Pponk with about 30 hrs in it (running mineral oil)

Oil temps are 20 to 25 degrees F higher than they used to be with my O 470R
205 F to 218 F while in cruise , even with low settings and running rich or higher settings, leaned.
This is reading before entering the oil cooler with a JPI probe and instrument.

The original oil temp probe was just replaced with an Aerospace Logic probe and gauge, this probe is after the oil cooler, where the original was.
Shows about 160F
What this shows is that the oil cooler is doing its job.
My mechanic said to check the baffling, since CHTs are below 380F and EGTs a tad below 1500F I am not too sure this could be related to baffling.

Pponk and Continental both say oil temp is on the hot side but since it is less than 240F should be fine.(I am not too happy with this since those temps will rise even more on a hotter day and climbout of a confined place.)

Any ideas are welcomed.

I am just hoping that once I change to AD in just a few hrs, oil temps will drop.

I don't think changing oil will help. It could be just part of the break in, are you using any oil? Did CHT'S drop and stabilize? The baffling is very important for keeping CHT's down. If you have hot cylinders your oil will get hotter also. How many degrees can you lean before you hit peak EGT? Timing check?
DENNY

I changed the oil 10 hrs ago and I have no need to add any yet.
CHT dropped and are stable now.
The way I lean is I start pulling the mixture until the hottest cyl is just below 380F.

So all CHTs are below 380 during flight.

Was the oil cooler flushed?

Oil cooler overhauled at the time of the Pponk conversion.
Also its working real good JPI probe shows 215 F before the oil cooler and Aerospace Logic probe after the oil cooler shows 165 F .(This probe replaces the original oil temp probe)
So the oil cooler is doing its job.

What I was looking for with the leaning question is based on EGT. Basically from full rich can you raise you egt 150 degrees before you hit the first cylinder to go lean of peak?
DENNY

Check your vernatherm. It’s a thermostat that diverts your oil either thru the oil cooler or dumps it back into the pan. If it’s not doing it’s job right your oil wil run hot and your pressure will run low as a result. Mine did that shortly after the Ponk rebuild . Take it out and put it into a pan of water heat it up and watch it malfunction.

Oil pressure is stable at 57 psi, does not drop when oil temp gets hot though.

Is that 57 PSI at cruise? If yes, is that a bit low?

Easy to change pressure with adding a washer or on mine, an adjustment screw with a lock nut on the oil pump.

twflyer wrote:Is that 57 PSI at cruise? If yes, is that a bit low?

Pponk Oil pressure green range, normal operation is between 30 psi and 60 psi, so 57 psi is pretty good actually.

Continental takes the oil pressure reading at the far end of the system, so it scares the Lycoming crowd (pressure taken at front of system) when we see it that low.
DENNY

Changed to AD oil Aeroshell 100W.
Same high oil temps (compared to before).

I am running 9 quarts and Camguard

Will add 1 more quart to see if that helps, but I think is going to be blown thru the breather tube.

So the 240 F redline for the oil temp in this engine is taken after the oil just comes out of the radiator?
This is where the original probe was.

I’m not sure you actually have a problem. I would look up where the oil temp probe is depicted for your engine on your airframe and the designated temp range.

As long as it is below 240 F there is no problem, but wondering why it runs 25 F hotter oil than before the conversion ,and also hotter oil than most Pponks out there.

The O-470 on my 182 with 1300 smoh runs similar temperatures, it’ll be around 200-210 on long flights in the summer. A little concerning at first, but it just seems to be where it runs.

I’ve been flying behind an R1340 quite a bit lately, temps down here are approaching 100 and that thing is always showing to be running near redline. An easy way to check the oil temp is to pull the dipstick and let a little oil run on your hand. If it’s hot and viscous, you’re ok and the gauge is indicating high. If the oil scalds your hand and is runny, it’s time to figure out what’s going on.

Have you checked to see if your probe is reading correctly? Put it in boiling water and see if the temps match. That would be my first check.
It's also possible that your vernatherm is not opening enough. I would also check it.

I removed the original probe and installed a digital STCed one from Aerospace logic, this one goes just below on the back of the oil cooler.
The JPI probe is between cyl 2 and 4, where it has been for about 6 years now.
JPI probe is reading 210 , 215 F in flight

Aerospace Logic probe In flight reads 158 to 160 F no matter what, if the JPI shows 180 or 215 always is just about 158 to 160F

So I am not sure, since I dont have enough knowledge if vernatherm its not opening properly and cooling just a little amount of oil , and that is why is pretty low temp after the cooler or what.
Or it is just how it is supossed to be.
According to Continental the oil temp after the cooler should be between 168F and 178 F.

And mine is just 160 at the most after the oil cooler.

motoadve wrote:I removed the original probe and installed a digital STCed one from Aerospace logic, this one goes just below on the back of the oil cooler.
The JPI probe is between cyl 2 and 4, where it has been for about 6 years now.
JPI probe is reading 210 , 215 F in.

The only place I have ever seen an oil temp probe on a 182, 180, 185 is right under the oil cooler. Your JPI probe is installed where the oil pressure is usually read.
My PPonk motor has the biggest non congealing oil cooler and runs the same temp. OAT will have to be 80+ for me to get 180 oil temp. I can metal tape over the cooler and get the temp up higher.

I know this is an old thread, but just came across it and figured I’d share for posterity or the next person trying to solve this challenge. I went through the same high temp issues when upgrading a ‘53 180 from an O-470J to a Pponk O470-50 a couple years ago, and went through the same questions about vernatherm, etc. “Fixed” each one with no net gain on each subsequent flight.

The cure for me was installation of cowl louvre vents - apparently was getting turbulent airflow inside the cowl due to lack of negative pressure on the bottom drawing air across the cooling fins. Once those were installed, temps were all back to normal and have stayed that way ever since.