Hi all,

I have a Lancair 320 (IO-320) which I am just starting to fly "for real" following 18 months of paint / renovations / panel upgrades since purchase.

During climb / cruise / descent all temps are as expected; however in slow flight oil temps rise rapidly even at moderate power settings.  Never saw anything like this in my previous plane, a Lancair 235.  In the pattern on a "nice" day, if the downwind is extended significantly while gear is down oil temps approach the red by the time I land.

Air supply for the oil cooler comes from the aft left side of the aft engine baffle (3" hose around an oval exit), with an additional air feed (1 1/2" hose) coming from a small NACA duct on the left side of the cowl.  Oil cooler is mounted low on the left side of the firewall; air exits down into the low pressure area just above the air exit space by the exhaust pipe.

Is this a common problem on the 320?  Is there a good fix?

Thanks,

Bill Reister
N351E