My O-320 used to run pretty consistent 190* oil temps, even in 90* ambient weather, with an occassional peak at 200 in a climb. Over the winter, I was lucky to get to 170. During my spring flights, the O/T seemed to track as normal, maybe closer to 200. A few flights ago, I noticed continued oil temps around 200. Second to last flight, they peaked around 215 and the last flight topped out at 225. Clearly a trend that needs to be resolved. It is possible that this has been building all winter, as I would not have known. Pretty hard to get excessive oil temps when the ambient temp is 30*
A couple of flights ago I replaced the oil cooler lines with better quality hose and fittings when I re-did all of fuel lines for the FI installation. I confirmed solid flow through the hoses before installation.
My current thinking is that my problems lies in either the Vernatherm or a partially blocked cooler.
I have been finding small black carbon chunks in my oil filter. Not sure if they are continually being made or remnants from the major carbon problem I had due to the glazed cylinder 70 hours ago. I was thinking that the oil cooler gets oil before the filter and it could be partially blocked from carbon. However, the rapid onset doesn't really support that theory. I suppose that draining cooler to replace the hoses could have upset something to cause the rapid onset of symptoms.
I pulled the Vernatherm. I put it in 200* water and it expands .180". The specs say that a minimum of .160" is a passing grade. I am wondering if expanding further then this increases the cracking pressure of the spring and therefore keeping more oil flowing through the cooler.
Has anyone done this test and kept the measurements of the expanded vernatherm? I hate to spend $270 for another if mine is working properly.
Does anyone have any thoughts or experience that could help here? Any other possible causes that I may have missed. I can't see how this could be airflow related, as it came on over night and I have noticed no increases in CHT's or done anything to change flow. My cooler is a 9 row mounted on the baffling behind #4.
Thanks for your assistance here.
Larry
A couple of flights ago I replaced the oil cooler lines with better quality hose and fittings when I re-did all of fuel lines for the FI installation. I confirmed solid flow through the hoses before installation.
My current thinking is that my problems lies in either the Vernatherm or a partially blocked cooler.
I have been finding small black carbon chunks in my oil filter. Not sure if they are continually being made or remnants from the major carbon problem I had due to the glazed cylinder 70 hours ago. I was thinking that the oil cooler gets oil before the filter and it could be partially blocked from carbon. However, the rapid onset doesn't really support that theory. I suppose that draining cooler to replace the hoses could have upset something to cause the rapid onset of symptoms.
I pulled the Vernatherm. I put it in 200* water and it expands .180". The specs say that a minimum of .160" is a passing grade. I am wondering if expanding further then this increases the cracking pressure of the spring and therefore keeping more oil flowing through the cooler.
Has anyone done this test and kept the measurements of the expanded vernatherm? I hate to spend $270 for another if mine is working properly.
Does anyone have any thoughts or experience that could help here? Any other possible causes that I may have missed. I can't see how this could be airflow related, as it came on over night and I have noticed no increases in CHT's or done anything to change flow. My cooler is a 9 row mounted on the baffling behind #4.
Thanks for your assistance here.
Larry
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