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Warming up the oil faster?

Bill_H

Bill_H

Well Known Member
OK, cold weather is upon us. I have a blower and duct to prewarm the engine as the plane sits in the hangar. Can easily get it up to 70 degrees or so. BUT - then you have several minutes of idle getting to 120 degrees - during which you are fighting the fact that cold ambient air is going through the oil cooler. The situation is even worse if you have no preheat and are starting at -say- 35 or so degrees.

SO - I dont really want to put on a winter aluminum cover plate covering part of the front of the oil cooler. (Maybe I do, dont have much cold weather in-flight experience yet in the -12. Maybe it will run too cold? But I'd be concerned over getting the partial block plate sized correctly. But that's another question...)

THE QUESTION: What about an installed-from-the-front plug or easily attached-removed cover plate that totally covers/blocks the oil cooler (BUT NOT the part of the duct that goes back to the coolant radiator!), that you put on right before startup. You warm up to 120 much more rapidly, I would think. Then you shut down, hop out, take off the plug, hop back in and restart - because the Rotax start so easily. Anything wrong with this scenario?

I dont want to install one of those cockpit-controllable variable-blockage oil cooler cover plates - because they block some flow in the summer and we KNOW we have summer issues with the -12 oil temp! Also worry about failure modes... (I don't currently have the heart to take a cutter to the cowling and somehow move the cooler forward another half inch. The posted mod on that looks scary for a completed plane...) The winter-only startup-only plug idea has some attraction.

Issues?
 
This has been covered several time - -

A Thermostasis Oil Therm warms the oil up the fastest. Virtually no oil goes thru the cooler until it gets up to temp. I also use a Reiff Pre-heater. I can start, immediate taxi, and ready before I get to the runway. Saves lots of time and gas. Can't beat that combo.
 
Bill,
I have done exactly what you are contemplating. I stuffed an old blanket into the large opening of the cowl to block off air to both the oil cooler and water radiator. After the engine warms up, I shut down and remove the blanket. Now the only problem with that is for people like me who suffer from CRS syndrome is, do not forget to pull the plug before takeoff. :D
I also made an aluminum cover to block off part of the oil cooler. The exact size of the cover will depend on your climate. Start off with the size that I used. You can always cut part of the bottom off later if required. I flew last winter with that oil cooler cover with no problems. Duct tape works too.
I also made a small cover to block off the part of the water cooler that extends above the firewall shelf. But I have not flown with it yet.
Joe Gores
Oil%2520Cooler%2520Cover.jpg
 
Tale of two days - Flew Weds - OAT 34 degrees; Thurs - OAT 32 degrees. It took forever to warm up the first day so - Before flying Thurs, I taped over the top third of the oil cooler with duct tape (never leave home without it.)

Measurements from Savvy:

Time to 122 deg F

Weds - 17 min Max temp 177

Thurs - 9 min Max temp 217

All other params pretty much equal.

Bob Bogash
N737G
First Flight - 3 April 2013
On shutdown yesterday - 100 hours !!!
 
I have been using a cockpit controllable shutter that blocks airflow completely for several years now and like it. I remove it when it gets warmer in the spring. Mine is one that I fabricated. When it gets colder, I block off approx. 1/3 of the oil cooler also. The oil thermostat is probably the best way to go, but I have something that works well, so it's staying for now.
 
Bill_H said:
THE QUESTION: What about an installed-from-the-front plug or easily attached-removed cover plate that totally covers/blocks the oil cooler (BUT NOT the part of the duct that goes back to the coolant radiator!), that you put on right before startup. You warm up to 120 much more rapidly, I would think. Then you shut down, hop out, take off the plug, hop back in and restart - because the Rotax start so easily. Anything wrong with this scenario?
Click to expand...

Because one day, no matter how many self reminders or checklist items you have, you will forget to remove the plug. It's just that simple.
 
Duct tape leaves sticky residue. Try aluminum ducting foil tape. In spring you either cut a bit away each month or just pull it off. Used in Alaska on all the oil coolers.
 
I have the aluminum tape. I think i can avoid forgetting the towel/blanket by hanging a bunch of streamers in front of the skyview and wrapping a bungee cord around the throttle where it can't be advanced to full. Something like that, you could make an aluminum clip to fit over the throttle shaft to prevent any advancement over idle. There are throttle locks like that.
 
