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High Oil Temperature

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As it has warmed up in SoCal, my RV12 Rotax 912ULS oil temp has gone into yellow territory (235+) on the Skyview during climbs. I typically shallow out my climb as much as possible and increase my airspeed to cool things down, but a 50-100 fpm climb does not get me to altitude as planned. I've even experienced this during night flying, after the air temp has dropped down from the daytime high.

Has anyone else experienced this phenomenon? Does anyone have a remedy or suggestion?

Thanks.
 
Hi Thom,
I'm not familiar with the plane you bought nor the original builder.
Might be helpful is you can tell us a little more about your plane, e.g. kit # and was it built E-LSA or EAB? When was the first flight? Has it flown during the hot season before? Any problems? How many hours on it now? Do you have any of the engine data log files that you could search for earlier high oil temps? Can you measure or estimate the clearance between the back of the oil cooler (when mounted) and the front of the muffler? Really I'm kinda "grasping at straws" here but any info might be helpful to eliminate some possibilities and perhaps suggest others. Hopefully some of the other hot weather fliers will chime in with their experiences. I have flown my 12 here in North Alabama in 90+ degrees ambient without issues, however during the build I modified my lower bowl cooling duct to move the oil cooler 1 inch forward and away from the muffler.
 
My apologies, I should have suggested earlier that you do a search for "oil temp" in the RV-12 forums. What I just found suggests you don't have much of an issue, but you'll want to be sure you're using the correct oil. Recommend you do the search and read the posts for your own info and enjoyment.
Be safe,
DW
 
Thom -- In my experience and that of others, the 912ULS tends to run hot during high ambient temp / high power operations. See your PM. -- David
 
Thom -- In my experience and that of others, the 912ULS tends to run hot during high ambient temp / high power operations. See your PM. -- David

Agree, but ... I've never had my oil temp out of the green, even here in our sometimes very high Florida temps, easily in the mid 90s this time of the year. I have the old muffler that's fairly close to the oil cooler and it's all unmodified down there. Just as a precaution, I'd check to make sure the oil cooler is clean & unobstructed. Don't know how to check whether it's unobstructed internally.

Don't know where you are in So Cal but we used to live in San Diego and no way would any of the temps we saw there be a problem. [Sry, just saw you lived in Escondido - we were in Rancho Bernardo ...]
 
There are a lot of different factors that can influence oil temperature in hot OAT conditions.
Incorrect prop. pitch, and can have an influence. As well as the build of the airplane (I am aware of RV-12's that in a quest to have more spinner to cowl clearance, the cowl was installed excessively far aft which actually resulted in contact between the oil cooler and muffler)

There is also different temperature personalities with different engines.... some run hotter than others. I know if instances where an engine was removed and a new one installed using all of the same components from the original, and the oil temps instantly jumped 10-15 degrees from what they would have been previously at the same OAT condition.

The main operational concern is when in continuous cruise flight, does the oil temp return to the green range? Rotax specifically allows short duration operation in the yellow for a climb.
 
Scott -- I sure do wish Van's would sell retrofit exhaust stacks that would allow legacy-builders to reposition their old-style mufflers further aft like the current muffler set-up. I prefer not to have to buy a new muffler plus stacks to accomplsh this enhancement. -- David
 
Scott -- I sure do wish Van's would sell retrofit exhaust stacks that would allow legacy-builders to reposition their old-style mufflers further aft like the current muffler set-up. I prefer not to have to buy a new muffler plus stacks to accomplsh this enhancement. -- David

It has been mentioned before, but it is not my decision to make.
There are specific reasons for not selling just the pipes.... many that I probably don't even know about.
There is a new company president.... can't hurt to try asking again.
 
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