Where is the best location to put the temperature sensor for a TM1000? I had it on the front side of the cylinder head on about the 4th ring down from the top and was getting temps around 180-220F. Someone said I needed to move it to the backside on the 2nd ring down from the top of the cylinder head. Now I'm getting run temps around 325F and the alarm I had set is beeping when I run. My first question is: Is this the best place to put the sensor? And what temps should you see on a dle55RA under normal conditions? I haven't really been able to find a solid answer on that.

I think having the temp senor that close to the muffler is skewing the temperature readings and giving me a much higher temp than what the actual cylinder head is running at. But I want to make sure I'm keeping the cylinder head within the safe operating range. Any ideas???

Thanks!!

You may be getting the ambient muffler temp mixed in there. Your front head temps sounded good. How big is your exit on the bottom of your cowl and do you have a lavour lip on the leading edge of the cutout to allow a low pressure vacuum effect on the hot air?

if you want to know how hot your engine is getting, you need to put the sensor in the top most area, so move it one more "slot" up closet to the spark plug, and the sensor needs to be in the back of the cylinder, so that it is in the "shadow" of the prop wash. this will give you a reading of the "hottest" area of the engine. if you put the sensor in the front, the temp will be 50 to 100 degrees less than what it really is. also, this sensor has to be in direct contact with the metal to give you a good reading.

i have placed the sensors in different parts of the engine, and have noticed drastic differences in temperature. for example, the muffler temp is lower than the temp at that high spot on the back of the cylinder.
also, the crankcase temp will be 150 degrees less than that of the cylinder high spot rear.

i have also placed two sensors at once, one in the front and one in the back of the cylinder, confirming that the prop wash cools the front of the cylinder relative to the back, well, it only makes sense, the air is hitting the front of the cylinder and not the back of it.

i would go with putting it in the back, and then fly it and get your measurements.
fly level for 5 minutes and then for last 5 minutes do hovering, knife edge, uplines, etc... and see what happens to your temperatures with different flight maneuvers. if with doing all these things, there is no change in performance, what ever temps you had, and the temp max may have been, then use that highest temp as your goal to keep it under. set an alarm for any arbitrary temp above your temp max.

interestingly, after you have done this, if not already done, try to maximize your cooling:
two way:
1. baffles in the front
2. an air dam in the bottom of the cowl, just in front of the opening. this "dam" will create a negative pressure directly behind it, and will draw the hot air out of your cowl.
then re do your flight and see if the temperatures have changed with doing this.

+1 orthobird,


I was out running karts this last weekend (I have a water cooled shifter) most of the guys running two stroke AIR cooled wanted to keep their engines below 475*F, yep you heard that right, they also run 16:1 castor based oils. Smells just like a glow engine, but blenzall smells the best of all castor based oils.
Oh, and EGT around 1300.