High oil temp. Or is it?

[labbadabba]

I noticed when I did the pre flight of our club's beat up 172 that oil was all over the inside of the cowling and had streamed outside. To the point I was worried the static port would be clogged. I told myself that if the pressure was okay on run up then it's a go. Well oil pressure was fine and I set out for a short 60nm XC. (building hours for my IR). I did a couple stop and goes for my night currency and to make sure the bird was happy. Shortly after I was on my way. About 10 mins into the XC, I noticed the oil temp near the red line at a 2400 rpm cruise. I know the gauge is green up to the red line but I was not comfortable on a night solo XC. How hot does the oil normally run in a 172 at standard temp? Is it unusual to be close to red line?

Gave me the creeps. Was on with FF and center kept asking if I was declaring an emergency.

 

[poadeleted20]

With that much oil loose, I would not have flown the plane without a mechanic looking at it. Note that high oil temperature is one symptom of low oil level. Makes me wonder just how much oil was left in the engine when you landed. Might be you were real lucky not to have had a much worse outcome.

 

[N801BH]

With that much oil loose, I would not have flown the plane without a mechanic looking at it. Note that high oil temperature is one symptom of low oil level. Makes me wonder just how much oil was left in the engine when you landed. Might be you were real lucky not to have had a much worse outcome.

Agreed....

Who in the hell would take off in a plane with an obvious oil leak ??

 

[TEFLONSEAN]

WOW!!! Mindboggling decision....glad YA got home safe.

Oil leak to the point where you worried about static port being an issue. And you launched because oil pressure was good???

 

[jordane93]

With that much oil loose, I would not have flown the plane without a mechanic looking at it. Note that high oil temperature is one symptom of low oil level. Makes me wonder just how much oil was left in the engine when you landed. Might be you were real lucky not to have had a much worse outcome.

 

[Stewartb]

The presence of oil isn't necessarily an indication of un-airworthiness. Some airplanes leak oil. Pressure cowls make it go everywhere.

Range gauges aren't all the same. You can change a sender and it'll be different than the one before. Change it a fe more times and you might find one that's similar to what you're used to. Owners can validate a range with a ground temp test. Renters aren't able to. Green is green, red is red. That's all you've got.

 

[kontiki]

I'm curious how much oil it had in it when you took off. What did the dipstick show on preflight?

On the rental 172 I did my primary flight training in, for a while they used an oil temp sender for the wrong temp range which made it indicate high. Apparently they had some trouble finding the correct part, and rather than ground it, they used what they had. It would only reach redline in the hottest summer months at lower altitudes.

I really didn't like it. The CFIs always encouraged the customers to make sure the owner knew they didn't like some of the short cuts. They had no clout.

 

[dell30rb]

Our club 172sp's are training machines. mostly good weather training flights. Fly one through some light/moderate rain and you will get a ton of grey oil/water streaking across the body. Just normal leakage over many hours, washed out by the rain.

The gauges can be suspect, unless you have a good engine monitor its hard to know exactly. factory gauges can read high, but unless they get into the red, I don't really worry about it.

Best practice with an unfamiliar airplane is to get it cruising at poh settings when in good vfr. CHT and oil temp should settle out in the green. if not, land asap

 

[labbadabba]

Oil had just shy of 6 quarts prior to start up. Planning on being back at the airport first thing tomorrow to check where it ended up.

I think tonight was one of those 'license to learn' kind of nights...

 

[kenjr]

I think tonight was one of those 'license to learn' kind of nights...

Understatement of the year. No freggin' way I'd even fire the plane up with an obvious oil leak...let alone go flying at night.

As for the '...or is it..." Do you really want to find out at 7500' at night?

Wow. Glad your safe.

 

[labbadabba]

To be fair, I WAS concerned about a leak, or maybe the dipstick or oil cap was loose. Oil pressure was solid during run-up and operation.

 

[woodchucker]

Just curious if you RTB'd it after that 10 minutes?

 

[JHW]

Single engine at night, no thanks. Departing day or night with an unexplained oil leak, no thanks. Making the first flight after any maintenance at night, no thanks.

 

[labbadabba]

Yeah, I had two airports in gliding distance between my home field and where I turned back.

I dialed back the RPMs and went full rich. The temp didn't rise but was still high (still in the green but almost to the red line). Since it was holding, and had alternates I felt more comfortable trying to make it all the way back.

