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Minimum Oil Temp Required

D

dtaylor

Member
I am hearing that at least 180 degree F oil temp is required for at least 1/2 hour of engine operation to burn off all the water in your oil.

Is this true?

How important is this year around?

If I can only run my engine in the winter at 160 deg F max, will I build up water in my engine oil and cause corrosion?

Dave T.
 
It is important, you can install a shutter from Van?s or just tape off half or so of your oil cooler in the winter. If it where mine I would do one of these to get the temp up over 180F.
 
Time and Temperature

No hard fast rules. There is always water in the oil, the only question is how much. No magic temperature for the oil, but if the oil temperature is below the dew point of the exhaust blow by, you will be adding water to the oil. If it is above, you will be removing water. I am not sure of the dew point of exhaust gas, but I recall it being in the neighborhood of 140F.

Perhaps others more knowledgeable of this value will chime in. The larger the temperature spread between the exhaust dew point and the oil temperature, the faster the reduction.
 
AlexPeterson said:
No hard fast rules. There is always water in the oil, the only question is how much. No magic temperature for the oil, but if the oil temperature is below the dew point of the exhaust blow by, you will be adding water to the oil. If it is above, you will be removing water. I am not sure of the dew point of exhaust gas, but I recall it being in the neighborhood of 140F.

Perhaps others more knowledgeable of this value will chime in. The larger the temperature spread between the exhaust dew point and the oil temperature, the faster the reduction.
Click to expand...

Just yesterday I changed my oil after doing some formation flying with some friends. I normally tape over the oil cooler in the wintertime to keep the oil temps up, but didn't get around to doing it until yesterday. For the duration of the flight, the oil temp was no hotter than 165F. I cut the filter to inspect it, and was surprised to find little silver looking things floating around in the oil. I use automotive filters and they have an anti-drainback valve, so there's a pint or better that stays trapped in the filter. The little silver things turned out to be droplets of water.
 
YES...YES...

If you're flying a Lycoming engine, no less than 180 for at least 30 minutes, Twice a month!!
 
Maximum Service Life

For max. life, the Lycoming manuals suggest oil temp at cruise to be 165 to 220 Fahrenheit.
 
you may not get there

I usually tape off the front side of my baffle mounted oil cooler around Thanksgiving. The plane lives in a warmed (60F-ish) hangar. It was 15 degrees here in northern Utah and we decided to fly put for lunch. My oil temp never got above 160, probably closer to 150 (bottom of the green arc).
That's how it is. I've got a cool running engine. Summer oil temps rarely get above 190.
 
About to tape off my oil cooler. Was wondering what type of tape folks use.
Doesn't the heat of the engine and oil cooler melt the glue of the tape and cause it to slip off? I was considering using aluminum foil tape. Do you just tape off the front of teh baffle where the opening is behind the #4 cyliinder? Does anyone tape around the back of the oil cooler?
Any photos would really be appreciated!

Peter K
9A-99 hrs
 
Peter,

I installed a door on my cooler, operable from the cabin.

Tape on the back side will likely blow off. I've heard folks using duct tape or the like for the front side, but Al tape should work as well.

greg
 
Steve said:
I usually tape off the front side of my baffle mounted oil cooler around Thanksgiving. The plane lives in a warmed (60F-ish) hangar. It was 15 degrees here in northern Utah and we decided to fly put for lunch. My oil temp never got above 160, probably closer to 150 (bottom of the green arc).
That's how it is. I've got a cool running engine. Summer oil temps rarely get above 190.
Click to expand...

Last week on a different thread, I posted the results from installing the Van's shutter on the front side of the cooler, between it and the #4 baffle. It's cable operated from the panel.

Two weeks ago, on a flight from South Valley Regional (U42 ....previously known as Airport #2) to Jackpot, Nevada with temps ranging from 25 to 31F, I was able to maintain 185-195 F. the majority of the time. On a quick climb to 10,500 it reached 220F with the baffle fully closed.

I consider the baffle a success, but of course it wasn't tested at 15F. I'm interested if it's going to effect summer temps. I doubt it will be much different, even though the baffle closes off some of the open area, but still has more open area when you deduct the fin area of the oil cooler.

BTW--- for anyone installing a Van's baffle, there must be a washer or two between the cooler and baffle. The cooler fins will push against the slider parts of the baffle if you don't, when the bolts are properly torqued. Use some weather stripping or RTV to fill the gap. The washers also allow additional airflow around the fixed part of the shutter. This unit must be installed on the front of the cooler. It's not nearly effective when installed on the backside.

L.Adamson --- RV6A

And P.S. --- I used the metal duct tape previously. Goes on and comes off easily.
 
Simple metal oil cooler block

I cut a pcs of light wt aluminum scrap that would cover half of the oil cooler vertically. I drilled holes to match the bolt holes on the outboard side of the cooler. I remove the outboard bolts and slip in the sheet of aluminum. The existing mounting bolts hold it in place.
 
dtaylor said:
I am hearing that at least 180 degree F oil temp is required for at least 1/2 hour of engine operation to burn off all the water in your oil.

