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Oil thermostat - 912S

J

JBPILOT

Well Known Member
In Iowa it can get very cold in the winter. Today it was 12 degrees when I tested the Oil thermostat I installed some time back, waiting for a light wind day to test it. I chose the 205 degree oil thermostat, 98% bypass.

http://thermostasis.com/

RESULTS : Much faster warm-up.
At WOT = 185 degrees.
At 3100 RPM = 201 degrees. ( yes, warmer at slower speed )

John Bender
 
Gosh John, this sounds like a no-brainer for us frozen north guys. (High today was 6F). Did you install before certification or after? Any paperwork necessary? How hard to hook up?

John
 
Good work John. I've been interested in the results with the "new" thermostat. I like the idea of being able to have one set at 205F. Looks like you found one that meets the Rotax getting the oil to spec. once per flight.
 
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Hey Big John

I did it recently ( way after inspection ). In cold weather, it takes for ever to get the oil to 122 degrees. Also, it doesn't warm up much while flying. This solves both. It reduces initial warm up time, thus saves money in gas. If you wanted to get more creative with the hoses, it would make a nicer installation than mine. I may re-do the hose ends now that I know it works well. I am now trying to figure out an air-flow control to control water temps.

John Bender
 
OIL THERMOSTAT

RV-12OilTherm100_1272.jpg

RV-12OilTherm100_1276.jpg


This should give you a good idea of how I installed it. Not a work of art, but functions well.

John Bender
 
Hey big Larry

That's probably the reason it only goes 145 MPH ! Thanks, now I'll be able to fly circles around you.

John Bender
 
Oil Thermostat

John, what was the source from which you got the oil thermostat? Is that a Rotax supplied extra or some aftermarket device? Looks like what would work just fine in the Colorado mountains in winter too.

Thanks for any info.
 
I'm also hoping it will work well for us Texans where ground temps can exceed oil temps. Maybe there's a little airconditioner in the thermostat.
 
Big John

If you go back to my original post, you will see the web-site address for the company that makes this bypass thermostat. I bought the 205 degree model. Under more normal temps., like 20's or higher, it wil keep the oil at proper temps. I think this one is a great unit. Send them a note. They'll send you 912S specific info.

John Bender
 
OIL THERM UPDATE - DAY 2 TESTING

Note : I installed the REIFF preheat system. I have installed an oil thermostat as described above. Today the temp was about 18 or so. I had the preheat system plugged in over night. The oil temp was 94 when I started the engine. I right away started taxing to the strip ( about 800' ). When I got to the strip, it was at 122 degrees. When I taxing to the end of the runway, it was 149 degrees. NO WARM UP TIME. Just start and taxi. These will pay for themselves in a few years. Happy with all the extra work and designing so far.

John Bender
 
Thermostat

I have a Rotax Thermostat that came with the 912 ULS I purchased for my E-AB RV-12. I don't need it in Florida. Thermostat has 20 hrs since new. Open to offers.
Gerry
VAF 172
Repeat Builder
RV-12, N6GC
Cub, NC88583
 
John,

How are you getting the oil temperatures? Is that a function built in to the Dynon, or did you have to add that capability? I really like the idea of being able to control/monitor the temps. Starting to think about this stuff now that my FWF kit is ordered.

John P.
 
Big John

The Dynon displays oil temps. You will be wirng the sender for it when you get your kit. With the thermostat, you can watch the temps go up and down. SO FAR, SO GOOD ! If in a cool or cold climate, I have to believe it is a good idea. Cold oil is not good for the engine.

John Bender
 
Which One?

Hey John,
There are several 205 degree units. Which one did you choose, any why?
I do plan to install one myself. I just need a little help figuring out which one to buy.
Thanks, Tom
 
Oil Therm Info Sheet

OilThermostatfactoryinfosheet.jpg


Hope this info helps. I chose the 205 degree. Also ordered the suggested fittings from elsewhere. Not a simple job, but do-able.

