hecilopter
Well Known Member
Just trying to get a handle on what is different, as we are having oil temp problems on a new RV-7A. After reading tons of posts, I think it is coming down to engine configuration to explain high oil temp. We have tried the SW 8406R oil cooler ($500+) and it may have lowered temps 10-15 degrees over the Aero Classic from Van's. Before we start cutting the cowling for exit air or adding louvres, I would like some input to try and find a clue as to what configurations seem to run hot.
Here is our scenario: 2 identically cowled and baffled RV-7A's. Both have oil coolers mounted on the baffle behind cylinder #4. The top cowl inlet ramps sealed on both. Both have the vertical draft intake with the cowl scoop. We have verified no blockage in the oil cooler hoses, and the oil temp probe reads within 1 degree of a thermometer when both dipped in boiling water. When flying together side by side the other day Plane 1 was showing oil temps at 155, Plane 2 was showing temps at 230. We ran for 10 minutes side by side, OAT about 75 degrees.
Plane 1 - Superior XP-360, carb, Slick mags, 8.5:1 pistons, Hartzell BA prop. Has run cool (< 180 degrees) since first start, sometimes too cool, now has 310 hrs. All fairings and wheelpants, but did NOT have them during break-in. Aero Classics oil cooler from Van's FWF kit.
Plane 2 - ECI IO-360, Precision Silverhawk FI, Dual P-mag, 9:1 pistons, Hartzell BA prop, cam oil squirters. Ran at 235 degrees with Aero Classic cooler, runs about 220 degrees with SW 8406R cooler. Has about 7 hrs now. CHT's in the 340-360 range on all. No wheelpants. Running at 24"/2400 RPM for break-in.
What I want to know is, does the electronic ignition and/or 9:1 pistons and cam oilers or piston oilers have anything to do with it. Plane 1 has none of these.
Does anyone out there have an -A model, or either model for that matter that has a baffle mounted cooler, 9:1 pistons or higher, electronic ignition, and cam or piston oilers that has never run hot?
Another way to say it, does anyone out there have a baffle mounted cooler, 8:5:1 or less pistons, mags and NO cam or piston oilers that has had cooling problems?
Just trying to get to the bottom of this and would appreciate input from anyone with either of the above configurations to see if it is an engine configuration problem causing the high temps.
Thanks in advance!
Here is our scenario: 2 identically cowled and baffled RV-7A's. Both have oil coolers mounted on the baffle behind cylinder #4. The top cowl inlet ramps sealed on both. Both have the vertical draft intake with the cowl scoop. We have verified no blockage in the oil cooler hoses, and the oil temp probe reads within 1 degree of a thermometer when both dipped in boiling water. When flying together side by side the other day Plane 1 was showing oil temps at 155, Plane 2 was showing temps at 230. We ran for 10 minutes side by side, OAT about 75 degrees.
Plane 1 - Superior XP-360, carb, Slick mags, 8.5:1 pistons, Hartzell BA prop. Has run cool (< 180 degrees) since first start, sometimes too cool, now has 310 hrs. All fairings and wheelpants, but did NOT have them during break-in. Aero Classics oil cooler from Van's FWF kit.
Plane 2 - ECI IO-360, Precision Silverhawk FI, Dual P-mag, 9:1 pistons, Hartzell BA prop, cam oil squirters. Ran at 235 degrees with Aero Classic cooler, runs about 220 degrees with SW 8406R cooler. Has about 7 hrs now. CHT's in the 340-360 range on all. No wheelpants. Running at 24"/2400 RPM for break-in.
What I want to know is, does the electronic ignition and/or 9:1 pistons and cam oilers or piston oilers have anything to do with it. Plane 1 has none of these.
Does anyone out there have an -A model, or either model for that matter that has a baffle mounted cooler, 9:1 pistons or higher, electronic ignition, and cam or piston oilers that has never run hot?
Another way to say it, does anyone out there have a baffle mounted cooler, 8:5:1 or less pistons, mags and NO cam or piston oilers that has had cooling problems?
Just trying to get to the bottom of this and would appreciate input from anyone with either of the above configurations to see if it is an engine configuration problem causing the high temps.
Thanks in advance!
Last edited: