Does anyone have a copy of the drawing for the air extraction duct which can be fitted to the lower cowling?  It was written up in a Lancair quarterly publication (Lancair News?) some years ago.  I cannot find my copy and a buddy of mine is having the usual oil cooling problems.

Ian,

 

Do you mean a "submerged shark gill" opening?  Square sided reverse NACA duct? He may need to do some other investigations before cutting a hole in the cowling.

 

I don't understand the "usual" oil cooling problem - there are so many sources of oil cooling failure.

 

1.  Is the engine broken in?  New engines often run hotter as the friction from breaking in the rings contributes to additional heat.

 

2. Is air actually getting to/thru the cooler?  Is it mounted at the air intake or at the rear baffle?  Does it utilize an air duct taken off the baffle and then into a plenum?  Is the air obtained from an effective NACA duct?  Is the cooler mounted at an angle to the cooling air stream?

 

3. Is the air getting away from the cooler?  Is the exit air confounded by some other blast of air or backup of air?

 

4. Are the engine temps relatively normal, but the oil temp is high?  Has the Vernatherm been checked?  Is the cooler an old one and needs cleaning (sludge removal)?  Is it a known good cooler - Stewart-Warner?  Is it big enough for the engine?

 

So many questions, so little time..........