alaskan9974
Pre-takeoff checklist
Oil temp is running low in cruise in winter, taped cooler on my bonanza and 182 to get them into the green in cruise but the pa-32 is cowled a little better, what oil temp should I try for, 140-180?
Oil temp how low is too low
- Thread starter alaskan9974
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BillTIZ
Final Approach
Be careful using tape. Air pressure against the oil cooler can push the tape into the fine holes in the radiator style cooler and block airflow in the summer when you really need the cooling. It's a b**ch to clean. Most manufactures have a metal plate for a "winterization kit".
Normally temperatures need to be above 180F for 30min to boil the moisture contaminants out of the oil. It's hard to get that high a temp in winter. I saw 160F two weeks ago on the Pawnee O-540 on a warm early winter day, about 40F OAT.
Normally temperatures need to be above 180F for 30min to boil the moisture contaminants out of the oil. It's hard to get that high a temp in winter. I saw 160F two weeks ago on the Pawnee O-540 on a warm early winter day, about 40F OAT.
alaskan9974
Pre-takeoff checklist
I use aluminum foil tape it doesn’t seem to break, my oil temps are just above green in cruise, 90-100
BillTIZ
Final Approach
someone in the club put the foil "furnace tape" on an oil cooler once.. we made him spend the next 3 hours clearing it out of the holes after his 6hr cross country.
Gary Ward
En-Route
455 Bravo Uniform
Final Approach
It’s going to depend on where your temperature probe is located in the oil system.
Gary Ward
En-Route
I use these block offs in the cowl of a 172 only when it get's really cold down around 10°F. My oil temps run pretty steady even in the cold weather so I don't worry about until it get's really cold.
In my case if I tape off the oil cooler then it forces more air down through the engine. I also tape off the fresh air intake openings in the wing to help keep the cold air out of the cabin.
In my case if I tape off the oil cooler then it forces more air down through the engine. I also tape off the fresh air intake openings in the wing to help keep the cold air out of the cabin.
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Dan Thomas
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The TCDS for just about any engine or airplane list the redline oil inlet temperature. Pretty hard to do that if the probe is just any old place. It's usually somewhere just downstream of the oil cooler return line.
Gary Ward
En-Route
Like I said my oil temps don't seem to be effected much by cold air? This day the OAT was 7°F and my hi tech( joke) oil temp gauge shows where it always does year round. Pretty sure I don't have those block offs in for this picture. I worry more about the pilot staying warm verses the engine.
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Domenick
I've used aluminum foil tape in the winter on my oil cooler for 20 years. Never a problem.
It is NOT fabric duct/duck tape which leaves a sticky residue.
Nashua Tape 1.89 in. x 50 yd. 322 Multi-Purpose HVAC Foil Sealer Duct Tape 1906075 - The Home Depot
This Nashua Tape Multi-Purpose HVAC Foil Tape is designed for taping joints, seams against moisture and vapor on foil jacket insulation.
www.homedepot.com
Stewartb
Final Approach
Continentals will have cooler oil temps than Lycomings. My Cub has adjustable oil cooler ducts but I leave them open even in cool temps. My 180 needs tape year round. I use one full strip in summer and nearly 100% coverage in winter. In either case my oil temp in the Cessna shows about 165°. If it didn’t register at >150° even on a cold day, I’d take action. Remember, 70° is the minimum oil temp for a big Continental. You shouldn’t be applying power below that minimum.
Aluminum tape works great but fabric duct tape has never caused me any grief. I’ve taped my oil coolers for 30 years with no issues. Usually with fabric tape.
Aluminum tape works great but fabric duct tape has never caused me any grief. I’ve taped my oil coolers for 30 years with no issues. Usually with fabric tape.
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Dan Thomas
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I think there is some law about that. Can't remember where. Some one here in Canada got into some difficulty with the feds. They saw it as an unapproved modification or something. A taped-off vent can present serious difficulty if your carbon monoxide detector tells you that you're about to die if you don't get some fresh air into the cabin. Or if you get a fire of any sort that requires discharging the extinguisher in the cabin. That fills the air with obscuring dust. Smoke from the fire also blinds the pilot. Electrical fires in small airplanes are not rare. Check the landing/taxi light switches in your 172; they are famous for melting down and burning up under the higher current loads. Your LED lights go a long way toward avoiding that. An incipient problem can be spotted by noting discolored insulation on the wire crimp terminals on the switch. It starts to get dark.
