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Winter Oil temps

yankee-flyer

Well Known Member
Since doing the "move the cooler" mod I've been experimenting with blocking off part of the oil cooler with duct tape, with a view to a detachable aluminum plate. Temps are at the end of a 75 kt. climb to 4500 ft, and then steady-state cruise.

50 deg f no tape: 220, 210-215

40 deg, 2" tape: 235, 223-227

40F, 1"tape: 225, 215

30 F, 2" tape: 220, 215

Looks like I'll continue using tape instead of an aluminum plate. Last winter, even with the cooler snugged up against the muffler, I rarely got to 220 deg.

Wayne 120241/142 wM-- waiting for a 90F day to check out the cooler move!
 
Big day today, as we did our first engine run!

Oil cooler needed the tape job - especially with the cowling off. OAT = 40 F.

What I'd like to see is some bright guy on this forum design an oil cooler cowl flap adjustable from the cockpit, like some other Rotax powered LSA airplanes have (Aerotrek, for one.) Then you could warm up faster, as well as dial-ur-size for the conditions you have at the moment.

Bob Bogash
N737G
 
What I'd like to see is some bright guy on this forum design an oil cooler cowl flap adjustable from the cockpit, like some other Rotax powered LSA airplanes have (Aerotrek, for one.) Then you could warm up faster, as well as dial-ur-size for the conditions you have at the moment.

Bob Bogash
N737G

Hey Dave Valcek, Should we break our silence?
 
Bob,
Someone has already done it but I cannot recall who it was. They posted pictures on the forum.
 
Ok, Dave - still under development

Well Dave and I have been working on a shutter. I am having a few cnc?d larger versions of the shutter that will fit the Rotax oil cooler.

shutter.jpg


The thought is to use two cowl guide facing forward( on the bottom) and the current AN3 bolts to attach the shutter

shutter cone.jpg

.

Will post once we are finished.
 
The shutter you are looking at in Dave Valcek's post is a stock part obtained from Van's. It is not large enough for the stock Rotax cooler. I am currently using another "prototype" that has cut my warm-up time almost in half. It is controllable by a cable just like the heater cable. I am using it for ground operations only and it is very effective. It is a flap that is hinged at the bottom and covers the entire oil cooler. I can be opened in flight at low speeds. It does not address the issue of en-route temps. We are hot on this and will keep all posted.
 
Hmmm... I would prefer one that could only partially block the cooler even in any possible failure mode. I would take the additional ground warmup time rather than the possibility of total blockage. The slotted panel appears to cover a lot of the surface area even when fully open, not good for the summer in a -12. Vans personal RV-12 has a shutter with panel knob but I don't think I took pics of it the time I saw it - I'll recheck.
 
Hmmm... I would prefer one that could only partially block the cooler even in any possible failure mode. I would take the additional ground warmup time rather than the possibility of total blockage. The slotted panel appears to cover a lot of the surface area even when fully open, not good for the summer in a -12. Vans personal RV-12 has a shutter with panel knob but I don't think I took pics of it the time I saw it - I'll recheck.

I tried a flap that partially blocked the cooler and there was no significant change in the warm up time. If the flap closes in flight, I can slow down to 60 knots or so and pull the nose up and it can be opened right up. Our idea is to make it quickly removable in the same manner that the oil cooler is removed, for summer use.
I am currently using this version and am very satisfied so far, but the next version will be better.
Regarding the additional warm-up time, I have sat on the ramp waiting 5 minutes to go from 119 to 122 and it gets old. We are not saying this is for everyone. Many climates won't require it.
 
Oil Cooler Cover

I made an aluminum cover to block off part of the oil cooler in below freezing temperatures.
Joe Gores
Oil%2520Cooler%2520Cover.jpg
 
I have the oil thermostat 209F and a metal flap like Joe made for temps under 35F. Oil temps are nice and toasty. :D
 
Oil cooler shutter

Finished installing the Oil Cooler Shutter.

I used the an3 bolts on the top and added 2 cowling guides on the bottom. I needed to grind one side so they would fit with the slope of the bottom cowl.

shutter 1.jpg

shutter 2.jpg


Created a frame for the shutter sold by Vans

shutter 3.jpg

.
shutter 4.jpg

shutter 5.jpg


I forgot to take pictures of the cable placement inside the cabin. I mounted the two cables on the pilots left side under the panel next to the air intake, one for the radiator baffle and the other for the oil cooler shutter.

