What's new
Van's Air Force

Don't miss anything! Register now for full access to the definitive RV support community.

TWC butterfly valve for oil cooler - experience

Michael Wellenzohn

Michael Wellenzohn

Well Known Member
Sponsor
Hi,
I learned today that the OAT is so low that my oil temp won't make it into the green. So I will have to install a butterfly oil cooler valve.

What are your experience with the TWC control valve servo kit?

Does anyone have a chart which puts cooling performance in relation to position of the butterfly valve or reduced throuput-area?

Regards
Mike
 
I just built my own.

It look and works just like a carburetor throttle blade. This assumes you have the oil cooler remote mounted and not hanging on the back of the baffles.
 
I don't have the TWC valve, but another make that I think I got from Craig Vince. It works very well with a simple push-pull cable. We can have dramatic temp changes in Colorado day to day, or even in the course of a single flight. It is easy to tweak(not twerk) the valve to exactly the oil temp you desire. I don't have a chart, and don't think it would be useful, as a specific valve position will result in different oil temps depending on OAT.

Jim Berry
RV-10
 
Hello Mike.

I do have one of these on my -10 and it does work very well. I am located in the northern US and gets cold here. Went up on Wed night and and had the cooler almost completely closed and definitely helped. I also used the electric servo.

Currently do not have a chart, but going up today, can tell you the difference with it fully open and fully closed. The temp here today is forecasted 34 degrees f.

Brian
 
Butterfly Valve Servo

I really liked the TWC setup for valve actuation with the linear Firghelli servo, very elegant solution. In the end though, I felt that having the actual servos up front in the engine compartment wasn't what I wanted, particularly for the heater valves. Instead, I used Futaba R/C servos aft of the firewall actuating push/pull cables for both heater valves and oil cooler valve. To control the servos, I used the drivers from Perihelion designs. These drivers are nice because they have pots to adjust both servo throw and endpoint, so you don't have to futz with the cables to fine tune valve movement. Works well, but I'm not flying yet...
 
Don't know, but...

Should the vernatherm not prevent oil flow through the oil cooler below set temp? Similar to how thermostat control liquid cooled car engine temp in all OAT conditions.
Johan
 
Michael,

I have a nonstopaviation.com butterfly valve controlled by a standard pull/pull cable. Works just fine.

bob

p.s. I hope you are doing better in your Phase I or whatever the test phase is called in Switzerland than I am. This is the second weekend in a row that wind and weather will keep me grounded.
 
The vernatherm is a bit different than a temp valve in you auto engine coolant. The vernatherm closes when the oil is hot to force oil through the oil cooler. Otherwise it is open to allow the oil to bypass the cooler and return to the engine. It is essentially a bypass valve. There are 2 benefits to this approach. One is that the oil is always circulated in the cooler to some extend preventing congealing. The other is that if the oil cooler path is clogged somehow it won't stop the oil flow to the engine.
 
Thank you everyone for your feedback. I will go for the valve.
@Bob November is quite a bad time for test flights here as well usually fog or low ceiling like 2500ft today and a gusty wind. Waiting for December when it will be colder and blue sky's and snow covered Alps.

Regards
Mike
 
Michael Wellenzohn said:
Thank you everyone for your feedback. I will go for the valve.
@Bob November is quite a bad time for test flights here as well usually fog or low ceiling like 2500ft today and a gusty wind. Waiting for December when it will be colder and blue sky's and snow covered Alps.

Regards
Mike
Click to expand...

Sounds like we are having similiar weather. When the wind is calm, it's IFR. When the wx improves, it's gusty.
 