Those Cessna vents are indeed leaky. I installed several sets of these for customers:
https://www.aircraftspruce.com/catalog/appages/ventube.php?clickkey=3080433
schmookeeg
En-Route
Did they speed-tape the windows shut too?
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Hang 4
Never, ever have a dry chemical fire extinguisher in an airplane. It's a sure way to be in IMC regardless of weather.
alaskan9974
Pre-takeoff checklist
I found a set for 301 pa-32's but none around that I saw for the PA-32 cherokee I have, will just stick to tape until I find something correct for it. Should I shoot for midrange on the gauge? The oil temp struggles to stay above 120 when its warm around 0f, but is lucky to get above 100* when oat reaches -30 and colder.
160F is fine, 180F is better. I wouldn’t want it any higher.
There used to be a guy who sold metal plugs to cap off those inlets. Worked pretty good from what I remember. But don't recall anymore than that.
Daleandee
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IMHO 160ºF is too cold. 180-220ºF is where oil should run. From Blackstone labs: "We measure the viscosity at 210°F, which is in the neighborhood of your engine oil at operating temperature at cruise." https://www.blackstone-labs.com/about-aircraft-oils-2/
Flying today in 56ºF OAT my cruise oil temp was 179ºF which, to me, is not warm enough.
To each their own ...
Edit: https://www.eaa.org/eaa/news-and-pu...-2017-control-of-your-engines-oil-temperature
Religion is controversial, but I feel perfectly comfortable with 160F assuming it’s flown long enough. Temperature matters less than frequency and duration of operation.
Daleandee
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Flying often is a key factor but there is adequate proof that less than 180ºF can be the cause of water retention which leads to cam rust and other issues. Oil is a much better lubricant being a little too warm as opposed to being a little too cold.
If 160 is works for you that's great. I have no beef with how you operate your airplane but wanted to point out that the recommendation for aircooled aircraft oil temp is a higher number.
"Keeping an engine too cool in flight can also be harmful; if oil cannot get hot enough to burn off water that has condensed in it, internal engine rust can occur. Engine experts suggest an oil temperature of around 180 degrees or a little higher as a happy medium for typical air-cooled GA engines."
FWIW ...
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Dan Thomas
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Why don't we see what an engine manufacturer says about it? From Lycoming's O/IO-360 Operator's Manual:
https://www.lycoming.com/sites/defa...0%26%20TIO-360%20Oper%20Manual%2060297-12.pdf
https://www.lycoming.com/sites/defa...0%26%20TIO-360%20Oper%20Manual%2060297-12.pdf
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Not sure if all pa32s have their oil coolers in the same place, but on the lance they are in the back and too cool has never been a problem. My engine monitor alarms at 215, and it's not uncommon to see that in the summer, but as Dan posted, that's still a ways below redline. I see 180-190+ on cold days.
Interesting side note, I flew @masloki to Minnesota last winter on a crisp -20C day. I was alarmed when the oil temp alert starting flashing...215...216...217.... then it eventually dropped pretty fast back to normal range. A few minutes later it did it again. I think at that temperature the vernatherm was so cold it was shutting down the flow to the coolers, and the engine had to get pretty hot to open it again. Everything else was normal other than that cycle repeating. I'd think twice before flying in those temperatures again though. That's the only time I've ever had to put the cabin heat to its highest setting.
Interesting side note, I flew @masloki to Minnesota last winter on a crisp -20C day. I was alarmed when the oil temp alert starting flashing...215...216...217.... then it eventually dropped pretty fast back to normal range. A few minutes later it did it again. I think at that temperature the vernatherm was so cold it was shutting down the flow to the coolers, and the engine had to get pretty hot to open it again. Everything else was normal other than that cycle repeating. I'd think twice before flying in those temperatures again though. That's the only time I've ever had to put the cabin heat to its highest setting.
baboss
Line Up and Wait
They were made by SAIR Corp and they are nice. He made lots of nice stuff but no longer in business.
Can be seen here: https://backcountrypilot.org/forum/cessna-vent-covers-they-actually-work-20350
And here
SairCorp/Flight Boss Ltd :: Vent Covers, Cessna
Welcome to SairCorp/Flight Boss Ltd We specialize in Safety and Convenience products designed for Pilots by Pilots. High Quality durable products with World Class Customer Service. Enhance Fight Safety and Comfort with our Aviation Products. Organizer Consoles Organizer Accessories...
web.archive.org
I run them all winter as my vents are leaky, which is just another project on the list.
Ed Haywood
En-Route
Have heard that stated many times as an established fact. But I wonder whether there is any science or test data to support it, or if it is just a useful rule of thumb that has been repeated so often it has become truthy.
