Lycoming 0-320 White- Yellowish Goo On Bottom of Oil Dipstick

Mooney Fan

Mooney Fan

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Mooney Fan
It has been pretty cold here in Southwestern KY, 15 degrees this morning. I was at the hangar to plug in my Tannis Heater before daybreak. Checked the oil and there was this white, yellowish like goo mixed in with the oil on the bottom of the dipstick. Nothing large but I have never seen that before. Is this water that would eventually get boiled out during flight?
 
Water emulsifies with oil and makes the gooey froth. It was likely on the top so your dipstick grabbed it on the way up. Whether it's too much? I'd be alarmed to see any in that situation.
 
Stewartb said:
Water emulsifies with oil and makes the gooey froth. It was likely on the top so your dipstick grabbed it on the way up. Whether it's too much? I'd be alarmed to see any in that situation.
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Agreed. My past (2) oil analysis from Blackstone had no issues with water. First report said no water found, second report no fuel, water or dirt excess found.
 
I’d be changing that oil and checking to see that the oil temp is reaching at least 165F during during winter operation. Engine gauge indications are no good for this.
 
Clip4 said:
I’d be changing that oil and checking to see that the oil temp is reaching at least 165F during during winter operation. Engine gauge indications are no good for this.
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Thanks. Any suggestions on how to check the temp?

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Personally, I wouldn't worry too much about it unless it is really bad. Water/moisture is a byproduct of combustion and naturally ends up in the crankcase. I'd just go fly and monitor it, and also make sure your engine is running warm enough.
 
mondtster said:
Personally, I wouldn't worry too much about it unless it is really bad. Water/moisture is a byproduct of combustion and naturally ends up in the crankcase. I'd just go fly and monitor it, and also make sure your engine is running warm enough.
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Thanks. She is cold natured. Even in August 180 degrees is about it. I have a winter plate but thinking of adding some duct tape to block off the rest of the oil cooler
 
Mooney Fan said:
Thanks. She is cold natured. Even in August 180 degrees is about it. I have a winter plate but thinking of adding some duct tape to block off the rest of the oil cooler
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What is the outside air temperature in August when you're seeing 180 degree temperatures? Do you believe the temperature indication you're getting is correct? If it is always "cold natured" it might be that the temperature indication is a bit lower than reality.

This is also something I wouldn't get paranoid over but might be something you want to investigate before blocking off more of the oil cooler than what the factory plate does.
 
Do you have an oil separator on that engine?
 
4F2C1A80-61D1-45E1-BE17-4A057F4B262C.jpeg I went flying today. I like to keep inactive periods under 2 weeks, ideally <10 days.

I plugged in the Reiff yesterday, with a blanket. I did a space heater inside the cabin while I was shoveling, then some preflight checks. I flew for 30 minutes, oil temps up to 180 with my homemade winterization plate.

The only issue was trying to get the plane back in the rental hangar, as expected. I fired up the gas tug, my kitty litter wasn’t enough traction. Since it was still about 4 below, not many others hanging around, only needed a slight amount of extra push. I was able to track down assistance and got the plane pushed in.

I’m almost due for an oil change. I’d like to have at least 30 degrees for that.
 
mondtster said:
What is the outside air temperature in August when you're seeing 180 degree temperatures? Do you believe the temperature indication you're getting is correct? If it is always "cold natured" it might be that the temperature indication is a bit lower than reality.

This is also something I wouldn't get paranoid over but might be something you want to investigate before blocking off more of the oil cooler than what the factory plate does.
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Probably 75/80's at the altitudes I fly. I have only seen it over 180 one time. Leaning helps. It goes in for Annual in April and I will have the gauge checked out
 
Mooney Fan said:
Thanks. Any suggestions on how to check the temp?

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Shell Oil used to have a publication on this. What I recall they suggested was pulling the oil tempeture sender and placing it in heated oil with a thermometer. When the oil reached the desired temperature, to mark the gauge at the appropriate indication in the plane.

On aircraft with cowl flaps, closed during climb before cruise will help the oil get hot and proper leaning helps. Otherwise the oil never gets hot. You may also need a winterization kit.

IMO, what you describe on your oil is an invitation for an early cam replacement.
 
Mooney Fan said:
I don't know. Not even sure what it does :rolleyes:
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An aircraft engine has an oil breather line that exhausts vapor consisting of air, oil mist, and combustion byproducts from the crankcase. A wet vacuum pump also vents air and oil mist. A dirty aircraft belly is often the result. An oil separater is a component designed to separate the oil from the air in this exhaust, and return the oil to the case while letting the air vent overboard. If you have a wet (oil lubricated) vacuum pump, you'll almost assuredly have an oil separater plumbed into the pump outlet. If you have a dry vacuum pump, you may have an oil separater plumbed into the breather line--it helps keep the belly clean but its downside is it also returns the combustion byproducts back into the engine instead of overboard.
 
