Hi Al,
I don't see an issue with those temps, and you cruise temps in particular are right on. It is interesting that you have such a big difference between climb and cruise. In my plane the difference the difference is less marked.
You may find that OAT is going to play a bigger role than you think. Also, heat soaked engines really make a huge difference for that initial climb out. Even the difference between starting with a plane that had been parked in the hangar vs. sitting at the tiedown in the sun made a very noticeable difference in climbout temps.
Your situation in particular sounds like a spray bar may be just the ticket. While I was somewhat limited in power usage in all phases of flight, your problem seems to be just climb-out. This means you only need to carry enough water for the climbout portion of flight. Relatively simple to install. Have fun flying your plane for a while before you have to drudge on with a major cooling system change - - because there will always be something you want to change... you have to fight the temptation every now and then and just fly! I recommend you fly off your time, install a spray bar, come give me the flight you promised and just fly around for a year or so. Then you will have a whole list of things you want to change and you can do them all at once.
On 6/9/07, Al Gietzen <ALVentures@cox.net> wrote:
I guess we've had this discussion before but to me it still seems like a grey area.
The limit has to do with temperature, time, and limiting component.
At typical cruise conditions I have coolant temps of 160-170F and oil temps about 20 degrees higher. Short term climb out (1000 – 2000') I see oil getting up 215 -220 and coolant around 200. If I continue climb, I need to reduce power to keep them at those levels; which means climb rates of 500-700 FPM with OAT of 65F, and maybe a bit less if OAT is higher. I don't like being limited to that climb rate when I have power for considerably more; but the real question is: Is that temp level an issue if sustained for 10-15 minutes? And what is it affecting?
I expect to make some modification to improve airflow through the cooler, just deciding if it is urgent or if it can wait for another 10 -20 hrs of flying. Anytime I go east from my airport I have to climb from 1400' to about 7000' to clear high terrain.
Thanks,
Al
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