Operating Oil Temperature

[N3787T]

The oil temperature in my O-200-powered F19 runs about 220 F in cruise, even at moderate ambient temps (e.g. 38 F OAT).

The Continental Overhaul Manual for C75, C85, C90 and O-200 Engines (page 12) states that maximum oil temperature limit is 225 F. However, the F19 Approved Flight Manual (Page 3) states oil temperature maximum is 240 F. Likewise, the Cessna 150M Pilot's Operating Handbook (page 2-4) lists maximum oil temperature of 240 F.

For those flying behind one of the little Continentals: what is your oil temperature under typical operating conditions?

Cheers,
Doug

[mike lutz]

My A-65 runs around 160 -180 degrees when air temp is anywhere from 70 to 90 degrees outside. That's at cruise rpm. 190 in long climb. However very seldom climb very long on most flights.

[sully]

From the TCDS.

NOTE 1. Maximum permissible temperatures:
O-200-A,
Cylinder head 525° F
Cylinder barrel 290° F
Oil inlet 225° F. (Straight mineral)
240° F. (Detergent meeting MHS-24, See NOTE 6)

NOTE 6. Detergent oil meeting Continental Specification MHS-24 required when using 240° F oil inlet limits except
during break-in period. Follow manufacturer's instructions for break-in or when changing oil types. Marking
or placards prescribing use of Continental Specification MHS-24 oil only shall be installed on or near the oil
filler on installations using 240 ° F oil inlet temperatures. Lubricating oils qualified under SAE-J1899 or
J1966 are considered qualified under CMI Spec MHS-24

[astjp2]

Mine run 230

[N3787T]

Thanks for the replies, and, Sully, thanks for the reference to the Type Certificate Data Sheet. I see now: there are different temp limits for straight mineral vs. ashless dispersant oil. Good to know, since I'm running straight mineral oil after a top overhaul.

[Ragwing nut]

oil temp is going to be higher for the first couple hours until the rings seat. Mine never ran that high that I recall. Is your lower inlet baffle in good condition and tight?

[TC747paul]

My C85-12 runs about 130 F over ambient, i have the spin on oil filter and luscombe exhaust-which is not insulated. the engine is running great, but i am still trying to reduce that to 110F or so. the Tcrafters at my airport all try to run their 65 HP at 100F over ambient

[astjp2]

This thread sould have started: I am breaking in new cylinders, what should I expect my oil temps to run?

[PA1195]

Confirm the accuracy of your gauge - put temp probe in boiling water for example. Until the piston rings seal and piston to cylinder friction abates some temps may be higher. Is there more oil fume blow-by out the breather now as well? If so that piston leakage can heat oil more than later after break-in. Any idea as to all cylinder heat or exhaust gas temps, particularly if they are uniform or if one or more hotter? Are the cylinder baffles tight and the upper engine to cowl spaces sealed in flight?

Gary

[N3787T]

"This thread sould have started: I am breaking in new cylinders, what should I expect my oil temps to run?"

Could have, but oil temp ran high before the TOH, and the major OH before that. It's come down a couple degrees in the several hours STOH; I don't expect it to change much more. The cowling is sound and the baffling is newish. For anyone flying an F19: What oil temp do you see?

[Ragwing nut]

I pretty certain mine was never over 200 or was close to it. I don't like oil temps hovering 210 plus. I'm referring to the baffle that is underneath the spider that directs air from the lower inlet directly to the oil tank. Ercoupe had an issue with oil temps and made a baffle that fit around the tank. Univair makes/made that baffle but its not cheap.

[PA1195]

The oil temp gauge needs confirmation as to temps near boiling. Without that the indicated values are only a relative guess.

Run the engine 75% power plus...redline or near isn't a concern if you want tight cylinders and good compression. Check the current leak down compression during the break-in and note any quick step increases for example.

Is a flat propeller capable of over redline ops installed? Load via coarse/high propeller pitch is critical on break-in ops.

Most engines with flat fixed pitch props never see enough BMEP and load when new and blowby for the rest of their lives.

Gary

[astjp2]

I pretty certain mine was never over 200 or was close to it. I don't like oil temps hovering 210 plus. I'm referring to the baffle that is underneath the spider that directs air from the lower inlet directly to the oil tank. Ercoupe had an issue with oil temps and made a baffle that fit around the tank. Univair makes/made that baffle but its not cheap.

Mike, do they make it for the Taylorcraft or the Ercoupe? The F-19 doesnt use it. I wonder if it because the long mount and opening being bigger on the bottom.

[Ragwing nut]

Mike, do they make it for the Taylorcraft or the Ercoupe? The F-19 doesnt use it. I wonder if it because the long mount and opening being bigger on the bottom.

Its an ercoupe part. The F-19 cowling should not have a bigger opening than standard bc12-D. Its just longer. The F-21 has a bigger opening. The back of the cowl should also have a lip to create a low pressure area at the opening to help pull out of the cowling.

[N43617]

what nose bowl do you have the f19 style with no lower intake. that is what i am running and i feel my runs a bit hot too. i would bet most people running lower intake cowling have lower temps as well. my 85 stroker runs 210-220. most continental powered ships have a lower inlet