Another comment - -

With the Thermostasis Oil Therm, even in warmer weather, you save gas by not having to wait as long to get to 122 F. I'm guessing the therm will pay for itself over the life of the plane engine, and lots of time saved also for flying, instead of sitting warming up. In colder climates the Reiff Pre-heat is absolutely perfect. I put a packing blanket over the nose and clip it together in the front. If it is 25 F outside, you can open the canopy, and turn on the Dynon, and the ENTIRE engine is 90 - 94 degrees. All 5 temps read very close to each other. I know it takes money and time, but both work great. No messing or guessing how much to close off the oil cooler, or rad.
 
Just my own opinion and yours may differ.

The majority of the guys I know just use the aluminum tape because some other tapes leave a glue gooey mess behind. It keeps temps over 200F for about $.10 cents. Takes seconds to apply or remove. I usually put a 2" wide strip all the way across the top of my radiator (my oil cooler is piggy backed on the back side). I apply it in Dec. and pull it off in Feb. My oil temps are always above 200F.

Just my personal view and certainly yours may differ.
The thermostats are nice, but I think the engine pre-heaters are better for cold morning starts. The thermostats do help keep temps above 180F-190F while flying, but many times tape may be needed to give it the extra boost in temps over 200F while flying.
The two that most used are Tanis and Reiff. The gold standard for engine pre-heaters has been Tanis.

So the perfect solution may be a combo of all three if you live in cold country.

Just food for thought. What ever works for you is good.
 
Roger - -

The Reiff pre-heat cost $229. Tanis is 3 times more. I see nothing of an advantage with the Tanis. If you cover the nose with a packing blanket, the ENTIRE engine gets universally warm. No hot spots, or cold spots. The oil therm works year around. It speeds warming in any weather. Never have to adjust anything. Start and go.
 
My duct tape was a quick and dirty experiment. I have many rolls of that "aluminum tape" - from my airline days - we used to call it "600 mph tape", or "High speed tape" and used it liberally.

But it leaves a residue also, and isn't very flexible for contouring to the cowl/cooler inlet. The residue is no big thing and comes off readily with a little paint thinner or fiberglass boat cleaner.

Also, easy to add or remove depending upon how warm or cold the day is.

Bob Bogash
N737G
 
Hi Bob,

Don't use the heavy aluminum tape. Try the thinner paper backed aluminum tape. No residue and does the same job. I over wrap the top 1/4" edge of the cooler and about 1.5" around the ends. The front doesn't stick at all on the fins so there is no residue. It only blocks the air flow. I have been using it for 12 years and I know many in the LSA world use it too.
You can get it at Ace Aviation (Ace Hardware)

Rotax video on cold weather affects on engines and the Tanis pre-heater

http://www.rotax-owner.com/all-videos/product-reviews/149-tanis
 
Last edited:
Blast Gate

Oil cooler mounted on firewall. Blast gate on scat tube adjustable from cockpit with cable. Can control from completely closed to wide open. Monitor oil temp on EIS, adjust as necessary. Aluminum Blast gate available from woodworking supply stores.
 
Keeping life simple and light, we have an oil cooler blank made from 0.032" ali sheet held in place by the top oil cooler attach bolts.

4mza.jpg


Coolant rad is also 0.032" ali and slips in between the cowling seal and the coolant radiator. Top and side edges have a slight return to prevent it from slipping. Fitting only requires the top cowl off and the left hand upper (short) cowl pin pulling.

rej7.jpg


Oil temp and CHTs now stay within few degrees of each other and always in high 80s with air temps down below 0 degC.

Oil temp is up to power check level (50 degC) within 5 minutes - pretty much by the time after start checks have been completed, route planning is in the SkyView and one has taxied up to the Hold for power checks.
 
oil cooler preheat

maybe an oil cooler is like a ''bear scare'' in a back yard of chicago but i put a $25 stick on silicone pad from an auto store on my oil cooler so less chance of rupturing the cooler with thick oil. pad goes on with my other preheat pads.
 
bobnoffs said:
maybe an oil cooler is like a ''bear scare'' in a back yard of chicago but i put a $25 stick on silicone pad from an auto store on my oil cooler so less chance of rupturing the cooler with thick oil. pad goes on with my other preheat pads.
Click to expand...

Bob,

Could you please explain? What type of silicone pad do you mean?

John
 
Red Duct tape

40-50 DEg-- cover 1" of cooler

30-40 deg 1/3 of cooler

20-30 deg 1 full strip of tape on coler

Below 20 deg-- stay home and watch an aviation movie.