Mooney Fan said:
Probably 75/80's at the altitudes I fly. I have only seen it over 180 one time. Leaning helps. It goes in for Annual in April and I will have the gauge checked out
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That's probably not too far off from where it should be at those temperatures. If the engine has a thermostatic oil cooler bypass (vernatherm) they are set at 85C, which would be about 185F. It may run up to that point and just kind of stop if the cooling is adequate to keep temps in that range.

I probably wouldn't have your mechanic check the temperature indication unless you really suspect there is a problem. I'm not convinced there is right now.
 
sourdough44 said:
I flew for 30 minutes, oil temps up to 180 with my homemade winterization plate.
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And there's the problem. Sure, the oil temp comes up, but you need both temperature and time to get rid of the water in the case. Lower temps need more time. Short flights cause the water to accumulate and it just gets worse. Ground running is the worst thing. Even in the summer you can get plenty of moisture in the case.

It's not just camshafts that suffer. Cylinder walls get pitted. Gears rust. Lost of stuff corrodes.
 
My Archer with an o-360 came with a winterization kit which is just a plate that blocks the airflow into the oil cooler. It helps keep the temps up in very cold weather.
 
If it has an oil separator, I believe they have a tendency to hold moisture in the crankcase, along with the recycled oil?
 
I've got 1/2 my cooler blocked off on my O-320 and the oil temp is in the yellow most of the time. RPM is 2500 and I normally fly for at least an hour. Even in the summer oil temp just touches the bottom of the green arc. Gauge is not numbered just red, green and yellow. The POH states the ranges but it's in the hanger right now, so I can't reference.

Reading this thread makes me think it might be a good idea to check the system as @Clip4 suggests
 
Calibrating an analog oil gauge is a good idea. Ansoupmcan of oil, a burner to heat it, and an accurate thermometer, put the sender in and check the gauge at known temp values. The hard part is the sender needs to be grounded to the aircraft, so figure that out first.
 
Dan Thomas said:
And there's the problem. Sure, the oil temp comes up, but you need both temperature and time to get rid of the water in the case. Lower temps need more time. Short flights cause the water to accumulate and it just gets worse. Ground running is the worst thing. Even in the summer you can get plenty of moisture in the case.

It's not just camshafts that suffer. Cylinder walls get pitted. Gears rust. Lost of stuff corrodes.
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Think of it as a pot of water on the stove. Yes,you can get it up to boiling pretty quickly, but if you turn the heat off, you still have water. IF you let it boil longer (eg: 30 minutes), voi-la, the water is gone. That is what you want to do with your engine. Run it for at least 30 minutes AFTER it gets hot. And if it only gets to 180 (as opposed to 200+) then you might need to run it longer.

(this explanation is for illustration only; others may chime in with better timing/temperature ranges).
 
I usually cruise at 2450 depending on the flight objective. Maybe I should think about 2500rpm and lean it some, regardless of altitude
 
Cold air usually does the leaning for you.

Engine temperature management is the pilot's responsibility. That isn't limited to keeping it cool. Sometimes we need to take steps to keep it warm. Duct tape on the oil cooler is a very useful tool for winter flying. My old 0-320 required 100% of the cooler to be covered during winter.
 
Do you have any recommendations for the o-200? I have noticed that it is difficult to get the oil temp up in cold weather. What and where would be best to tape up to warm it up?
 
Matthew Rogers said:
Do you have any recommendations for the o-200? I have noticed that it is difficult to get the oil temp up in cold weather. What and where would be best to tape up to warm it up?
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You'd need more than tape for that engine. There were oil tank cover kits available for the small Continentals but I can't find them anymore. Maybe nobody makes them now. They were a fabric blanket that had snaps; you wrapped it around the tank and snapped it together.

There's usually a baffle channel along the lower crankcase seam. It takes air from just under the crankshaft's flange and directs it along the case and to the oil tank. That's an O-200's oil cooler. If you could find a way to close off that channel the oil would warm up.
 
Dan Thomas said:
You'd need more than tape for that engine. There were oil tank cover kits available for the small Continentals but I can't find them anymore. Maybe nobody makes them now. They were a fabric blanket that had snaps; you wrapped it around the tank and snapped it together.
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Last one I bought was a couple of years ago from Wag Aero. No idea if they’re still selling them.
 
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