Davidsons. Sure, you can cure one oil leak, but there will still be 238 other potential oil leaks to deal with down the line.

I even went so far as to install an air/oil separator on Atlas (our Pathfinder), because I wanted a perfectly clean plane. My old A&P (40+ years in the business) just chuckled and installed it, happily taking my money...

Three years down the line, I'm still chasing the occasional oil drip. Just new ones, coming from other locations... :rolleyes:
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If you're only chasing the occasional oil drip then you're doing pretty well.

My instructor was explaining to me lubrication of the Aztec's landing gear. One of the things he said was "The nose wheel is the one that will always be the one to have lubrication issues, because the mains..." (points to the oil leaks coming from each engine) "...are self-lubricating!" Sure enough, the mains are pretty well lubricated from the healthy marking of its territory that my Aztec does.

Remember, these engines were designed in the days when most engines leaked unless they were out of oil. Not much has changed on our engines since then, especially with regard to sealing technology. The barriers to certification are part of this. Add into it the fact that most engines have been overhauled a couple times and are not new, and, well...

Since I was raised on British cars, I'm used to a vehicle marking its territory. All leaks are just gaps that need to be sealed, so they can be fixed. It's just a matter of how much time and effort you want to put in. Personally, I'd rather get the cabin leaks sealed so that it's warmer in there. Brr... it's cold inside when it's 0F outside at night!
 
Ahhh british cars..loved those electronics (lucas?) on my dads old austin america in the late '60s early '70s and trying to tune those oil bath carbs - IIRC 2 carbs on a 4 cyl engine, impossible to keep them in synch with each other.

Oh and as for the oil leaks, we had a situation with some oil drips with one of our fleet 172s, and our A-P took us in to see it and he said that when its very very cold, some of the moisture that forms in the oil supply tends to seep out of the plane and can show as a 'leak'. I probably explained this incorrectly, but thats the jist of what I think he said to us.
 
Sorta like back in the day when I was flying radials. We use to say "it's not leaking oil, it's just marking it's territory!"

Those were the days we bought oil by the gallon, no quart containers.
 
Dan Thomas said:
Oh. A Continental. Weren't they designed by Harley Davidson?:D

Dan
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LOL...yeah I think so. My VERY experienced, crusty A&P said "we can fix it, it will cost you $$$, and it WILL leak again sometime in the future....it is a Continental".

Since it poses no risk and does not even get the engine compartment that oily, I just leave it alone. Hell for me the best "stop oil leaks" method was to stabilize at 10 qts in the engine instead of 12...the first two just get dumped out and all over the belly anyways if I fill to 12!
 
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