John Bender
 
Awesome info

John - that is very useful info. I have made a copy and will most likely fit my 12 with a recommended thermostat post fly off and testing phase. Thanks again.:cool:
 
It's cold in Ohio, too

John, that looks like an excellent solution. Forgive my propulsion ignorance (I'm an aero)-- I assume that this won't cause any problems on a 95 dreg summer day? A Thermostat usually works by restricting or cutting off circulation until the set temp is reached-- will cutting off the oil circulation cause any problems? I've had radiator thermostats stick with overheating problems-- is there a fail-open mode?
Thanks again for this great idea.

Wayne 120241
 
Hey Wayne

This one really doesn't work that way. The oil flows easily back to the engine thru the thermostat UNTIL it starts to close. When it closes, then it directs the oil thru the cooler. It will warm up faster on a 95 degree day also. Once totally closed, virtually all the oil then goes thru the cooler as before the thermostat installation. No real down-side. Just helps a bunch in cooler weather. Yesterday I flew. It was about 19 degrees. I had the Reiff preheat plugged in over night. I started the engine, and immediately started taxing to the strip. When I got to the turn-around, it was in the 140's. In cool or cold climate it will save gas for sure.

John Bender
 
Heat Exchanger - Laminova

Another alternative I read about was using a heat exchanger to use the cooling water to heat the oil quickly. Can't remember where I saw this unfortunately but I believe it has already been used on Rotax engines. Google Laminova and you will see some sites.

I would insert picture but haven't a clue how to do so.
 
rotax oilcooler and thermostat

RV12

Hi this is the rotax oil thermostat on a Breezer. i'm unsafe about the UNF thread to connect the oil tube.


Daniel #12383
 
Daniel,

Could you provide more information about this option? It looks way simpler than all the connections and hoses required for the thermostasis unit. What specific engine is pictured here? Is this Rotax-approved for use on the 912ULS?

John
 
hufise said:
Hi John

that is the original Rotax Option from the German Rotax Dealer it cost 200 Euro
i don't know about the connections
link in german:
http://www.franz-aircraft.de/Rotax/2011/sonderzubehoer9.htm
the lowest item: switch temp is 87C 188F 251g 8.85oz

the photo is an 912ULS Breezer ULS

Daniel #12383
Click to expand...

Thank you Daniel,

This looks like such a simple installation. Does anyone have any experience with this thermostat? If used on a 912ULS in Europe, why couldn't it be used here? I think this needs to be researched.

John
 
Thermal controlled bypass valve

This German thermostat makes a neat and simple installation. Will it fit in the RV-12? Another consideration is failure mode. Here is a link to a similar device, a vernatherm : http://www.vansairforce.com/community/showthread.php?t=71409&page=3
I assume that most oil thermostats operate on the same principal: expanding media in a cylinder pushes a piston. When the rubber parts of the cylinder fail, the media leaks out and the valve quits working. The 4 port remote mounted thermostats probably have the same failure mode.
The oil thermostat valve is normally open and closes when the temperature reaches the set-point. If the valve fails to close, can the Rotax engine be safely operated at reduced power while maintaining level flight to an airport?
I am asking questions to help me decide if installing a thermostat is advisable or not. There is always duct tape. But duct tape is not automatically adjustable in flight.
Joe Gores
 
Hey Joe - -

Sorry this did not get answered. Just went back to look at it. If the therm fails 'open', it could warm up if in hot weather. In cool, or cold weather, it would not be a problem likely. Just have to watch the temp display. If it sticks CLOSED, it will be just like it was before the therm. Since it runs in oil, with no corrosion, not sure how often these will fail. VERY happy with mine so far. Always warms up much faster than before the therm. Actually helps even on warm days.

John Bender
317.4 hours
 
Installed the thermostats P6-H-190 with the (beautiful made) oil lines made by Tom Swearengen from tsflightlines.com.
Haven't run the engine yet. I will post the difference in warmup time somewhere next week (after completing the 25 hour inspection).

wfwx.jpg


gm0j.jpg
 
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Just make sure the thermostat body cannot touch the plus side of the battery. I think these oil hoses are electrically connected to the airframe and if the thermostat body ever rubs through the silicone boot on the battery .... Or maybe it is just the perspective in the photograph.
 