455 Bravo Uniform
Final Approach
Somewhere in the engine crankcase, the temperature is way way high enough to boil water. Underside of the pistons, piston pins, along the top part of the rod, along the cylinders, valve stems, etc. Oil touches those parts and starts to cool down as it falls and drains away to the sump and pickup to be pressurized by the pump and sent to the cooler before heading to do pressurized duty, then to repeat the spray/splash/drain. The only temperature we “see” is where the probe is located (and where the Mfg gives their limits).
Daleandee
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They don't give science or test data in the article but there's good information here from a guy that might know a bit about oil. From the article:
Paul speaks of the importance flying often as RyanB mentioned earlier and the article also has this:
Dan Thomas listed some Lycoming data earlier showing the desired temp to be mostly 180-245ºF (although I think 245 is too hot). I'm confident that Lycoming did the research on this but for me this has been a rule of thumb as so many credible sources have used it. Others are free to set their own operating limits for the aircraft they operate. If what you are doing is working, stay with it ...
Gary Ward
En-Route
I wonder if it would be more legal if I used FAA-PMAA approved duct tape in instead of 3M?
Like said both of my windows open and the air vent in the side of the fuselage works.
Plus I got one of those 6 dollar things on my panel that I never look at that turns dark if CO is present.
Wiring melting down? your freaking me out.
This was the first thing I did when I got my plane was put these aluminum eye ball vents in with my mechanics blessing. Because the flight school 172S models, the plastic ones were broke and leaked air. My wife hated that so I did this. They seal pretty good but I still like to tape off the wings. Not sure if it is legal but does help a little.
140 dollar vents and 4 dollars of PVC pipe. Heat the PVC a little and the aluminum eye ball vent screwed in.
Dan Thomas
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Now, I am no physicist, but water doesn't need to get to boiling to evaporate. Its vapor pressure rises dramatically with temperature, like so:
Look how much higher that pressure is at 100°C (212°F) than it is at 60°C (140°F). You want that temperature up to get the water evaporating so it's driven out of the crankcase vent.
That there, but really low oil temps aren't helping.
One thing that every owner should have done is a check of the accuracy of the oil temp gauge. I did it regularly in suspect cases. It's not hard to do.
Not really. The data for Aeroshell 15W50, for example, shows a flashpoint (gives off flammable vapors) of 238°C (460°F). The oil is starting to coke then, forming carbon deposits everywhere. Its viscosity also gets too low at elevated temperatures and it doesn't lubricate well when it's so thin, and can't cool well. It's all why we have oil coolers.
Oil temps that get beyond redline are shortening the life of the oil.
It happens. I have had old switches melting. The switch contacts oxidize, introducing resistance and therefore heat is generated. The crimp terminals and the wire inside them oxidize, too, and they can get hot and that heat travels through the switch terminals into the switch. It's one reason why Cessna now wants the landing, taxi and master switches replaced every four years or so.
https://www.tsb-bst.gc.ca/eng/rapports-reports/aviation/2007/a07o0264/a07o0264.html
Gary Ward
En-Route
Oh man, stop it with the replacement ideas!!
Dan Thomas
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It's not bad if all the sketchy stuff is fixed; keeping it up-to-date means small inspections and repairs here and there instead of that first-annual shocker that the next owner faces. Our fleet's maintenance costs were not bad at all, but when we bought another airplane we went through it and fixed everything. That meant an airplane that didn't let down the students, especially far from home. And it made life easier for me in the long run.
chemgeek
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The vernatherm in my AA-5 seems to maintain these temperatures perfectly: 180F above 0C and not under 170F below 0C.
Ed Haywood
En-Route
My personal policy prior to my recent restoration was to replace any hardware and standard parts that I touched during a maintenance process. Not that it was necessary, but I just figured why reuse 45 year old stuff if you have a new one handy. That was especially the case for switches, breakers, etc. One less thing to have an issue with.
Ed Haywood
En-Route
I have two OT sensors. Primary on the pressure screen housing, and alternate on a port on the front of the case. The alternate consistently reads 15 degrees higher than the primary.
alaskan9974
Pre-takeoff checklist
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Richard Digits
How confident are you in that guage?
alaskan9974
Pre-takeoff checklist
Seemed to work fine in the summer, this was at -40 oat on landing.
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Richard Digits
If the oil is actually that cold I'd be suspicious of the vernatherm. That said, when my oil is that cold my oil pressure is up in the hundreds. Also, the oil temp will get over 100 just idling after startup, even on the coldest days.