Bring on the cold :D
 
Oh yeah, very nice job! Much more elegant than my fixed plates covering half of the two coolers. They help a lot, but it would be nice to have something adjustable. Also would be nice to have a coolant temp gauge so radiator could be adjusted using more than CHT as a guide. Maybe a project for next year.........
 
Thermostat problem

I am probably the only forum member to have a problem with the thermostasis unit. Installed, one, oil warmed up very quickly, and as soon as the unit opened (210 deg) my oil pressure dropped to about 15 pounds. Shut down checked everything, no leaks. Repeated process several times, same result. Checked the oil line routing and posted pictures so those who had already installed one could check, looked OK to everyone. Removed thermostat, everything normal. Reinstalled thermostat (more oil, more purging the system) and had the identical problem. Contacted manufacturer who insisted that the problem COULD NOT BE with their device. Sent photos, they OK'd the oil line installation. After much discussion they refused to exchange my unit for another one but finally did agree to refund my purchase price -- (go fiugure that one out!) but not the money to send it back. That left me holding the bag for a bunch of oil line and firesleeve and waiting for the oil to warm up.

That said, others have had great success with theirs and I might have a happy story if they'd been willing to simply exchane the unit for another one.

Wayne 120241/143WM
 
Hey Wayne - -

no idea why you had a problem. Could you post a picture again of the installation. I never bleed mine. Just turn over with a set of plugs out, and it bleeds itself. I also take the cooler off each time to get a complete oil change.

Trying to help. I remember you talking about this. Wish you were closer, I'd like to see what is happening. Might be because you are trying to "pre-bleed" the hoses. Let the pump pull the oil thru the system. It takes all the air out that way.

John Bender
 
Great Job David and Dave!:eek:

John, this Dave Valcek's creation. Can't take credit for this. The one I am currently testing is different in that it is a flap that is hinged at the bottom and either fully covers or uncovers the oil cooler and as i stated previously, it does not address the enroute oil temps. If the weather ever clears here, Dave will test his creation and let us know. We are considering fabricating a larger damper for the Rotax of the same design. Truthfully, we are thinking that there might be too much area covered by the Van's part making it useful only in the coldest of climates, but we will know soon. Keep ya'll posted. Dave has some pics of the one I am using, maybe he can post them?
 
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Nice looking shutter system. It will provide good manual control but as others have noted, always blocks some flow and can have a bad failure mode. For those moving from a "traditional" RV with a similar system or a complex airplane with cowl flaps, this is a good choice.

Tape is cheap and effective, but is not controllable from cockpit, looks like **** and doesn't help warm up time that much. Did I mention that its cheap? Down side is that dumb pilots sometimes forget to take the tape off when a warm spell hits, then are surprised when the oil temp hits 240 on climb out. Not that this ever happened to me....

Oil thermostat is great for minimizing warm up time, requires no manual control (no forgetting to take the tape off when it warms up), but is expensive and harder to install. Highly recommended by many Rotax shops and very common on some S-LSAs.

There is no perfect solution. For those living in areas where it rarely freezes, tape probably works best. Outside that, thermostat or shutter, depending on whether you want to do it yourself or have the thermostat do it for you.

TODR
 
John, this Dave Valcek's creation. Can't take credit for this. The one I am currently testing is different in that it is a flap that is hinged at the bottom and either fully covers or uncovers the oil cooler and as i stated previously, it does not address the enroute oil temps. If the weather ever clears here, Dave will test his creation and let us know. We are considering fabricating a larger damper for the Rotax of the same design. Truthfully, we are thinking that there might be too much area covered by the Van's part making it useful only in the coldest of climates, but we will know soon. Keep ya'll posted. Dave has some pics of the one I am using, maybe he can post them?

You have to consider the area taken by the fin structure versus free air. I think it works out (as I remember). Several of us around here has used the Van's sliding system on our Lyc 320/360s where summer temps reach the mid 90's & winters in the 20's. It's worked well.
 
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