You have a point Torsten. At the moment the thermostasis has about 1/2" above the terminal. Will fix/protect it in a better way. Thanks.
 
Tom (TSflightlines) and I spoke earlier today, and we will be starting to carry the Thermostasis units for the 912 within a few weeks. In addition, we will offer a complete install kit for this unit including all required fittings.

Once I receive the thermostasis units, I will take a look and see if some mounting brackets need to be machined for the RV-12. If so, those will be designed.

Just wanted to give everyone an update that this package will be available shortly.

Please send Tom or I an email if you are interested in more info.

Have a great day,
Steve and Tom
 
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just in tme

you save me a post!
Barcelona is definitely not Amsterdam, but it gets also cold down here in winter...
Waiting for the solution!

Godo
 
Thermostasis units are on the way. Fittings are being ordered this week.

We should have kit pricing in about a week or so, and will have kits ready to ship in about 3 weeks for anyone who is interested.

If you have any questions, please feel free to contact Tom or I directly and we can give you more information.

Have a great day,
Aircraft Specialty and TSFlightlines
 
Just an update on the thermostasis units.

We have them in stock and very excited about this kit. However, as with all the things Tom and I do, we want to make sure it is perfect before an official release.

Right now we are still waiting on some beta test data to come back to verify the installation and temperature readings.

Also, we are working on a slightly better routing for the oil lines with this customer in order to get a better under cowling fit.

We will keep everyone updated as we complete this project.

Have a great day,
Steve and Tom
 
Thermostasis

I have been experimenting with these units on my 912S powered Kitfox. I originally started with the 180 degree one, but have since had it changed to a 205 degree one. This winter, with temps anywhere from 30 to 60 degrees F I am seeing it go to 205 on climb out and then the valve apparently opens and the oil temp rapidly drops to around 186 and stays there in cruise at 5200-5300 rpms. I have the oil cooler covered over by about 50%. I thought it would hold the temp at 205, but I'm OK with it where it is as it leaves room for climbing and pattern work without getting too hot. I also took the oil cooler completely out of the circuit to see what would happen and the oil rapidly combed to 240 degrees on one trip around the pattern. So using the oil cooler with partial cover and the thermostat seems to be a great solution. I will update this thread when the summer temps arrive.
Just after the next polar vortex. :)

Vic
 
Hey Vic - -

This has been discussed. What the Thermostasis unit is doing and what you are reading are not directly related. The therm reacts to the oil coming from the tank, but is not what goes to the engine. If you are seeing 180F at the engine ( gauge reading ), the tank oil is much warmer. This system is just not like say a therm in your car. The temps you see there will be very close to each other. If we had a tank temp, you would see the therm is working just fine. If you force the oil entering the engine up to over 200F, the oil in the tank is a lot higher, and the oil will break down faster. Hope this makes some sense.
 
Oil Purge?

Is there a procedure for purging the oil system with the thermostat in the oil lines?

If this was discussed back when, I must have missed it.
 
I'm the beta tester. My plane is at home since the 6th of december for the 25 hr inspection but due to conversion training B777 in november and december and now a full schedule I have hardly any time to finish the inspection and install the upgrades.
With the initial setup (see posting 28) the oil line to the pump is rubbing the camloc of the oil door. Discussed different options with Tom. I will receive new/extra parts next week from him. Hopefully I can run the engine before the end of the week otherwise another delay of six days (Hangzhou, China) (Sorry Tom).
The position of the thermostasis is about an inch above the battery terminal, the oil lines are very rigid and there is no need for a bracket. You can tie the oil line to the water overflow bottle.
About purging:
I fill the tank, connect the short line to the thermostasis and the tank, connect the line opposite to the oil tank line and block the other two exits (fingers or the yellow plastic caps delivered with the engine). Pressurize the tank till the oil flows through the cooler. Connect the cooler return line and the oil pump line to the thermostasis and pressurize again. Thereafter connect the oil line to the oil pump.
And then finally a standard purge.
I was advised by several people to go for the P6-H-190 model. Fast warmup time and steady temp during prolonged descent but leaves much more room for final temperature control with tape or shutters.