Wayne 120241/143WM
 
john,
carquest, etc. can order a silocone heater pad for you for about $20. i think they are made by ''jegs''. come in the 100-200 watt size for oil pans and they also make a 25 watt that is about 1.5'' x 4-5''. perfect for a positech type oil cooler. i put one on mine and it gets turned on when i preheat. whether or not it is really needed i don't know but the oil cooler gets warm at preheat time.
 
I was experiencing the same long run time to reach 122 during these cold mornings so I tried the thin aluminum tape with the peel off backing. One strip across the bottom of the cooler.

It warmed up quicker and in flight the temps stayed around 215 to 230. I feel it was a success. Today was one of those Colorado mornings which started in the high 30's and was in the 50's by afternoon. But during my flight it rose into the 40's but I was fine with the oil temps.

I will continue to use this method and monitor results in different temp ranges.
 
After flying quite a bit in recent cool weather, and fooling around with blocking various percentages of the oil cooler, I'm convinced the airplane really needs a cockpit adjustable oil cooler control.

On a recent flight - posted above - the oil temp took forever to warm up, and then was too cool in flight. After a temporary tape job, the warm-up time was cut in half and the in-flight temp was where it should be.

But then, on an even later flight, the oil temp became unacceptable (to me.) The temp was about 30 deg F on the ground, and the engine oil warmed up quickly, but then in cruise it rose way too high into the yellow band to suit me, so I landed and removed the tape. The rest of the day was OK.

The problem in this case was a significant temperature inversion - something we get frequently here in the PNW and something that can last for days, or weeks. So - I took off with the OAT at 30 deg F. By the time I reached 2500 - 3000 ft, the OAT was 65 deg F. Now the oil cooler needed more cooling air.

Whatever blocking scheme is used would be problematic in this situation. The ONLY solution to controlling the oil temp satisfactorily, it seems to me, is a cockpit adjustable shutter control of some sort - various have been described on this Forum. Or, perhaps, the oil thermostat.

I flew with a friend on a cold day in his AeroTrek - it has a Rotax 912ULS engine installation, very similar to the RV-12. But, it has an oil cooler control (something added later in the production run). It's an S-LSA. He used it to precisely control his oil temp and it worked well. Photos here:

http://www.aerotrek.aero/photos/oil-cooler-flap/oil-cooler-flap-m.jpg

http://www.aerotrek.aero/photos/oil-cooler-flap/flap-large-980.jpg

Bob Bogash
N737G
 
Bob or others, what about your CHTs? Where they too low? Ive seen the adjustable duct baffle to the coolant radiator purposed mostly for cockpit heat control, (with the exception of the insertable baffle shown earlier in this thread) but in flying on a 30 degree day I also saw CHTs down just below 165. I just reached in and checked and I could apply aluminum tape to the radiator via the fishmouth. Easy to remove that way if you fold a little tab at one end.
 
Oil Cooler Shutter

I have my oil cooler mounted on the firewall low and behind #3 cyclinder. I've installed a cockpit controlable oil cooler air source on the baffling behind #3 cyclinder. The pictures should speak for themselves....

http://i1197.photobucket.com/albums/aa433/wstucklen1/Oil Cooler/OilCoolerAirValve3.jpg

http://i1197.photobucket.com/albums/aa433/wstucklen1/Oil Cooler/OilCoolerAirValve.jpg

http://i1197.photobucket.com/albums/aa433/wstucklen1/Oil Cooler/OilCoolerAirValve2.jpg

http://i1197.photobucket.com/albums/aa433/wstucklen1/Oil Cooler/OilCoolerAirValveopening.jpg

<a href="http://s1197.photobucket.com/user/wstucklen1/media/Oil%20Cooler/OilCoolerAirValve2.jpg.html" target="_blank"><img src="http://i1197.photobucket.com/albums/aa433/wstucklen1/Oil%20Cooler/OilCoolerAirValve2.jpg" border="0" alt=" photo OilCoolerAirValve2.jpg"/></a>


Bill_H said:
OK, cold weather is upon us. I have a blower and duct to prewarm the engine as the plane sits in the hangar. Can easily get it up to 70 degrees or so. BUT - then you have several minutes of idle getting to 120 degrees - during which you are fighting the fact that cold ambient air is going through the oil cooler. The situation is even worse if you have no preheat and are starting at -say- 35 or so degrees.

