Fluid Dynamics & Hose Fittings

Geico266 · #1 10-06-2010, 06:55 PM

I'm plumbing in an oil thermostat into my -12 for the upcoming winter. It will hold the temp at 205F before diverting the oil into the oil cooler.

There is limited space under the cowel so the routing of the hoses is problematic at best. One possible solution would be to use a 180 degree #8 AN racing fitting. This would avoid a good chuck of hose, but the fitting is an aluminum AN fitting used is racing applications.

http://www.aeroquip.cc/fcm1563-fbm1563.aspx

The question is Rotax is not excited about tight 90 degree turns, but "sweeping turns" is acceptable. I assume that is due to the tight turn and the fluid hitting the "back side " of the fitting causing friction.

How would the 180 degree fitting perform? Any problems? The guys who sell them say the friction loss is comparable to a 45 degree AN fitting. Anyone have any data or comments on this fitting on the "hot oil" side of the thermostat. The hot oil should flow easier than the cold oil.

eric_marsh · #2 10-06-2010, 09:28 PM

In my book that fitting constitutes a sweeping turn. I wouldn't be concerned about it as a restriction.

Geico266 · #3 10-06-2010, 10:46 PM

Thanks, I agree, but I have a few more calls to make to convince myself it is okay to try.

Anyone else see any problems or have any flow concerns?

DanH · #4 10-07-2010, 04:17 AM

Larry,
I see no flow issue with a 180 tube hose end, but choosing the aluminum version is risky. Use a steel fitting.

TS Flightlines · #5 10-07-2010, 05:33 AM

a 180* steel fitting. What hose are you using?
Tom

h&jeuropa · #6 10-07-2010, 06:12 AM

Larry,

Some of us Europa folks are using a oil to water heat exchanger instead of an oil thermostat. Advantage is that the oil temp comes up quickly and in the Europa eliminating the oil cooler solves high coolant temp problems. Here's the web site http://www.batinc.net/mocal.htm
The smallest one is being used.

Jim Butcher

Europa XS

Geico266 · #7 10-07-2010, 06:55 AM

Quote:

Originally Posted by TS Flightlines

a 180* steel fitting. What hose are you using?
Tom

I was planning on using Aeroquip FC332 with a fire sleeve.

Geico266 · #8 10-07-2010, 07:00 AM

Quote:

Originally Posted by DanH

Larry,
I see no flow issue with a 180 tube hose end, but choosing the aluminum version is risky. Use a steel fitting.

Dan, I was wondering about that, but they make them and call them AN fittings. There are several aluminum AN fittings used on the -12 though out the fuel system. Is there a standard for firewall forward?

There are so many kinds available. Any help or advice greatly appreciated.

rocketbob · #9 10-07-2010, 07:25 AM

Larry, I am not a fan of the push-on Aeroquip fittings. A Rocket was totalled two years ago because of one of these fittings popping off the hose. A sweeping 180 made out of aluminum is fine, but I would consider a stainless nipple to AN fitting where it attaches to the engine.

Geico266 · #10 10-07-2010, 04:58 PM

Quote:

Originally Posted by rocketbob

Larry, I am not a fan of the push-on Aeroquip fittings. A Rocket was totalled two years ago because of one of these fittings popping off the hose. A sweeping 180 made out of aluminum is fine, but I would consider a stainless nipple to AN fitting where it attaches to the engine.

I've been converted!

The Aeroquip system is okay, but with clamps!