Cowling Vents

[richlanning]

The Waiex I bought has screened vents in the cowling on the top to let heat out over the turbo and TBI. I know the first time I flew the aircraft the gas cap was so hot I couldn't touch it.

My question is whether these screened openings are actually detrimental to the proper cooling of the turbo and TBI while in flight? Any possible negative aspects to these openings?

My mechanic installed two small scoops over these screened openings in an attempt to get more airflow down and over the turbo and TBI. He installed a funnel under each screen and a short section of hose that directs scooped air directly onto these devices. Thoughts on this? This aircraft is so streamlined I fear this may have significant drag implications. I am getting mixed answers as to the efficacy of this arrangement for cooling.

To further enhance cooling, at least theoretically, the bottom cowl tabs were extended about an inch to try and produce more suction through the engine. Again, is this a feasible approach? Is it worth the drag penalty?

I need folks smarter than me and more familiar with this aircraft to make sure I don't do anything stupid. Appreciate your feedback.

[Bryan Cotton]

There are service bulletins on the Aeroconversions site for the turbo. Before you go inventing a solution, I'd recommend checking for compliance. Welcome to the forum!

http://www.aeroconversions.com/support/aerovee_sb.html

[NWade]

Rich - Please look up the Turbo service bulletins and notices on the AeroConversions or Sonex websites. There have been several versions/revisions and you want to make sure you have the latest one set up.

Also, note that the screened opening in the top of the cowl is not for air *intake*, but rather to allow hot air to vent out of the aircraft when it’s parked after flying. (The main problem with the turbo reliability was traced to heat-soak after shutdown coking the oil left in the turbo. The cowling vent and added liquid cooling system alleviates this)

—Noel

[richlanning]

Thanks. Looks like I have a lot of work ahead of me. Thanks for pointing me to the bulletins.