Avcon 180hp oil temps

[flyboy122]

Hi All,

I finally got my plane back in the air last night and started to break in the shiny fresh o/h'd Lycoming under the hood. Governor was a little wonky (not sure on that one), but otherwise it ran great. My bigger question was on oil temp. It stayed rock solid at 170 deg. Lycoming recommends 180-225 deg as the normal operating range, so this seems a bit low. I also figured it would be higher for the break in. That being said I have almost no time in these aircraft, and am not sure if that's just how they are, or not? What do the rest of you guys normally see for oil temps on the Avcon conversions? I'm running Shell mineral oil, straight 40 weight. Ambients were about 60-65 and I was at about 2500' agl. Pressure was rock solid at 70psi.

Thanks,
DEM

[DaveF]

My Avcon runs within a few degrees of 180 all the time, except when I'm doing a lot of landing practice on a hot day, then it'll go to 190. Those are the same temperatures it ran before the overhaul with multi-vis oil and immediately after with type M mineral. I'm now back to multi-vis and no change. I have two temperature gauges: The stock gauge and a probe on my JPI engine monitor. They agree.

[rupertjl]

The vernatherm that controls the oil flow probably is just opening closer to 170 than 180 deg F. We've seen that at the factory while dyno and production test running the engines. We've seen the variations in temps and have mostly attributed it to the production variance in them. I forget what the print calls out as the acceptable range, if I have time I will look.

[ghostflyer]

Have you checked your gauge if it measuring correctly. A good check is to put the sender unit in boiling water . Water boilers at 100 degs C or 212 degs F. Plus what size is you oil cooler . There is 2 sizes around . I put a larger size on due to the adverse climate that I live in ( fly in) .my temperature hovers around 170 to 185 .

[flyboy122]

Thanks Guys,

I calibrated the gauge tonight, and it's spot on. I also pulled the vernatherm and checked it's length against the old one in the off chance it was defective or wrong p/n. Same. I didn't temp test it to see when opens. I may try the old one just for the heck of it, but it sounds like these generally run cool so at least I'm in the ball park. I was running 24 square (75%) and full rich, so it wasn't like I was working the engine real hard either.

DEM

[Blue4]

DEM:
Avcons have a tendency to run cool with respect to oil temperatures. I ran through the same concerns when I first bought my airplane. After testing & replacing the oil temperature sensor/gauge, it still runs cooler than Lycoming would prefer.

I think the oil cooler is probably unnecessary 90% of the time with these conversions.

It is what it is. You can operate the airplane in such a way to run your oil temperature up to eliminate contaminants, but that is probably offsetting the extra wear of running the engine that way. So my recommendation would be to frequently change your oil and find another worry for your airplane.

I know I have plenty! I got over that one though.
-S

[ddr36d]

DEM,
I have the Delair conversion on my 170B & it runs cool also. When I had a fixed pitch prop on it I covered half of the oil cooler in the summer & all of it in the winter to get to 180 degrees. Now I have a 80" Hartzell on it which makes the engine work harder. I can get 185 -190 degrees in the summer without covering the cooler & in winter I cover half of it & get about the same. I made the covers out of .032 2024T-3 aluminum & attached it to the rear baffle with the same bolts that hold the oil cooler. I use the 170B for pipeline patrol so I run it at a fairly high power setting, usually 2400 RPM & 25 " MP.
Don

[Lopez]

My Lyc ran cool too, so I put a plate in front of the oil cooler and that brought it up to proper temps. Sometimes in the summer it runs a wee bit warm, but not out of limits by any stretch.

[flyboy122]

Thanks guys. Sounds like it is what it is. I did double check everything just in case, and flew in some higher ambients the other day and noticed a bit higher temp, so I believe it's all working as it should.

Based on that, I'm assuming I'll need a block off plate for winter. I seem to recall Dad telling me block off plates should be on the back of the cooler, not the front, but can't quite remember. Thoughts?

DEM

[GAHorn]

The purpose of the verniatherm is to regulate the oil temperature similar to a thermostat in your automobile cooling system.
If things are working properly, the oil cooler will not open up for cooling until the oil is sufficiently warm to warrant cooling.
(Although winterization kits are designed to better accomplish warmer engine temps and may be necessary in really cold wx.)

[flyboy122]

The purpose of the verniatherm is to regulate the oil temperature similar to a thermostat in your automobile cooling system.
If things are working properly, the oil cooler will not open up for cooling until the oil is sufficiently warm to warrant cooling.
(Although winterization kits are designed to better accomplish warmer engine temps and may be necessary in really cold wx.)

I did some vernatherm research when looking into the appropriateness of my oil temps, and as I understand it never fully blocks off the oil cooler, just regulates from a little to a lot of flow. Will it close enough to keep temps up in winter?

DEM