 

[yakdriver]

Obvious oil leak and the dipstick was under 6 quarts. If it had that much oil all over the airplane and it is dripping off the bottom there is no way you should have flown without investigating the source. At the very least you should have added a quart. If that is an airplane that you regularly flew did it have a history of leaking oil? If it was your airplane would you have flown it? I'm betting it is down to under 4 quarts. If less than that you probably caused some engine damage. Don

 

[Cpt_Kirk]

Oil had just shy of 6 quarts prior to start up. Planning on being back at the airport first thing tomorrow to check where it ended up.

I think tonight was one of those 'license to learn' kind of nights...

Live and learn.

In my opinion, had I seen the same thing, especially at night, I would have called it off.

 

[peerlesscowboy]

To be fair, I WAS concerned about a leak, or maybe the dipstick or oil cap was loose. Oil pressure was solid during run-up and operation.

The oil pressure won't tell you much about oil quantity until you're so low that the pump starts sucking air.

 

[N64543]

Wow! License to learn can also be license to kill myself and worse others. As a low time cessna 172 owner and past renter I can say in my 367 hours of dealing with c172 I have never experienced oil in cowling like you mentioned. If after seeing this you can't answer the question of why this is happening then you shouldn't fly the plane until a mechanic evaluates the situation. I know the feeling when you are all ready to go but when something is askew better to figure it out on the ground , aviation can be very unforgiving.

 

[iflyvfr]

You didn't say which 172 model you were flying. In the Continental equipped older models, it's difficult to keep dry in my experience. The valve covers will leak if overtightened or if a gasket is pinched, and the push rod tubes are infamous for leaking return oil. That's why Real Gaskets has the pushrod tube STC to fix that. A little bit of oil goes a long way when its hot and swirling around under the cowling.

That said, what were the outside temps when you were flying? I have seen my oil temp gauge at, but not touching red line in the summer. Yesterday it was past 1/2 way in the 40*+ F weather we had. I would not fly with oil < 6 qts., but not sure what the newer models require.

 

[Geico266]

Live and learn.

In my opinion, had I seen the same thing, especially at night, I would have called it off.

+1

 

[StinkBug]

The only way to tell how much oil you have is to check the dip stick. A low oil pressure reading means it's already too late. The fact that you checked the dip stick and it showed under 6 quarts and there were signs of a major leak and you still decided to fly really worries me. It shows that either you're negligent or that you're ignorant. I don't say that to be mean, but because it's true. Either you willfully take risks one shouldn't, or you don't know enough to make the safe decision. This was a bad one that could have ended your life. Saying that there are fields within glide distance so it's ok is a pretty scary thing at night as well. I'd suggest discussing personal minimums with your CFI, as well as getting some education on basic engine mechanics.

 

[Stewartb]

So much drama. Nobody I know adds more than 6qts to a Lycoming because it'll puke anything more than that out the breather. Same with midsize TCMs.

 

[kenjr]

So much drama. Nobody I know adds more than 6qts to a Lycoming because it'll puke anything more than that out the breather. Same with midsize TCMs.

Depends on which one? We fly a 540 (Cherokee 235) and keep 9-10 in there and it'll spew a little after each flight but not enough that it wants to keep 6 quarts in there.

 

[Geico266]

So much drama. Nobody I know adds more than 6qts to a Lycoming because it'll puke anything more than that out the breather. Same with midsize TCMs.

That is just plain wrong. I don't have high oil usage and carry 7 qts in my IO-360 and 10 qts in my IO-540.

 

[Stewartb]

Wrong? That's what most guys do. All the guys I know for sure. At any rate the Lycoming engine operation manuals for 0-360 and 0-320 engines specify that the minimum safe oil quantity in the sump is 2 quarts. Just under 6 isn't reason for concern. If it used two quarts in a half hour previous to that most mechanics would say it was probably puking excess oil out and to go fly it at 6qts and see if consumption is back to normal.

 

[iflyvfr]

My 150 was like that. I only filled it full for a long flight (4+ hrs) and it puked oil right back to its own preferred level. My 172 is like that too, except for all the damn oil leaks from the aforementioned tubes and gaskets.