Greetings from Singapore, Joeri.
 
Joeri...

Tom and I talked earlier tonight about this. Your new stuff is on its way.

What we are trying to do with the routings on future applications is to make it so we don't have to use any low profile fittings. These would add significantly to the cost of the kit if we had to do them on every kit.

We have a routing worked out on paper that will avoid any camloc interference.

If anyone else is wanting to do the thermostasis installation, please send me an email at [email protected]. We have a few overseas customers interested, but what I would like to do is send someone more local all the fittings and the hoses without the ends on them. That way we can play around with the lengths and get everything fitting perfect so we can have a final package that eliminates any sort of potential cowl interference issues.

As far as the model to use, the 190 is the one recommended by the manufacturer for the 912 engine. It is flying on lots of the engines and several RV12s. We haven't updated the website with this kit, but will do so once it is complete.

Once we finalize routings and installation manuals, Tom and I will go over them and make sure everything is all set. Then, we will release the kit.

We have always specialized in doing custom work, and if you are ready to get your thermostasis unit on your plane, we can work with you right now to set it up. But, we also recognize that lots of builders/owners are looking for a turn key solution with all the lengths already figured out and offered in a complete package. So, that is why we are making sure everything fits perfect and easily before we release the official kit.

Have a great evening,
Steve
 
Hey Tony - -

What I do. I take the cooler off each oil change and drain it and the hoses. I also turn the engine over for a few seconds to get the oil from the inlet thru also ( with plugs out ). I then re-install the plugs and burp it. I fill the tank to the very top until it is in the neck. With plugs back out, I use the starter to turn it over for 5 seconds. I then look at the tank to be sure the oil level is going down. If yes, then I use the starter to turn it over until the pressure comes up to about 65 lbs. Takes about 20 - 30 seconds usually. I then put heat paste on new plugs, install, and burp it again so I know where the actual oil level is, then add accordingly. I get a complete oil change, and never a problem. This is not the Rotax method, but I like it, and know I have no air leaks because it is sucking oil from the tank. All hoses including the therm are suction hoses. Only hose with mild pressure is the return to tank hose.
 
Oil temp

John, I hear what you are saying and a I have seen the discussions. However, Rotax is telling us to measure the oil at the inlet to the engine, and the recommended temp ranges are spec'd using those readings, not the tank readings. If they were taking into account the higher tank reading then they would have us look or a lower inlet temp.
It is the same with Lycomings. We are measuring the inlet and definitely the oil in the sump and going to the cooler is much hotter.
I was trying to share my experience in using the 180 and the 205 degree thermostats unit. I'm satisfied with the readings now with the 205 degree unit. The 180 degree unit allowed the temps to remain too cool at 165. I would bet your experience with the 190 degree one would be the same. :)

Vic
 
Hey Vic - -

I am using the 205. In very cold weather, say 20F, my display may be as low as 160. I know the oil in the tank is 205 or so. The oil temps that get up to 250 or more in the tank to me are too high. If you are forcing the inlet temps to 200 +, the oil temp in the tank may be high. Actual air temp changes everything. With a 205 therm, you know the temp at the tank is 205 or more, and then the therm directs it thru the cooler, or blends as needed somewhere between 195 and 205F. I really don't care how low the oil at the inlet is, as long as it is over 122F min. The info I have seen seems to indicate running oil at 250F or more breaks it down faster. Do what you feel comfortable with. In the summer, I know when we see 230F at climb, the oil in the tank is much higher. Can't get around that, except to level off and decrease the temps. To me, the therm solves the problem of getting the oil warm enough to keep moisture out. I never see any signs of moisture in my tank. I also plug mine in 24/7 during cold weather, and that likely helps that also.
 
All--. This doesnt seem like a complicated install. Actually, Joeri and I have been working on this for a while (October). Not having a RV12 here to sit down and plan routings is TOUGH. He is in the Netherlands, and trust me shipping stuff to the Netherlands is not cheap. (WE worked out some 'creative' shipping methods for the initial package, and some subsequent packages.)
Anyway, Steve and I want to make this install as turnkey as possible, like we did with the Rotax fuel hose upgrade. Overall, the install looks good. I've sent out a modified hose to try to improve the routing slightly. All of this takes time, and unfortunately money. But, I have the confidence that we will have this perfected soon.