SO - I dont really want to put on a winter aluminum cover plate covering part of the front of the oil cooler. (Maybe I do, dont have much cold weather in-flight experience yet in the -12. Maybe it will run too cold? But I'd be concerned over getting the partial block plate sized correctly. But that's another question...)

THE QUESTION: What about an installed-from-the-front plug or easily attached-removed cover plate that totally covers/blocks the oil cooler (BUT NOT the part of the duct that goes back to the coolant radiator!), that you put on right before startup. You warm up to 120 much more rapidly, I would think. Then you shut down, hop out, take off the plug, hop back in and restart - because the Rotax start so easily. Anything wrong with this scenario?

I dont want to install one of those cockpit-controllable variable-blockage oil cooler cover plates - because they block some flow in the summer and we KNOW we have summer issues with the -12 oil temp! Also worry about failure modes... (I don't currently have the heart to take a cutter to the cowling and somehow move the cooler forward another half inch. The posted mod on that looks scary for a completed plane...) The winter-only startup-only plug idea has some attraction.

Issues?
Click to expand...
 
Fred - this is RV12 specific.
Nice use of the blast gate though! It looks like you are push-to-close. So if the wire breaks inside the sheath you can only close, not open. Seems to me that push to open might handle that failure mode a bit better - assuming (I don't know) that a broken wire still in the sheath can push the broken wire piece (not "pass" it and jam up?)

Bill
 
Cold Day Flights

No oil cooler cover:

OAT on takeoff = 33 deg F
Flt duration = 48 minutes
Max oil temp = 176 deg F
Avg Oil Temp = 163 deg F
Altitude = 2300 ft
OAT at 2300 ft = 28 deg F
Avg CHT = 72 deg C = 162 deg F

Oil cooler cover tape - approx top 1/3

OAT on take-off = 39 deg F
Flt duration = 1:00 hour
Max oil temp = 217 deg F
Avg oil temp = 206 deg F
Atitude = 3500 ft
OAT at 3500 ft = 32 deg F
Avg CHT = 74 deg C = 165 deg F

----------------------------------------------
Temp Inversion Day Flights

OAT = 62 deg F - 3000 ft
Oil Temp w/cover = 239 deg F
Avg CHT = 89 deg C = 192 deg F


Oil Temp w/o cover = 203 deg F
Avg CHT = 89 deg C = 192 deg F

The above demonstrates the power of a thermostatically controlled liquid cooling system - keeping the CHT's very uniform throughout the flight.

The above retrieved using the Dynon data downloads and the Savvy Analysis system.

Bob Bogash
N737G
 
Thanks, Scott - I thought there must be one in there - well, it proves the value of a liquid cooling system!

Bob
 
Oil Shutter

Yes, it's push to close via the cockpit cable. But the shutter is located near the oil door on my RV-7A, so could be opened or closed on the ground (and locked with a thumb screw) if necessary. I've never seen a wire break inside the sheath under normal circumstances. The wire tends to break outside the sheath, in which case the shutter will open via gravity.....

Bill_H said:
Fred - this is RV12 specific.
Nice use of the blast gate though! It looks like you are push-to-close. So if the wire breaks inside the sheath you can only close, not open. Seems to me that push to open might handle that failure mode a bit better - assuming (I don't know) that a broken wire still in the sheath can push the broken wire piece (not "pass" it and jam up?)

Bill
Click to expand...
 
Oil hose routing for Thermostasis

Did you change the routing of the oil hoses around the engine and where did you locate the Thermostasis unit?
 
My original installation - -





No real mount for the Thermostasis therm. The short hose holds it very securely. Works great. Hose routing is VERY important so as to not get the hose near the exhaust.
 
cold weather flying

Snow from a few days ago, clear and cold today (5 to 10 deg @ 2000 ft), but left the office early today and got an hour of flying in. More snow and wind this weekend so glad I got some quality flying in.

cold%202013-12-13b.jpg


cold%202013-12-13a.jpg





DIY heater.jpg

DIY heater

shutter 4.jpg


shutter 5.jpg

Cabin adjustable shutter for the oil cooler

The heater worked great, my guess the inside temperature of the cowl is about 75 deg - 80 deg. I pulled the plane out and started up, within 1 min temps were 100 and at 3 min after my EFIS had calibrated, I had temps of 124 deg. I have a shutter system in front of the oil cooler and I had it completely closed. By the time I was a the run up area I had temps of 160 and open the shutter about a 1/4. In flight temps range from 190 - 230 depending on the amount of opening in the shutter.