All this talk got me revved up and since it was almost 50* today, I went to the hangar this afternoon to see if my high oil consumption had a cause. I pulled the top cowl and could see oil on the right side, so I dropped the bottom half enough to get access to the valve cover.

Sure enough, there's oil drops on the bottom of the valve cover. Summoning my A&P, we pulled it and low and behold, look what we find. Valve gasket not installed carefully and probably overtorqued it and voila! Oil leak: https://drive.google.com/file/d/0BxRCx-rLC62NVGZqcFlpSVB2Y19mUHEwNm1kZ25ES3p2OXBN/view?usp=sharing

Here's a pic of the cylinder, on the upper left you can see the corresponding crud. Don't know if the oil burned, or what, but clearly there's a tale being told there: https://drive.google.com/file/d/0BxRCx-rLC62NZTUxaDBMc2hoeklwVUpPNDBVOHhyRXE1U1dr/view?usp=sharing

Put a new gasket on there, carefully reinstalled and hopefully leak is fixed.

 

[peerlesscowboy]

I put 7 quarts in my Lycoming O-360A1A, takes about 12 to 13 hours to drop down below six which I'd hardly call "puking" it out, add a quart to bring it back up to seven and I'm good to the 25 hr oil change

 

[Vaflier]

If the engine in this aircraft is a Continental and has had an oil filter adapter added to it with a spin on oil filter then the temps will likely read on the high side and right up to red line on a warm day. Adding the spin on adapter moves the temperature sensor back several inches and causes it to read higher. The original location has a blast tube blowing air on it causing it to read cooler than it actually is. Adding the adapter moves it back out of the air stream from the blast tube. Adding the spin on adapter does not change the actual oil temperature but it will change the reading to one that is more accurate. Cessna fooled the gauge with the blast tube.

 

[denverpilot]

Wouldn't have flown it.

That said, I've seen rentals covered in oil because the last guy flew it around with the oil cap off, and was too embarrassed to tell anyone, so they just landed, tried to clean up the mess, and poured enough in to make things look normal.

I've also done the oil cap trick to my own airplane once. And that's how I know you won't be getting it all cleaned up properly the first time. Haha. It's every freakin where. And I mean everywhere. It'll drip for a month.

The other thing that always seems to be a big no-no with rentals... You can't pull the cowl. Screw that.

Get the mechanic out there or just get it off with someone that knows what they're doing and LOOK and see where that crap is coming from. At least the top half of the cowl on most Cessnas. Piece of cake. Just get shown how.

Most rental places will probably lose their minds reading that. Which is why I own now. And truly hated the rental process.

You want me to fly this claptrap leaseback piece of junk covered in oil and I can't see where the hell this mess came from -- and you can't find a mechanic until tomorrow?

I'd be pulling the top cowl to look with their assistance to figure out where the bastard was leaking or I'd be extending my middle finger and letting them rent their garbage to someone else. My opinion. But then again it's my butt up in the air in the thing.

 

[N801BH]

I put 7 quarts in my Lycoming O-360A1A, takes about 12 to 13 hours to drop down below six which I'd hardly call "puking" it out, add a quart to bring it back up to seven and I'm good to the 25 hr oil change

Geez..... You poor aircooled guys/gals......

I change my oil every 50 hours... 5 Quarts of Amsoil 20 -50 racing stuff , 1 quart 70 weight Amsoil racing stuff, 1 pint of STP. I NAPA 51515 racing oil filter.... I lose less then 1/2 pint in 50 hours.....

I LOVE water cooled motors.....

 

[N801BH]

If the engine in this aircraft is a Continental and has had an oil filter adapter added to it with a spin on oil filter then the temps will likely read on the high side and right up to red line on a warm day. Adding the spin on adapter moves the temperature sensor back several inches and causes it to read higher. The original location has a blast tube blowing air on it causing it to read cooler than it actually is. Adding the adapter moves it back out of the air stream from the blast tube. Adding the spin on adapter does not change the actual oil temperature but it will change the reading to one that is more accurate. Cessna fooled the gauge with the blast tube.

A big thing I disagree with on certified planes /motors is.....

They install the oil temp sending unit AFTER the cooler and on the way back to the oil pump...

That gives a artificial reading.....

I want to know the ACTUAL oil temp the motor is putting out so my sending unit is the bottom of my oil pan...

