[Hack]

I've posted once before re: my hot running engine (RV-4, James Plennum,0-320 150hp/CS prop). I have been running oil temps up to 240 deg within 15 minutes of takeoff in ambients of 70 deg up until this weekend. Obviously I was headed back to home plate when the temp got close to 230, but i have no doubt they would have redlined had I not put her down.

Today I changed my oil filter (classic with screen) for a spin on and vernitherm. That has made matters much better, but todays first test flight (85 deg ambient 4850' field elevation) saw oil temps stabilize still high at 220 deg at 1000'AGL(2450 rpm, 22 in manifold, EGT's approx 1400 and hottest cylinder #3 at 400 deg). Stayed there for about 30 minutes but then when I pulled the power, flattened pitch, and went full rich for landing the temp spiked to 240 deg almost immediately and EGT (not CHT's) also spiked to
1600.

I have magnahelix installed right now as well, and at cruise I saw 4.2 in.
The plennum is tight.

So the whole thing is confusing to me. I would like to get your inputs. The biigest question I have now is why the EGT's would spike with power off, but I am still in need ov cooling. Ideas??? Electronics International Instrumentation.

 

[apkp777]

Couple of questions.

1. How many hours on the engine? Is this a new installation?

2. What's your oil pressure during this high temp?

 

[Hack]

106 hours on kit built engine. Press is about 55 at 220 deg oil temp. 75 lb. at 180 deg oil temp.

 

[AltonD]

Just a data point: I read on here where the oil cooler lines wer reversed. The bottom should be the inlet, the top should be the outlet. He reversed and dropped quite a few degree.

http://www.vansairforce.com/community/showthread.php?t=45027

BTW, would check the cal of the oil temp sending unit. Or, just replace it. Check your wiring for high resistance connections. Look at the easy stuff to fix first.