I just wanted to give feedback to the group. I installed the TCW butterfly valve and the actuator. It can be done easily. Today I went up with 5 degrees Celsius OAT on the ground and it took about 15 minutes until I reached 165 Fahrenheit at about 1000 RPM and the valve closed. Up at 4500 feet we had -6 Celsius and the valve worked fine. I was able to control the oil temp very precisely and let it settle at 186 Fahrenheit at 24 square. The valve was about 27 degree open, assuming that the 10 dents in the control knob equate to 9 degrees valve turn per dent.
I still like the experimentalgoodies.com idea and they will soon have a products ready which will take oil temp data right from the EFIS to control the valve.
Mike
 
oil cooler

I wanted to get a shutoff valve controlled from the cockpit, but I block of my oil cooler completely and the oil still will not get over 160F. I even took the cooler out of the circuit to no avail. Lycoming had no idea what to do. I plan on making inserts for the inlet holes in the cowling to block off some air. My CHT remain very low even in the summer. Never over 335 and one is always 255-285. Any suggestions?
RV-6 O-320-D1A
 
49clipper

Thanks, bill, but I put on all new transducer/sensors from GRT when installing my new EIS4000, and no change.
Jim
 
I too have always had low oil temps on my IO-360 with the standard oil cooler and cover it up completely in the winter to get 160 degrees. My transducer read hangar temp so i felt it was reliable but i pulled and tested in boiling water to be sure.
 
winter ops

I'm sure there are other threads ( maybe dozens) but has anyone closed off the OUTLET of their cowl? Seems it would have the same effect, without nasty duct tape or the turbulence of a partially covered inlet....it would just slow the speed, and lower the volume going thru, right?

not sure it would help the oil cooler as much as covering it directly.
I would also like to try a butterfly valve, but have the baffle mounted cooler, so am trying to thing of the easiest retrofit.........
why wouldn't it work to put a plenum on the BACK of the oil cooler, ending in the valve? In summer, the hot air wouldn't blast my firewall and battery, and winter, it would be a nice short throw cable or rod thru the firewall ( assuming that servos etc. are a little beyond me).
 
Butterfly Valve

This was the first year I had the nonstopaviation butterfly valve on my -10 using a push/pull cable.

In the winter it works great. I can warm up quicker and keep my oil at any temp I desire. Without it I would typically only be able to get my oil to the high 160's.

In the summer though I have struggled to keep my temps low with the valve open. My -10 usually runs great in the hot summer and doesn't get warm. I have my alarm set to warn me at 220 F. I might hit that a couple of times a summer when I am climbing for a long time. With the installed valve, I was hitting it on almost every flight. It took longer than normal to cool back off once I was at a cruise altitude. I took the cowl many times to ensure the valve was fully open. I thought it could be flexing with the force of the air but seems very stiff. That is one thing I like about the TCW system, it is a much stiffer system. If I don't find anything I will have to take it out each spring and put it back in the fall.
I know others do not have this problem so I am starting to look at other possible causes.
 
nonstopaviation valve

I too have the nonstopaviation oil cooler valve installed. It works great and in cold weather I can keep the oil temp at or near 180 degrees F. A nice feature is that engine warms up much more quickly on very cold days, I often leave the valve completely closed for take off and initial climb. I have my alarm set to 205 degrees F so if I do forget I re-adjust the push pull cable knob to about half way in and the temp almost immediately begins to go down.

For the summer time, of course, the valve is wide open. The alarm remains set to 205 degree F. At that value I do get the alarm occasionally in a long climb out but I don't seem to have the problem Scott describes. Having said that I typically set my enroute climb speed to 120kts.

If my temperature climbs above 210-215 (this happens rarely) I will ask ATC to level off until my the temp moderates and then continue the climb.
 
If i recall correctly, for me, the nonstopaviation valve added about 10F to oil temps in the wide open state vs without the valve. Thus the valve does add some resistance even when wide open.
 
Like Scott and Ivan, I have the nonstop aviation valve too. When I was flying the other day when it was in the lower 20s on the ground, I closed the valve about half way and was able to keep the oil temps at 185.

Jae, several things you may want to consider. Do you have the Airflow cooler? Did you install the plate in the cooler mount to better distribute the airflow? Also, what is the orientation of the valve?

If you have the divider plate installed and the valve is orientated fore/aft, air may be restricted to all of the cooler depending on the setting. In talking with Geoff Combs before installing mine, I orientated the valve left/right so that the airflow would be more constant in both halves.
 
