Temperature value for a heli 55HZ-H
11-18-2009, 11:29 AM
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Temperature value for a heli 55HZ-H
Hi Bill,
I would like to know what will be a high temperature value for an OS 55HZ-H using a thermistor placed between the 3 and 4th fin from the top of the head and within 0.5 mm from the exterior wall on the opposite side from the carburetor and is secured with Arctic Alumina Thermal Adhesive. I have run a 50SX-H with the highest temperature value set at 250 degrees Fahrenheit and there were not any bearings, piston or ring failures running on Cool Power 30% fuel.
I understand that a temperature value depends on many factors (ambient conditions, load, fuel, pipe, cooling, temperature probe, location etc.) and I am just looking for your opinion on what could be a high temperature value for running this engine. I have heard from other modelers numbers from 194 to 290 (90 to 143 degrees Celsius) for a 50SX-H engine.
BTW I am using Multigov Pro for mixer control.
Thanks in advance for your support.
I would like to know what will be a high temperature value for an OS 55HZ-H using a thermistor placed between the 3 and 4th fin from the top of the head and within 0.5 mm from the exterior wall on the opposite side from the carburetor and is secured with Arctic Alumina Thermal Adhesive. I have run a 50SX-H with the highest temperature value set at 250 degrees Fahrenheit and there were not any bearings, piston or ring failures running on Cool Power 30% fuel.
I understand that a temperature value depends on many factors (ambient conditions, load, fuel, pipe, cooling, temperature probe, location etc.) and I am just looking for your opinion on what could be a high temperature value for running this engine. I have heard from other modelers numbers from 194 to 290 (90 to 143 degrees Celsius) for a 50SX-H engine.
BTW I am using Multigov Pro for mixer control.
Thanks in advance for your support.
11-19-2009, 09:50 AM
#2
My Feedback: (11)
RE: Temperature value for a heli 55HZ-H
O.S. has no recommendations for operating temperatures, and we do not use them at all.
It's not possible for us to give you an actual temperature or temperature range for your engine. The specific temperature is determined by too many factors. There is only one way to determine at what temperature your engine should be run. You have to run it first and then find out what temperature the engine reaches.
Make sure your engine is operating properly with the performance you expect. Use the exact setup every time...fuel, exhaust system, plug, measurement location, and so forth. If you change anything, the temperature will change. Once you have the engine running the way you want it. Take your measurement. This is your starting point. You will have to take measurements over time to find out how the weather affects it. As the air temperature and humidity change from day-to-day, the operating temperature will change. Eventually, you'll find a temperature range that you can work with.
Engine temperature is not an absolute number for setting your engine. It is only a guide, and can help alert you to potential problems. The only sure way to make sure your engine is running correctly is to see how it's running. An engine can be operating at "correct" temperatures, but not running well.
Finally, use any temperatures you read about, or people tell you, as rough information. The only useful numbers are the ones you actually measure when your engine is running correctly. If your engine is running correctly, then what you measure is correct, even if some else says it's too high or too low. Don't worry about the differences. Each engine is in a unique installation with a unique set of circumstances, so there can be wide variances in engine temperature.
It's not possible for us to give you an actual temperature or temperature range for your engine. The specific temperature is determined by too many factors. There is only one way to determine at what temperature your engine should be run. You have to run it first and then find out what temperature the engine reaches.
Make sure your engine is operating properly with the performance you expect. Use the exact setup every time...fuel, exhaust system, plug, measurement location, and so forth. If you change anything, the temperature will change. Once you have the engine running the way you want it. Take your measurement. This is your starting point. You will have to take measurements over time to find out how the weather affects it. As the air temperature and humidity change from day-to-day, the operating temperature will change. Eventually, you'll find a temperature range that you can work with.
Engine temperature is not an absolute number for setting your engine. It is only a guide, and can help alert you to potential problems. The only sure way to make sure your engine is running correctly is to see how it's running. An engine can be operating at "correct" temperatures, but not running well.
Finally, use any temperatures you read about, or people tell you, as rough information. The only useful numbers are the ones you actually measure when your engine is running correctly. If your engine is running correctly, then what you measure is correct, even if some else says it's too high or too low. Don't worry about the differences. Each engine is in a unique installation with a unique set of circumstances, so there can be wide variances in engine temperature.
11-19-2009, 07:20 PM
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RE: Temperature value for a heli 55HZ-H
Bill,
I absolutely agree with you on the “each engine is in a unique installation”. One time I have 2 of everything the same models (heli, blades, engine, pipe, electronics and fuel) and the tuning was very different. I checked again and again for air leaks, clogged lines, glow plugs etc. but I could not find what the difference is. After a while I gave up and I just fly them! Both run great just different needle and temperature settings.
This is kind of a personal quest of finding out why RC Nitro engines(I have not work with gasoline nor turbine engines yet) are so “peculiar” when it comes to tuning. I have worked with 2-stroke motorcycle engines (the old days with carburetors and tuned pipes) and the tuning was quite reputable for the same setup.
Anyway, thank you for the extended information and verifying this peculiarity with RC engines. I guess this is half the fun of a miniature internal combustion engine.
Nick
I absolutely agree with you on the “each engine is in a unique installation”. One time I have 2 of everything the same models (heli, blades, engine, pipe, electronics and fuel) and the tuning was very different. I checked again and again for air leaks, clogged lines, glow plugs etc. but I could not find what the difference is. After a while I gave up and I just fly them! Both run great just different needle and temperature settings.
This is kind of a personal quest of finding out why RC Nitro engines(I have not work with gasoline nor turbine engines yet) are so “peculiar” when it comes to tuning. I have worked with 2-stroke motorcycle engines (the old days with carburetors and tuned pipes) and the tuning was quite reputable for the same setup.
Anyway, thank you for the extended information and verifying this peculiarity with RC engines. I guess this is half the fun of a miniature internal combustion engine.
Nick
11-20-2009, 10:04 AM
#4
My Feedback: (11)
RE: Temperature value for a heli 55HZ-H
Tuning will vary because glow engines use methanol-based fuel. Methanol has an 8:1 fuel/air ratio when it's burning. That means that a small change in the amount of air will make quite a change in the fuel needed...so you need to change the needle setting anytime the air density changes...warm day to cool day or reverse, more humidity vs. less humidity, higher vs. lower altitudes, and so on. Small differences in the manufacture of the components can also make quite the difference.
