High exhaust temp is usually caused by retarded ignition timing. I would recommend resetting it to the base Lycoming value.
Running advanced won't help either during the initial trial period.
If you have decent air flow thru the cowl and oil cooler, you should have lower oil temps. My T-18 with O-290 barely gets over 150 in the summer unless I have an airflow restrictor in front of the cooler.
I wonder what the EGT redline value is? Are you reading a temp, or is it some unmarked value?
Also, at what phase of operation do you notice it?
Do you have EGT probes on all 4 cylinders or only one? How does the engine run, ignore the gauges, does it run powerfully and smoothly?
Leaned out 1450 degrees is fine. Rich could be 1300 degrees at full or high cruise power.
Do a google search for the Lycoming operating manual, it's not hard to find (for free) on line. it's very helpful.
The previous suggestion that the engine should speed up before dying when shut down with idle mixture cut off is correct.
Did you check the fuel strainer in the admission fitting on the carb. It's a little screen filter. If dirty and it cannot allow enough flow for full power, the engine would run lean after the fuel in the carb bowl got low. This would allow full take off power for several seconds prior to going lean.
Does the fuel line get hot in flight?
EGT circuits can be bedeviled by many application errors and a review of them at Electronic International, in the Downloads section will be a big help
www.buy-ei.com "The pilot's manual for Learning and Diagnosing Engine Problems"
Good luck! My O-290 runs great!
I used it, in my T-18 to get up to speed for my first flights in the RV-8 13BT.
-----Original Message-----
From: DLOMHEIM <DLOMHEIM@aol.com>
To: Rotary motors in aircraft <flyrotary@lancaironline.net>
Sent: Wed, Mar 19, 2014 4:12 am
Subject: [FlyRotary] Off Topic Lycoming Question...
Tracy:
This engine has 155 hrs on it and the cylinders were pulled and sent in for
inspection and they checked out good and were simply honed and new rings
added. The oil temp has been running right at 220 degrees (taken at the
oil screen on the accessory case as is std on the O-290s). I have read
that should drop a bit once the rings fully seat in. Next time a run it
I'm also going to shoot the front two cylinders with my infra red
thermometer right after shut down to see what it shows on the barrels, and I
also am going to move the sender to a lower plug and see if that changes
anything.
EGTs are my real puzzle though as to why all four would be maxed
out. I've never heard of a Lycoming generating that hi an EGT and
that was the sole domain of rotaries! :)
Thanks for your ideas on this...
Doug