Low Oil Temp

Pilot-To-Be

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Piper Cherokee 180 has low oil temp in the winter months. We don’t have a winterization plate and the owner doesn’t want to use aluminum tape.

What are the risks if any of flying in cold weather with low oil temps? (120f or so). We use an oil pan pre heater but that’s all.

Thanks
 
I would think your oil would retain a lot of moisture - not hot enough to dissipate it.
 
Piper Cherokee 180 has low oil temp in the winter months. We don’t have a winterization plate and the owner doesn’t want to use aluminum tape.

What are the risks if any of flying in cold weather with low oil temps? (120f or so). We use an oil pan pre heater but that’s all.

Thanks
The oil pan heater is ok for preheat but not during flight. You can make a winterization plate, it's legal under whatever that appendix is. Just need tin snips and some aluminum sheet. See if there's an EAA chapter in the area and ask for help and or some scrap aluminum. I created one many years ago and it definitely helps. Altho there's 4 screw holes in the oil cooler, I only attach the plate with the top 2 screws. I would never use the tape. This weekend, even with the plate on, the oil in my cherokee 180 barely made it to 160 after 30 min of flying. Denver, 2 pm, air temps on the ground were in the high40s/low 50s, at altitude (8500 msl) it was close to 0F. Here's a drawing, I didn't bother with the slots on the bottom, I just did a square that covered the oil cooler hole. Note the hole in the middle.

winterization-plate.jpg
 
"The desired oil temperature range for Lycoming engines is from 165˚ to 220˚ F. If the aircraft has a winterization kit, it should be installed when operating in outside air temperatures (OAT) that are below the 40˚ to 45˚ F range."

 
Piper Cherokee 180 has low oil temp in the winter months. We don’t have a winterization plate and the owner doesn’t want to use aluminum tape.

What are the risks if any of flying in cold weather with low oil temps? (120f or so). We use an oil pan pre heater but that’s all.

Thanks
why not get one?
 
What's the problem with aluminum tape?

Over in the Bonanza world, most of us cover 50% or so of the oil cooler with aluminum tape. It comes off easily in the spring. There is actually more concern over winter baffles there - the story being that one should not disturb or change the flow of cooling air through the engine compartment.

- Martin
 
What's the problem with aluminum tape?

Over in the Bonanza world, most of us cover 50% or so of the oil cooler with aluminum tape. It comes off easily in the spring. There is actually more concern over winter baffles there - the story being that one should not disturb or change the flow of cooling air through the engine compartment.

- Martin
Airplane owner sets the rules.
 
Airplane owner sets the rules.
Yes, of course.

But that is really not an answer to the question I asked; so I'll ask again: What is the (perceived or real) problem with using aluminum tape on the oil cooler?
 
Yes, of course.

But that is really not an answer to the question I asked; so I'll ask again: What is the (perceived or real) problem with using aluminum tape on the oil cooler?
Tape has been known to come loose and cause problems. Aluminum tape could short something electrical. Any tape could get sucked into the carb heat air inlet and hit the muffler and start smoking. I had that happen with polyurethane anti-chafe tape from the inside of the cowling where the baffle seals chafe on it. That tape made a bunch of scary smoke that forced the pilot to land as soon as he could.
 
If raining oil temp is the goal? Tape on the oil cooler is the best solution. Cold weather doesn’t affect CHTs much so blocking air to the cylinders isn’t necessary in most cases. I tape my oil cooler all year round.
 
What are the risks if any of flying in cold weather with low oil temps? (120f or so).
Water vapor is a byproduct of combustion. A gallon of gasoline can create a gallon and a half of water, most of it going out the exhaust, but some will get past the rings and into the crankcase when the engine is cold, and it condenses in there. After the oil warms up, the heat will evaporate that water and it will be driven out of the breather.

A cold-running engine doesn't get rid of that water. The water mixes with the oil, and after shutdown and while the airplane sits for days or weeks the oil/water mix turns into several different acids in the presence of catalyzing metals. Those acids then eat that engine from the inside out. Rusty cam and lifters. Pitted cylinders and pistons and rings. Pitted valve stems that can then break. Rusty accessory case gearing. Pitted magneto impulse springs that break and take that mag to near zero TDC, and if that magneto happens to be one of those Bendix dual mags, both mags go to zero TDC and the engine pretty much ups and dies on you. It is all very ugly and expensive and sometimes dangerous.
 
Air pressure and physics are your friend. One sticks the aluminum tape on the INLET side of the oil cooler.
 
Tape has been known to come loose and cause problems. Aluminum tape could short something electrical. Any tape could get sucked into the carb heat air inlet and hit the muffler and start smoking. I had that happen with polyurethane anti-chafe tape from the inside of the cowling where the baffle seals chafe on it. That tape made a bunch of scary smoke that forced the pilot to land as soon as he could.
Utter nonsense in most cases with tape on the INTAKE side of the oil cooler. I suppose they may be oil cooler installations where this could be some risk, but most oil coolers I've seen would have no meaningful risk from properly and carefully applied tape. These kind of hysterical fears shouldn't be perpetuated.
 
O-320D, NA. AL tape on the intake side of the oil cooler here. To foul anything meaningful would require first coming loose (not likely given my experience in taking it off) and then working its way forward and outside the engine baffles. It's pretty effective and absolutely necessary in the winter. I'm comfortable with the risks.

Nauga,
toasty
 
Engine temperature management is the pilot’s responsibility.

I’ve used cloth tape and foil tape on oil coolers for 30 years with no problems. I tried a Cessna winter front and landed to remove it after 30 minutes. I never used it again.

My exp Cub has outlet ducts with pilot-controlled butterfly valves on dual oil coolers. Controlling out flow works well, too, but tape sticks better on the front side.
 

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I tried a Cessna winter front and landed to remove it after 30 minutes.
Same here. Placard says below 20 F. Tried at 10 F once (at the surface) and landed to remove. Pretty sure at -5 F they might be workable.
 
In my experience, fabric tape can leave a residue. Aluminum tape does not.
 
My mechanic put a butterfly valve in the oil cooler housing with a control knob in the cockpit. Now I can vary the amount of air getting to the oil cooler to keep the oil temperature in the sweet spot. I typically shoot for 180 degrees and I'm able to hit that target any time of year without resorting to tape or covers that (in my case) would require pulling the cowling off to adjust.
 
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