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adding oil thermostat

seagull

Well Known Member
Has anyone added the oil thermostat without buying the Aircraft Specialties $799 "kit"?

I see the Thermostasis device on Spruce is $196.75, I assume the additional $600 is fittings and hoses, are these parts available elsewhere? My engine already has Teflon oil lines.

I do support Steve all I can but $799 is more than I can justify based in So California.
 
OIL THERM - -

I designed the first one. Aircraft Specialty fairly much copied my design. No problem. I used Aeroquip hose. Has worked well for 10 years. I think I posted pics way back when. Thermostasis is the place to go for the actual therm. If you want to do the work, you can save a fair amount. Please don't ask me to give you exact specs. I just buy the hose in bulk, and reuse the fittings.
 
I am very capable of doing the work and fitting it. The crimps and tool are what I am unsure of.
 
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Oil Therm - -

I used hose barb fittings. Just cut old hose off and reuse fittings. I did put hose clamps on each fitting. Works very well. 1/2" hose as I recall.
 
Barbs…

FYI, I’m avoiding barbed fittings with hose clamps at all cost, especially in an airplane.

I’ve personally seen two engines get trashed when the hose just slipped/popped off of the barb. One event nearly killed a friend. They do loosen over time, as the hose compresses, heat cycles, etc…

Go with real threaded fittings, much safer and more reliable.
 
John B., were the original oil hoses on your RV-12 rubber or braided stainless steel (probably Teflon lined). My oil hoses have crimped ends, no clamps. I assume that my fittings are not barbed.
 
Jim, do you have one? Your thoughts?

No, my RV-12 is early SN with oil cooler located close to front of muffler. If anything, I have to watch oil temps in summer. On hottest days, I will see 240F (lower yellow arc) in extended climb. Temp falls back nicely in cruise. I use 100% synthetic oil, so excessive temp is not a problem.

No need for me to add Thermostasis. Engine warms quickly even in winter when I use Engine Preheat. I preheat engine for 3 hours and when I arrive at hanger the EMS shows oil at 80F. Engine burps quickly confirming warm oil.

Rotax 912 has enough hoses to choke a horse already, so I prefer not to add any more complexity or points for failure.
 
Hose barb concerns - -

When I change the hoses, I can't imagine how they could come off unless being pulled on in operation. I have to cut them off. They seem to 'weld' themselves to the hose barb. If you have ever tried to put 1/2" hose on a hose barb, it makes sense they don't come off easily. Keep in mind, all the oil therm hoses are in vacuum, no pressure.

An oil therm cuts warm up time in all weather. Second best mod I have made after the Heater Damper Door mod I designed.

Joe, I don't recall what the original hose were made of. Seems like they had wire in them.
 
I designed the first one. Aircraft Specialty fairly much copied my design. No problem. I used Aeroquip hose. Has worked well for 10 years. I think I posted pics way back when. Thermostasis is the place to go for the actual therm. If you want to do the work, you can save a fair amount. Please don't ask me to give you exact specs. I just buy the hose in bulk, and reuse the fittings.

We worked with Rob R, John P, and Kim K on our original Thermostat installations and went through a variety of different configuration options before settling on the current location for the thermostat which is in a different location than JBPILOT put his. We initially evaluated the position of the thermostat on the firewall and with the help of beta testers determined it was not the optimal location for an easy, low maintenance, drop in installation.

Oil thermostats have been available and have been installed on the Rotax 912 engines for a long time. There is nothing magical about the installation other than you are essentially inserting a thermostat into the middle of the oil system which changes it from a 3 hose setup to a 5 hose setup.

Since nearly the beginning of the RV12, VANS has been putting Teflon oil hoses on the RV-12. The ONLY disadvantage to a high quality conductive Teflon oil hose is cost. They are significantly more expensive than a piece of rubber hose and a few barbed fittings. There is good reason for that. There is also a reason that VANS and other manufacturers have moved away from Rubber hoses.

I have to see that from personal experience, I love the oil thermostat in our RV-12. Warmup times are reduced and temperatures in flight are nice and stable. Then again, we are in WI...... enough said! :)

Steve
 
FYI, I’m avoiding barbed fittings with hose clamps at all cost, especially in an airplane.

I’ve personally seen two engines get trashed when the hose just slipped/popped off of the barb. One event nearly killed a friend. They do loosen over time, as the hose compresses, heat cycles, etc…

Go with real threaded fittings, much safer and more reliable.

This is very sound advice. In addition, there are very good reasons not to use rubber hose in aircraft engine installations.
 
when i built my hawk with a jabiru 3300 i installed a thermostat i bought from one of the auto parts houses. it was a ''shunt'' in the loop to the oil cooler. i used it for several years before a thermostat was specifically made for the jab which mounted under the oil filter. my installation worked perfect, temp. was always right on.
 
Oil Therm - -

I understand those that want the best hoses for any aircraft application. I will only report that I changed my Aeroquip rubber hoses at 10 years. I have nearly 1,500 hours on my plane. I cut the hoses off and cut them apart to see what they looked like inside. Flawless would be the best word. It is a real job to push the hoses on a 1/2" barb. Then with screw clamps, they are safe. If one got very close to an exhaust pipe, a wire braid could be better I'd assume. Do what you feel is best for you.
 
fwiw i have used ''bulb flare'' fittings for hoses and found that i am able to remove the hose without damaging the hose. anyone have any insight about these fittings?
 
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