EJ25 oil temps

[StanFoster]

Now that I have my thermostat problem fixed...my water temps are up around 190 instead of 130. What is the max reading you guys run on your oil temps? I want to set my red light to a level a little below the max.


My oil temps were running a cold 190 before my thermostat was fixed....and now are running 245-250.


Thanks

Stan

[mceagle]

Oil temps should be within the range of 100*C to 125*C (must be over 100*C or 212*F to boil away any contaminates) It sounds as though you are within that range.

[automan1223]

Now that I have my thermostat problem fixed...my water temps are up around 190 instead of 130. What is the max reading you guys run on your oil temps? I want to set my red light to a level a little below the max.


My oil temps were running a cold 190 before my thermostat was fixed....and now are running 245-250.


Thanks

Stan


Stan, I do not know why you think the 190 is cold. It is near perfect. 180-200 is optimal. For the amount of money you paid for the kit, tell me that you do not have an oil cooler in the crate ? Engine longevity is directly related to engine operating temps....... Oil longevity is also directly related to oil temps. Boil the oil and you boil the additive package right out of the mix.

Seriously by the summer time you will be going atomic with oil temps. I could not disagree more, with oil temps above running above 220f. We are running our engines at extreme rpms. We need cool oil to keep the rings on the pistons from carboning up and burning out the seals etc, etc, etc.

Now if Sparrow is not including an oil cooler I would not wait to add one. Even a small one is better than none.

Jonathan

[Papa Smurf]

40F above jacket water max is a good target.

[StanFoster]

Jonathon: The oil cooler is optional. After getting my water temps where they should be......this is why I posted that question. I now see that I will need to order an oil cooler. :)

Of course when the 90 degree days get here....that oil will be much warmer yet.

Thanks for the post......


Stan

[Chopper Reid]

Sorry Stan, I disagree with you re water temps, you had it right, now you have it wrong ! Once you lifted the water temp, it has automatically lifted the oil temp and once you get in summer, you could well find the oil temp is too high!!

The high water temps in the car were to operate or keep the vehicle exhaust emmisions in range. Now the motor is no longer in a vehicle, that high temp is no longer needed for emmision controll. The cooler a motor runs, the longer it will last !! and the more reliable it will be !

There should be no need for an oil cooler in a gyro unless the motor is turboed or the motor has been modified to produce high horsepower !! or you are going to fly at full throttle for hours at end !

[PW_Plack]

Stan, you're on the upper limit of oil temp.

My Cessna 172 owners manual defines 245F / 118C as the upper redline for oil.

From a RV-6/Subaru turbo conversion article in 2005 Kitplanes magazine, written by race engine builder Ross Farnham: "Maximum oil temperature is 248F, max coolant temperature 230F and max intercooler discharge temperature is 131F."

I've seen a wide range of aircraft owners manuals place lower limits for oil temp at takeoff of 100 - 122F / 38 - 50C. Colder, and oil pressure can be above limits, and oil flow will suffer.

Oil coolers aren't just for turbos. Most police cars, cars and trucks equipped by the factory for trailer-towing, and many other high-load applications come with aux oil coolers standard.

I've read specs on synthetic oils which claim much higher max temps. Mobil 1 can supposedly run at 350F without much degradation, but it will also do little to aid cooling if you do.

Oil doesn't have to reach water's boiling point to get rid of water, but it needs to get well above ambient air temp. If you heat a pot of water on a stove to 180F/82C, steam will rise, and the pot will evaporate rapidly, even though you haven't reached the boiling point.

I believe the right combination is to have both coolant and oil running near what the design engineers targeted, and that means an oil cooler on an aircraft conversion. Running a Subaru at a coolant temp of 130F gains no margin for hot days, because the 190-degree thermostat will be wide open before the water ever boils. Running cold doesn't just increase emissions, it also increases fuel consumption.

I'm not convinced that every popular "tweak" to the Subaru is an improvement over the opinions of the engineers who designed the thing.

[Chopper Reid]

Paul, the increase in fuel consumption is nearly impossible to measure.
Yes, there is no reason NOT to install a oil cooler BUT why when the Subaru car with a 2.5 doesnt provide one ?
I have had a few engines in my day and there is absolutely no doubt in my mind that a cooler running engine will last a lot longer than one running hot !

[Chopper Reid]

Of course, the radiator must be suitable for the application as well.

[PW_Plack]

Brian, the car never runs the engine at 80 per cent of max power, or 80 per cent of max RPM for hours at a time. A Subaru Forester cruising at 100 km/h probably requires 10 per cent power.

Aircraft use runs a much higher duty cycle.

Subaru includes oil coolers on cars sold to road racers, and aftermarket vendors like these guys (http://www.i-club.com/forums/showthread.php?t=128724) sell them as well:

While track-side tuning Brian Locke’s WRX US Touring Car, the WRX’s ability to sufficiently cool its oil when operating in extreme conditions became glaringly apparent. Even in cool weather with moderate cycling, the factory system seems stressed, resulting in dangerously high oil temperatures (this is probably why the Spec C’s come with an oil cooler from the factory).

After testing various solutions, we finally selected a setup that is more than capable of dealing with the stress of road racing. With the Gruppe-S Oil Cooler, the racing oil temperature was reduced a consistent 40 degrees F, even in 110 degree + temperatures of Arizona, as proven with our data logs.

[Canadian Rhino]

It seems to me that even before fuel injection and smog controls everyone was still using 190F thermostats! The oil will always be a bit hotter from being sprayed on the under side of the pistons.
The old oils of yesterday would start to oxidize at around 250F but todays oils can withstand much higher temps without much effect.
Even on a hot day the oil temp shouldnt raise by much as it is still being cooled by the water jacket mostly and the engine isnt producing as much horsepower and heat because the ecm wont put as much fuel into hot air.
Just my $.02;)