OS .18 CVR
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OS .18 CVR
Great engine...I currently have it installed in my Duratrax Evader ST. less than a gallon through it..I followed the instructions for break in and I am fairly happy with the performance....the issue I have is that during coooler weather it seems to pop or pulse after a throttle blip or run....I am wondering if the cooler temps here in Canada during the winter months is causing the popping or pulsing...it sounds like motorcross bike almost..
can I tune for colder weather if so where to start..
any suggestions appreciated
thanks
Ron
can I tune for colder weather if so where to start..
any suggestions appreciated
thanks
Ron
#2
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RE: OS .18 CVR
As the weather and the seasons change, you will have to readjust the needles of any glow engine. Even during the same day, if the weather changes a lot. We've seen dramatic changes in needle settings from one day to the next, or even from a cool morning to a hot afternoon.
If you haven't changed any needle settings, then that's why the engine's handling has changed. You need to check the needle settings at the start of each day's running to get them right.
Also, for cooler weather, you may need to go to a fuel with a little more nitromethane to help keep the engine warmer. If it's over-cooling, you may need to use a hotter fuel, or restrict the airflow through the engine...just as they do on full-size trucks in winter...they block-off part of the radiator to keep the engine from over-cooling.
If you haven't changed any needle settings, then that's why the engine's handling has changed. You need to check the needle settings at the start of each day's running to get them right.
Also, for cooler weather, you may need to go to a fuel with a little more nitromethane to help keep the engine warmer. If it's over-cooling, you may need to use a hotter fuel, or restrict the airflow through the engine...just as they do on full-size trucks in winter...they block-off part of the radiator to keep the engine from over-cooling.
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RE: OS .18 CVR
that sounds kewl.....get it...LOL...thanks for the help..I usually tune with the first tank and go from there....in the warm weather I have not had to touch the needle adjustment at all but now it is getting cooler I have had to tune it every time I run it......last night was about 5 deg.C and I leaned it out a bit and it was screaming ran just as good as in the warmer weather.....I am very happy with this engine.....puts out alot of power...
thanks again
thanks again
#5
My Feedback: (11)
RE: OS .18 CVR
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.
We've found that reliance on engine temps for setting the carb is a sure way to shorten the life of your engine.
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.
We've found that reliance on engine temps for setting the carb is a sure way to shorten the life of your engine.
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RE: OS .18 CVR
Thanks for the good advice! I will start logging temperatures versus rpm on a specific set-up and start squeezing down the water cooling.
Is there an absolute maximum temperature that you do not want to exceed however (either Head temperature or EGT)?
Is there an absolute maximum temperature that you do not want to exceed however (either Head temperature or EGT)?
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RE: OS .18 CVR
I have yet to put a temp gun to any of my engines....I use 3 things to tune my engines....sound...performance...and a good smoke trail...lean it by 1/8th turns and when you notice a performance drop....go back 1/8 turn...that is the way I have tuned both needles...
2.5 TRX-----5 gallons still has compression
OS 18 2 gallons and it it really just broken in nicely...
2.5 TRX-----5 gallons still has compression
OS 18 2 gallons and it it really just broken in nicely...