Is this true?

How important is this year around?

If I can only run my engine in the winter at 160 deg F max, will I build up water in my engine oil and cause corrosion?

Dave T.
Click to expand...


"The heat is on: Our experts agree on the best oil temperature" by Ben Visser
http://www.reiffpreheat.com/Article-Visser3.htm

Engine Preservation for Active and Stored Aircraft
http://www.reiffpreheat.com/Lycoming SL180B.pdf
 
RocketBob,
Did I read your post correctly? You're using Napa Gold 1515 oil filters on your Lycoming? Do they have the female thread (CH48108) or the male spud (CH48103)? They probably don't have the safety wire tabs either, right?
No wonder the global warming trend has reversed itself.
 
Steve said:
RocketBob,
Did I read your post correctly? You're using Napa Gold 1515 oil filters on your Lycoming? Do they have the female thread (CH48108) or the male spud (CH48103)? They probably don't have the safety wire tabs either, right?
No wonder the global warming trend has reversed itself.
Click to expand...

Yep.

Just remove the nipple off of a Champion filter, and permanently mount it in the oil filter housing with some red loctite. I cut some of the thread off on the lathe to shorten the nipple because there's really no point in having much more than needed to engage the filter threads. Having the long thread just helps in creating a mess when changing the filter. No safety wire, never understood the point of having it...if its loose enough to spin its already going to be leaking profusely. Been using Napa Gold filters for over 1000 hours now, and have several friends doing the same. 1515 is longer than a Champion, thus having more filter area and less pressure drop. 1068 also works well, is shorter than the 1515.

For the price of one Champion filter I buy four 1515's, and there's nothing inferior about them. The can is thicker on a Champion, and no nut.
 
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I put an Anti-Splat shutter with cable on mine (looks similar or the same as the one Van's sells). I didn't want to mess around with taping/untaping, and wanted the flexibility of in-cockpit control to conveniently accommodate the widely variable ambient temps we often see in this area, particularly in the fall and spring. On a 45 degree day with the shutter fully closed I was able to get over 200°F and on the same flight fully open it ran about 145°.
 
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avi8tor50 said:
About to tape off my oil cooler. Was wondering what type of tape folks use.
Doesn't the heat of the engine and oil cooler melt the glue of the tape and cause it to slip off? I was considering using aluminum foil tape. Do you just tape off the front of teh baffle where the opening is behind the #4 cyliinder? Does anyone tape around the back of the oil cooler?
Any photos would really be appreciated!

Peter K
9A-99 hrs
Click to expand...

3M Aluminum Tape. Its temp rating is something like 248deg.F Seems to hold up just fine for a season. While the cylinder may be +- 350deg.F, that's the cylinder body at location of the sensor. With all of that plenum air, I doubt the tape sees much heat. I will have to put my temp. gauge on it and take a flight and see.

Yes, tape to the front of the cooler behind cyl #4.
I ended up taping up most of the cooler keeping about 1" clear on the bottom but it really depends on where you are flying.

I had the Van's shutter and it worked well on the back side of the cooler. I couldn't mount it on the front side without major surgery. At that, I still had to modify the shutter flanges as my cooler ended up too close to the engine mount so I had to do some mods for mounting. Had I installed it during the build, it would have gone on the front.

Vans oil cooler Shutter self destructed at about 850 hours. The control arm engages into the shutter panes with small steel pins. The steel pins eventually chewed through the thin aluminum panes, I believe do to vibration as they operated easily and smoothly. I bought a new one but decided not to install it. The tape is just too easy to install and remove. Takes only a few minutes to get the top cowl off and do the work. It also gives me one more reason to look at the engine plenum area and inspect what I can see.
 
MacCool said:
I put an Anti-Splat shutter with cable on mine (looks similar or the same as the one Van's sells). I didn't want to mess around with taping/untaping, and wanted the flexibility of in-cockpit control to conveniently accommodate the widely variable ambient temps we often see in this area, particularly in the fall and spring. On a 45 degree day with the shutter fully closed I was able to get over 200°F and on the same flight fully open it ran about 145°.
Click to expand...

I too installed the Antisplat item. Worked very well for ~~250 hrs, then came apart. One of the plates became disengaged from the pin and it fell out of the assembly. Pondering next steps. Sure liked the controllability.
 
Low Pass said:
I too installed the Antisplat item. Worked very well for ~~250 hrs, then came apart. One of the plates became disengaged from the pin and it fell out of the assembly. Pondering next steps. Sure liked the controllability.
Click to expand...

Yes, very convenient item. I don't know about reliability, haven't had it that long. If it breaks, I guess I'll just replace it. Should be easy since all of the mods necessary for the install are already done.
 
Oil cooler baffle.

I cut a piece of .032 aluminum that fits exactly over the cooler fins, then use duct tape on the top 1” of the baffle & tape it to the engine baffle. I have seen cases where duct tape left on the oil cooler fins becomes very difficult to remove. F1A21F9B-6C35-4B19-A927-39C286051A0B.jpeg
 
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