oil temp on warmer days

[andre mendonca]

Dear fellows pilots of RV-12,

I live in Brazil, in a city where winter lasts only for a few days, and temperatures rarely go under 50?F. So, most the times I take off in OAT around 80?F. Climbing to flight level the pointer of the oil temperature instrument goes into the yellow line. All other intruments (CHT, oil pressure, coolant temperature) are normal.Then I climb in steps, and as soon as I reach my desired FL, the pointer goes back to the green line and there it remains during all the flight. Some friends of mine here, flying other models of SLA equipped with Rotax 912, told me that they share this same "problem".
Could any of you tell me if is this your experience? Any solution, if necessary?

Thanks a lot!!

[Phantom30]

Originally Posted by andre mendonca

Dear fellows pilots of RV-12,

I live in Brazil, in a city where winter lasts only for a few days, and temperatures rarely go under 50?F. So, most the times I take off in OAT around 80?F. Climbing to flight level the pointer of the oil temperature instrument goes into the yellow line. All other intruments (CHT, oil pressure, coolant temperature) are normal.Then I climb in steps, and as soon as I reach my desired FL, the pointer goes back to the green line and there it remains during all the flight. Some friends of mine here, flying other models of SLA equipped with Rotax 912, told me that they share this same "problem".
Could any of you tell me if is this your experience? Any solution, if necessary?

Thanks a lot!!

Andre,

Not sure when you recieved your engine w/muffler.....Van's has started shipping a muffler/manifold which sets the muffler back away from the oil cooler somewhat that allows for cooler oil temps. Several guys on this forum have modified their lower cowls to effect this same thing. I have not completed my kit yet; however, decided to get revised muffler option.

[RFSchaller]

Flying in Phoenix I face this every summer. I try to do all my preflight checks during taxi, so I only have run up left at the he time I reach the runway. That gives me the lowest possible oil temp for takeoff. Then I climb to about 2500 AGL before my oil temp hits 230F and throttle back to 4800 RPM to let things cool down before climbing further.

[rvbuilder2002]

Rotax does not consider short term oil temp. excursions into the yellow range , to be a problem.

If the temp lowers back into the green after leveling off in cruise flight, you are fine.

[Sink]

Oil temps on a warm to hot day that go into the yellow are not an issue for short term operation. The yellow is just there to get your attention and make you pay attention to a rising oil temp. Many see 230-245F on hot day climb outs, but go back down once leveling off. On a warm to hot day at cruise oil temp usually runs between 212F-225F. If you were flying on a 105F day and depending on your rpm your level cruise temp could be at 230F. Different aircraft applications and under the cowl configurations has an affect here and prop pitch definitely plays a part. Over pitching can cause high oil temps quickly and keep them up there. If they climb to let's say to 240F+ and never come down then it's time to find out why.