Note---As many of you know Steve at Aircraft Specialty and I have partnered on several projects, this being one and more on the board. WE still are separate companies, with our own unique services. Steve makes many great parts for experimentals. WE chose to partner up on some projects to better serve you, our customers, not only with great products, but with assets that we can share. I'm not good at promoting, and he certainly is! So---for alot of the packages that we are developing, he has taken the lead in advertising, installation manuals, pictures, etc, and I have been in the background doing the R&D. That R&D not only is for packages, but for hose and fluildine development to allow you guys to be safer, and enjoy your RV's.
TS Flightines is still here---I'm not going anywhere!
Tom
 
Tom is absolutely correct about putting these packages together. This isn't nearly as in depth of an R&D project as the 912 fuel hoses were. However, we are committed to making these packages perfect in their final form so that they will fit in each aircraft in the best possible location and with ease of access for maintenance of components in the future. It is part of our personalities to always keep improving.

We have secured another aircraft here in the states to run some hose routing testing on. This will be started in the beginning of February and we are aiming for a final hose routing decision sometime that month. We are getting very close.

To touch on what Tom said. It has been an absolute pleasure working with him over the past few years. He and I have the same customer service commitments and as such are completely aligned in our goals and commitment to provide absolutely top notch service and products. A lot of companies come and go, but we are both here to stay. Both of us can't say enough how much we appreciate the opportunity you have all given us to work with you on your projects and feel like part of your build. Though we are still separate companies, we talk on a daily basis and have a lot of new ideas up our sleeve and in the pipeline.

One of us will post again as we get closer to completion. But, if you have any questions in the meantime, please feel free to email one of us.

Steve
 
Received the parts from Tom last week. In the picture you can see the install like the way it is now. The thermostasis is secured to the overflow bottle.
Run the engine on friday. Outside temperature was 41F. Warmup (up to 122F) 4m50s.
Warmup in september (59F) without the thermostasis 8m45s.
I had some fuel pressure problems on my last flights. Checked everything and could not find the problem. Installed the new fuel lines from Steve and the pressure is now a steady 5psi.
Hopefully back at the airport next week for flight testing.

s5p9.jpg


n06g.jpg
 
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Joeri,
I definately like this routing better than the last. Guys, this is protype install of this unit, and Joeri is doing the install and the beta testing, in the NETHERLANDS! Of course, this works for HIS plane, and may not be the final configuration. But, his temps are consistant, and with our fuel hose package, his fuel pressures are consistant.
Steve and I have beta testing progressing with other configurations, but not flying as yet. Eventually, we will have settled on a final location for the thermostasis, and hose lengths and configurations.
Overall, we are pleased with the outcome of this package. More RV12 stuff in the pipeline, as well as other R&D projects ---all going on at once. All to better serve our fiends in the experimental community!
Tom
 
Joeri...

Glad to hear that your fuel pressures are working much better. The kit that Tom and I worked on is a very robust and high quality alternative to rubber lines. We hoped to eliminate so many of fuel system inconsistencies that others had experienced. We designed a package that can be installed in every airplane and achieve the same results.

As Tom alluded to, the thermostasis install is coming along well. We are going to be stocking thermostasis units and complete install kits. Right now, we have another builder beta testing an install based on Joeri's hose lengths. We are going to tweak and get everything perfect and then release this kit to market also.

And, we have a few other items up our sleeves also. This has been a lot of fun for Tom and I and we are continuing the joint ventures with a bunch of other projects.

Steve
 
First time flying for 3 weeks - -

Been really cold and windy in Iowa this winter. Finally got to fly today. Was MINUS 10C at 5000'. At -MY- normal cruise, 108 knots, oil was 165 - 170 degrees. Just fine for me. I forced the CHT's up to 195 - 200 degrees ( heater damper door ). Made it very comfortable. Latest gas tank mod and tank vent seemed to work well.
 
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