oil cooler

[darenlhr]

I have a 90 on my pa11 with oil temp issues has anyone installed a oil cooler?

[mvivion]

[QUOTE=darenlhr;843628]I have a 90 on my pa11 with oil temp issues has anyone installed a oil cooler?[/

Do you have the blast tube blowing on your oil temp bulb?

MTV

[Waldo M]

What mvivion said. When we switched from an A-65 to a C-90 on our PA-11, I was able to get the conversion drawing from Piper. I call it the poor man's oil cooler. [The A-65 doesn't need the extra cooling]

Part of Piper's C-90 installation involves an aluminum box covering the oil screen housing that accepts an air drive scat tube for cooling. The other end of the scat tube attaches to the aft left lateral engine baffle. Univair will be happy to sell you the aluminum box and probably the fitting for the baffle.

Use a fly cutter to make the hole in the baffle, rivet a fitting for the scat tube on the back side, and you're in business. It may look like a Rube Goldberg arrangement, but it works. We have never had a high oil temperature issue with the airplane. The one complication the box adds is that it's a challenge to run the safety wire from the oil screen though the box and across the accessory case to the acorn nut on the oil pressure relief valve. You will run through your whole vocabulary of cuss words twice the first couple times you do this.

[Jerry Burr]

The blast tube was more to make the fed happy than anything else. It doesn't change the oil temp at the inlet. I posted test results years ago. Maybe someone can find them. The oil temp at the oil filter / oil cooler bypass stays the same with or without the blast tube. Makes a big difference on the gauge however. Jerry

[Steve G]

Check your Mag timing.

[dirthog4]

A cowled small continental engine shouldn't run hot in average temperatures unless there's some other reason.Does temperature rise slow or fast?

[mvivion]

A cowled small continental engine shouldn't run hot in average temperatures unless there's some other reason.Does temperature rise slow or fast?

There is likely nothing wrong with that engine. This is standard on C-90s in PA-11s, at least. As Jerry noted, the blast tube doesn’t do anything to actual oil temps. But the sensor is located at the worst place in the system. The last tube cools the sensor, so oil temperature readings stay within limits.

The oil is not that hot, actually. I suppose if you could relocate the sensor…..

But install the blast tube, and go fly.

MTV

[acroeric]

I had the same issue with my PA-11 with a C-90-8. Instead of putting a blast tube on the oil screen housing to trick the gauge, I took a 2" piece of scat line and routed it to the oil tank as a blast tube. The inlet for it was one of the little outlets just beneath the propeller. It lowered my oil temp at least 20 degrees F. In the winter I take it off so I can get my oil temp to 180 and dump the moisture.

I did check the oil temp with an infered thermometer to verify my oil temp gauge was reading correctly. I could tell it was pretty hot as my idle oil pressure was down to 10 psi at 220 degree oil temp.

A C-90 in a PA-11 will run warmer oil temps if you do not do this. Keep in mind a C-90-8 it is just a 4 quart sump and the accessory housing and oil pump is identical to an A-65 so you will run a lower oil pressure than if you have a C-90-12.

[BC12D-4-85]

Some flying C-90's use Cessna's C-140 under crankcase and oil sump baffling. It can be adapted to other aircraft. It takes cold inlet air from the nose bowl, directs it under the crankcase then down the front of the sump. Look for Cessna's parts diagrams or contact https://www.airforms.biz/index.php?r...product_id=622. I have that setup on my Taylorcraft as the engine came from a C-140.

Gary

[darenlhr]

I do have a blast tube on the bulb the plane was restored in 2010 new everything

[darenlhr]

My idle pressure also gets low when it’s hot

[skywagon8a]

I have a 90 on my pa11 with oil temp issues has anyone installed a oil cooler?

What do you mean by oil temp issues ?
The maximum limit is 225 F.
https://drs.faa.gov/browse/TCDSMODEL...dalOpened=true
Is this something which just recently appeared?
Oil pressure normally is lower at idle when the temperature is warm. The pressure limits are: 30-60 psi. Are you within limits?

If this is something which just recently happened, have you pulled the oil screen to look for anything which shouldn't be there?