Air temperature of the oil cooler duct

[lockeed]

I plan on installing an air regulator valve in my RV-6. The best and most practical one I found is made of ABS plastic. It's a 3" valve with a push pull cable kit already built in.

The question I have is: how hot can the air be in the air duct leading to the oil cooler? It's a O-360 180hp. Keep in mind that this kit will be used in winter only and Quebec winters are pretty cold.

ABS plastic has a melting point of +/- 221 °F and a standard operating temperature of -4 to 176 °F.

Let me know what you guys think.

 

[N801BH]

I plan on installing an air regulator valve in my RV-6. The best and most practical one I found is made of ABS plastic. It's a 3" valve with a push pull cable kit already built in.

The question I have is: how hot can the air be in the air duct leading to the oil cooler? It's a O-360 180hp. Keep in mind that this kit will be used in winter only and Quebec winters are pretty cold.

ABS plastic has a melting point of +/- 221 °F and a standard operating temperature of -4 to 176 °F.

Let me know what you guys think.

Air temp leading to the oil cooler will be ambient plus just a few degrees if the location of the air source for the cooler is usually in the high pressure area above the cylinders on the rear shroud.. if yours is the one right at the intake of the cooling air in one of the nostrils then the air will be even cooler. Probably ambient +1-2 degrees... You big issue will be heat soak on the plastic part when you park the plane. IMHO.
Ben.

 

[lockeed]

Yes, my air inlet is mounted on the rear shroud over the cylinders. I plan on instaling the valve on the other side of the shroud. Between the shroud and the firewall.

I don't know how hot it can be there when you park the plane after a flight... we'll see... I guess. I might leave the small oil panel in the top cowling open for 10-15 minutes while I park the plane so most of the heat can get out...

 

[Capt. Geoffrey Thorpe]

Got a fiberglass cowl? What temperature is that good for?

 

[lockeed]

Got a fiberglass cowl? What temperature is that good for?

Is it a question?

Mine is aluminum. If you're talkiing about yours, I can't tell. But fiberglass have been used in high temperature environments before. Car body, engine bay, hood etc... Think Corvette... but how much heat it can endure before failing, I don't know.

 

[Henning]

I plan on installing an air regulator valve in my RV-6. The best and most practical one I found is made of ABS plastic. It's a 3" valve with a push pull cable kit already built in.

The question I have is: how hot can the air be in the air duct leading to the oil cooler? It's a O-360 180hp. Keep in mind that this kit will be used in winter only and Quebec winters are pretty cold.

ABS plastic has a melting point of +/- 221 °F and a standard operating temperature of -4 to 176 °F.

Let me know what you guys think.

If you mount that inside the firewall, no problem.

 

[Capt. Geoffrey Thorpe]

Is it a question?

Yes.

Mine is aluminum. If you're talkiing about yours, I can't tell. But fiberglass have been used in high temperature environments before. Car body, engine bay, hood etc... Think Corvette... but how much heat it can endure before failing, I don't know.

In general, since fiberglass cowls typically don't fail when wrapped around the typical aircraft engine, your valve shouldn't either. The maximum temperatures are in the same ballpark (though there are some high temperature thermoset plastics, that's not what we are talking about here.)

Yes, I do have a fiberglass cowl. They are pretty common.

 

[Dan Thomas]

Yes.



In general, since fiberglass cowls typically don't fail when wrapped around the typical aircraft engine, your valve shouldn't either. The maximum temperatures are in the same ballpark (though there are some high temperature thermoset plastics, that's not what we are talking about here.)

Yes, I do have a fiberglass cowl. They are pretty common.

Fiberglass will take a lot more heat than ABS. Fiberglass uses either polyester or vinyester resin, thermosetting compounds that cure and thereafter holds their shape. ABS is a thermoplastic that gets soft (or melts) when temps rise.

The valve should be located in the duct closer to the oil cooler. Down lower it won't get baked so much after shutdown.

Dan

 

[Capt. Geoffrey Thorpe]

Fiberglass will take a lot more heat than ABS. Fiberglass uses either polyester or vinyester resin, thermosetting compounds that cure and thereafter holds their shape. ABS is a thermoplastic that gets soft (or melts) when temps rise.

The valve should be located in the duct closer to the oil cooler. Down lower it won't get baked so much after shutdown.

Dan

I believe that if you actually look at the specs for resins commanly used for homebuit aircraft you will find glass transition temperatures not far from the temperature quoted by the O.P.

E-Z POXY, for example is listed as having a glass transition temperature of about 150F. http://www.aircraftspruce.com/catalog/cmpages/ezpoxy.php

Aircraft Spruce carries a vinyl ester resin which does a bit better - 210 F
http://www.aircraftspruce.com/catalog/cmpages/vinylester.php Better, but not by that much.