You can see the location of my sending unit by the brazed fitting on the bottom of the oil pan just to the right of the high dollar FluidDamper harmonic balancer......

I HATE cold /cool/warm oil........My optimum temp is 220 -245f.....

Certified stuff will show 180-210 as on the high side and close to the red...

Truth is your oil is actually as hot if not hotter then my preference.... The cooler will shed 40-50f.... So when your gauges read 200.. the oil is REALLY 250 -260 in the motor.......

Another (smoke and mirrors) reading by the factory gauges.......

 

[yakdriver]

My Nanchang CJ 6 had both inlet and outlet temps on the engine. I should say has as I just bought another one last week. Don

 

[labbadabba]

I guess I should have posted this in the 'Lessons Learned' forum. LOL

Anyway, my suspicions were confirmed, a previous renter had left the oil cap off. And yes, this is the old Continental O-300 and according to the owner the gauge does indicate high oil temps.

I was at the airport the next day and someone ran down the battery on the starter, a lineman came out to jump the aircraft opened the oil door on the cowling to plug in the plane only to see it completely covered in oil and said "I'm not plugging anything into that."

I've had a lot of MX issues with our club rentals but I think this is the last straw for me.

And yes, this NOOB pilot learned his lesson. Thanks guys for making it clear that I did a dumb.

 

[petrolero]

Wouldn't have flown it.

That said, I've seen rentals covered in oil because the last guy flew it around with the oil cap off, and was too embarrassed to tell anyone, so they just landed, tried to clean up the mess, and poured enough in to make things look normal.

I've also done the oil cap trick to my own airplane once. And that's how I know you won't be getting it all cleaned up properly the first time. Haha. It's every freakin where. And I mean everywhere. It'll drip for a month.

The other thing that always seems to be a big no-no with rentals... You can't pull the cowl. Screw that.

Get the mechanic out there or just get it off with someone that knows what they're doing and LOOK and see where that crap is coming from. At least the top half of the cowl on most Cessnas. Piece of cake. Just get shown how.

Most rental places will probably lose their minds reading that. Which is why I own now. And truly hated the rental process.

You want me to fly this claptrap leaseback piece of junk covered in oil and I can't see where the hell this mess came from -- and you can't find a mechanic until tomorrow?

I'd be pulling the top cowl to look with their assistance to figure out where the bastard was leaking or I'd be extending my middle finger and letting them rent their garbage to someone else. My opinion. But then again it's my butt up in the air in the thing.

I rented from one infamous outfit at KAPA and had 3 failures out of 5 flights, one of which was full electrical in a Cessna Gutless, another was a vac failure - thankfully I was just doing T&Gs (not that I'd ever fly any of their turd birds in the clouds). The third failure was the primary Nav/Comm. And I hate renting on top of all that. I should have chosen Independence or Aspen, honestly.

And now I own. And since owning I've not had a sing... oh wait. OK but far less than often than those jalopies I once rented.

As for the OP, I will say that high oil temp in any airplane in cruise would be cause for landing. On climb in my TR182 with O-540, high oil temp in climb is a constant even with 9 quarts of goodness in there. Has to do with the way the oil cooler is installed. The oil temp determines my climb rate every #$%^&* time - even in winter.

 

[denverpilot]

I rented from one infamous outfit at KAPA and had 3 failures out of 5 flights, one of which was full electrical in a Cessna Gutless, another was a vac failure - thankfully I was just doing T&Gs (not that I'd ever fly any of their turd birds in the clouds). The third failure was the primary Nav/Comm. And I hate renting on top of all that. I should have chosen Independence or Aspen, honestly.

Haha. That narrows it down. That's one beat up Gutless.

Of course... they all are around here. That's the problem with doing a Commercial rating at any of the clubs around here. The retracts are flown hard and put away wet. There isn't a good quality one to be rented without joining a non-commercial club for 500 miles around.

Twins too. But at least most of the twins are hangarss or under a t-hangar shelter to keep them from being destroyed by hail.

 

[MAKG1]

The presence of oil isn't necessarily an indication of un-airworthiness. Some airplanes leak oil. Pressure cowls make it go everywhere.

Oil that had STREAMED is indeed an indication of unairworthiness. That is not normal.

Drips are normal. This is more than a drip.

Now someone might have severely overfilled the crankcase, but you want that proven under the circumstances.