49clipper

Perry,
I tried blocking off a little over 50% of my cowl outlet and it only helped increase the oil temp 5 degrees. I think my next step is reducing the inlets size. I think that will work for sure. I intend to make winter inlets that I can fit for use in the winter.
Jim
 
rleffler said:
Like Scott and Ivan, I have the nonstop aviation valve too. When I was flying the other day when it was in the lower 20s on the ground, I closed the valve about half way and was able to keep the oil temps at 185.

Jae, several things you may want to consider. Do you have the Airflow cooler? Did you install the plate in the cooler mount to better distribute the airflow? Also, what is the orientation of the valve?

If you have the divider plate installed and the valve is orientated fore/aft, air may be restricted to all of the cooler depending on the setting. In talking with Geoff Combs before installing mine, I orientated the valve left/right so that the airflow would be more constant in both halves.
Click to expand...

Hi Bob, sorry for the late reply. I finally got around to your suggestion of re-orienting the butter-fly valve. I had mine originally oriented so that the butterfly plate would rotate along the horizontal axis. I reoriented the rotation axis to be vertical instead. It turned out to be an even easier cable routing than before, too.

Only have one test flight in so far, but a BIG difference. Thanks again for the suggestion!

Also, i still have the original oil cooler. I hope your test flying is going well now that spring is here!!! :D:D:D

Jae
 
2006X vs 2008X oil coolers

While on topic of oil cooling, can anyone give their experience comparing the two sizes of oil coolers? I know than Jan Hanekom has installed the 2008X using the stock Vans cooler mount with some minor mods. I was planning on installing the 2008X with the Nonstopaviation valve. It would seem to me it is easier to plan for warm weather flying (larger cooler) and control oil temps with valve when in colder environment.
I believe the 2006X has 13 rows and the 2008X has 17 rows.
Thanks.
Johan
 
My butterfly is up by cyl #6, shaft axis of rotation vertical, standard Van's engine/oil cooler and Aeroshell 15W50. When flying around 0F OAT with damper closed, my oil temp max is about 165F. No problem keeping oil temp under 210F in the summer months with a little higher airspeed in the climb.

At 65% LOP cruise with OAT of 70F and above my butterfly is always open. I usually see oil temp between 180-185F on most summer trips.
 
Last edited:
Confused

Wayne Gillispie said:
My butterfly is up by cyl #6, shaft axis of rotation vertical, standard Van's engine/oil cooler and Aeroshell 15W50. When flying below 30F with damper closed, my oil temp max is about 165F. No problem keeping oil temp under 210F in the summer months with a little higher airspeed in the climb.
Click to expand...

Wayne,
When you say "damper closed", does it mean the "butterfly" is closed and has shut off airflow through oil cooler? At 165F should the vernatherm not prevent significant oil circulating through oil cooler? If this is correct, then it appears you don't need an oil cooler in winter?
My stock production aircraft (Socata TB10) with O-360 engine runs about same oil temp winter and summer and has no airflow control mechanism, so I assume this is all vernatherm controlled.
Thanks.
Johan
 
Last edited:
Dorfie said:
Wayne,
When you say "damper closed", does it mean the "butterfly" is closed and has shut off airflow through oil cooler? At 165F should the vernatherm not prevent significant oil circulating through oil cooler? If this is correct, then it appears you don't need an oil cooler in winter?
My stock production aircraft (Socata TB10) with O-360 engine runs about same oil temp winter and summer and has no airflow control mechanism, so I assume this is all vernatherm controlled.
Thanks.
Johan
Click to expand...

I corrected that to 0 F OAT.

There is always a small amount of oil flowing through cooler to help prevent oil congealing. The air flowing around the outside of sump and oil cooler carry some heat away too. The more oil I have in the sump, the cooler my oil temps run. The higher I fly, the higher my oil temp and cht's run due to lower density air/higher AOA, especially with low lapse rate.
 
You must log in or register to reply here.
Back
Top