Bottom line no waiting for wheels up :D
 
Last edited:
On Lycoming engines there is no minimum oil temperature.

Operators Manual said:
Engine is warm enough for take-off when the throttle can be opened without the engine faltering.
Click to expand...
 
After you became airborne, how effective was the heater for the interior of the cockpit?

Did it seem adequate or could you have used a little more hot/warm air?
 
Driftdown said:
After you became airborne, how effective was the heater for the interior of the cockpit?

Did it seem adequate or could you have used a little more hot/warm air?
Click to expand...

If you perform the Bender mod in the cowl duct, you can have it toasty in the cockpit. If not, you will be cold.
 
Thanks Dave - -

I force the CHT's up to about 200 - 210 F. That slows the air going thru the rad., and you get great heat from the rad. When it is cold, this becomes the best mod of all. REIFF pre-heat keeps it warm over night, the oil therm keeps the oil at proper temps, and the 'damper door' makes it warm inside. Makes this plane an all season plane.
 
Dvalcik said:
Snow from a few days ago, clear and cold today (5 to 10 deg @ 2000 ft), but left the office early today and got an hour of flying in. More snow and wind this weekend so glad I got some quality flying in.




DIY heater.jpg

DIY heater
Click to expand...

Hey Governor, your heater looks like something I saw on a recent episode of Moonshiners! Is that some kind of air still? You could get arrested in Virginia for having that! Gonkulator? (FKKA);)
 
Wonder?

Wonder if Van's will incorporate any of these 'Bender Mods' into the kit? Seems like a good idea to me. I'd rather get my kit already 'modified' rather than have to perform surgery after certification. These could be great changes of an already outstanding kit aircraft. Thank you Mr. Bender and others who lead the way!
 
Very cold weather

I made a cover plate that covers the entire oil cooler I then cut 2 holes in the plate 2 1/4 inches in diameter. Mounts with the top oil cooler mounting screws.
I have tested the aircraft with OAT at -5 F. Works well keeps inflight temps in the middle of the range. Previously with out the plate temp would drop below 120 when power was reduced for landing. This seems to be a necessary mod here in Minnesota.
 
Something to keep in mind - -

the oil temp you are reading is at the pump ON THE ENGINE. If you are seeing 230 degrees there, the oil in the tank is MUCH warmer. Oil temps going into the engine are better to be at 200F or less. Would be better if we had a temp prob in the tank also. In the winter, I see oil temps of 180 degrees, and that is plenty. The tank is much warmer, and the oil coming from the oil therm to the engine is a blend of oil from the tank and cooler.
 
John,

Since the ROTAX limits are based on installed sensors and their design locations it would seem the oil temp difference between pump and tank is accounted for.

Rich
 
Manifold pressure sensor

Where do you think the manifold pressure sensor for a GRT 0-360 engine might be?
Thanks
 
Rich - -

If you have or don't have an oil therm, if the oil has gone thru the cooler, and it is still 230 F at the pump, it has been much warmer in the tank. If you are seeing 230 F, you are at the limit for sure. Seeing that in cold weather would seem to me to indicate it has been very warm in the tank, and maybe covering up too much of the cooler could be a problem is what I was trying to say. Didn't qualify my statement well enough.
 
John, I get what you're saying. My reasoning is that as long as you have design flow rate on the oil side you should be within ROTAX limits everywhere if you keep the monitored location within specified limits. Am I missing something?

Rich
 
Rich - -

basically agree. I feel running near the edge is not good for the oil. Again, we really don't know what is normal temp IN THE TANK. I am using the Thermostasis 205 degree model. In very cold weather, sometimes I only see 165 on the display. I know the oil in the tank is 205 or maybe even slightly higher. If you are reading 230 on the display, and no therm, the tank oil is much warmer. If the oil in the tank is 250 degrees,I feel it will break down faster than at slightly lower temps. In the summer, during climb, I have gotten to 230 degrees, and I back off. Would have to see what an oil expert would say about best temps for the oil to be at.
 
E. D. Eliot said:
Wonder if Van's will incorporate any of these 'Bender Mods' into the kit? Seems like a good idea to me. I'd rather get my kit already 'modified' rather than have to perform surgery after certification. These could be great changes of an already outstanding kit aircraft. Thank you Mr. Bender and others who lead the way!
Click to expand...

Scott, any comment on this? Would be a good selling option for us up-north types. Especially for us non-engineer guys who are not too good at fabricating our own designs. BTW, any news on the weather stripping kit?
 
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