Correct set up of nitro engines:
Who never had anything to do with nitro engines but still wants to fly with one, needs to invest some time. As easy as with an electric engine where just plug everything together and everything works it is not... if you have the possibility to ask an experienced pilot for help, then you should do it, to set up a nitro engine isn#t very hard, but it it is much more easy if you have someone who can help you.
Start:
The starting isn't a big thing and once you get some feeling it is most time very easy. You only have to decide if you want to start by hand or by electric starter:
By hand:
Full throttle
Cover with one finger the suction side of the carb. and spin the prop 3-5 times. (This is done to suck the fuel from the tank to the carb., if the engine run a shortly before, this must maybe not be done. When there is enough fuel in the carb., the sound changes significant)
Close throttle to higher idle
Attach the glowing
Use a screwdriver with a wood handle (chickenstick) or a rubber glove for you finger (!!!!) and spin the prop
After 2-3 tries it should start to come to life or already run at idle speed
After it is running 20-30 seconds, you can remove the glowing
By electric starter:
Throttle to higher idle
Attach glowing
Put the electric starter at the spinner and turn it on
After 2-4 seconds, the engine should run on its own
After it is running 20-30 seconds, you can remove the glowing
The electric starter seems to be very nice, but there are a few disadvantages:
it can also have some advantages to use an electric starter, engines with a small displacemen or carbs. with a flat slider will not be easy to start by hand. So you should only use an electric starter where it makes sense.
By hand:
Full throttle
Cover with one finger the suction side of the carb. and spin the prop 3-5 times. (This is done to suck the fuel from the tank to the carb., if the engine run a shortly before, this must maybe not be done. When there is enough fuel in the carb., the sound changes significant)
Close throttle to higher idle
Attach the glowing
Use a screwdriver with a wood handle (chickenstick) or a rubber glove for you finger (!!!!) and spin the prop
After 2-3 tries it should start to come to life or already run at idle speed
After it is running 20-30 seconds, you can remove the glowing
By electric starter:
Throttle to higher idle
Attach glowing
Put the electric starter at the spinner and turn it on
After 2-4 seconds, the engine should run on its own
After it is running 20-30 seconds, you can remove the glowing
The electric starter seems to be very nice, but there are a few disadvantages:
- If there is too much fuel inside the combustion chamber, he can hydraulicaly block and because of that, he can take serious damage. If startet by hand, you would not have the power to turn it over when it blocks
- You also have to carry a 12V power supply with you
it can also have some advantages to use an electric starter, engines with a small displacemen or carbs. with a flat slider will not be easy to start by hand. So you should only use an electric starter where it makes sense.
Correct set up:
I'll reduce to the correct set up of an already broken in engine. How to break in a new engine the best way will stand in the also delivered manual.
At first, the servo reverse must be set up correct (please not while the engine is running):
Put the throttle stick and also the trim full worward, set the travel so that the carb. is fully opened.
Then pull back the throttle stick and also the trim fully, set the travel that the carb is now fully closed.
If the throttle stick is now back and the trim is forward, you have the position when yous tart the engine. With the trim in the middle you have the normal idle position and with the trim back, the engine will stop.
When the engine is running, try to keep him running for 2-3 minutes to get it to working temperature. If this is done, you slowly open the throttle until you reached full throttle. If he isn't running good at that time, it can happen that you need to keep the glowing attached.
Now we turn the main needle in both directions and listen where the engine is rotating higher. On most engines you will go to the lean side while turning the needle clockwise and to the rich side while turning the needle counterclockwise. Now you turn the needle as long, as your each the maximum rpm. Then you turn it slowly (1 click every 5 seconds) to the right until the rpms are going significant down, this happens normaly within one click. When you#ve reached that point, you turn back the needle 2-3 clicks on the left side.
To be sure that the engines gets enough fuel while accelerating, we turn the model now with full speed with the nose traight up in the air and take care if the rpms are changing. Normaly the needle set up is fitting already quite good, but to be on the safe side, you should also tun now the needle as long as you get to the highest rpm and then go one click on the rich side (left).
To be very sure that everything is ok with the fuel support, you can shake the modell a little bit and take care the rpm won't go down. When we put the model back to the horizontal, we need to check that the rpm won't go down very significant.
With that type of set up, you are most time a little bit on the rich side, which means that you won't have the really full power of the engine, but you'll be on the safe side for the lifetime of the engine.
So the engine is set up right for full throttle, now we get to the tricky part, the set up of the idle. This have to be done AFTER the set up of the full throttle because the idle needle is depending on the full throttle needle!
The throttle will now be closed slowley until the stick is alle the way back, the trim should still stay in forward. If the carb. is set up according to the manual of the manufacturer, then the engine will keep running in most cases, but should it stop during going back, you can only guess at first time if it needs to be more rich or more lean. In that case, turn the idle needle 5 clicks or a half rotation in any direction and check if it become better. If not, try the other direction. If it should run a litle bit longer or better when you let the glowing attached, then this can be a sign that it is on the rich side and you need to turn it more lean. A beginner, it is only a trial and error thing, but as experienced pilot, you can msotly say if it is running too rich or too lean, so it is really a big help to have an experienced guy with you. Also on most carbs., the turning direction of the idle needle is the opposite of the full throttle needle, this means that the idle speed gets richer when turning the needle to the right and more lean when turning to the left.
When he is running in idle more or less, still with the trim in front, then you suddenly open the throttle and take care what the enigne is doing. if he spins up very fast and stops suddenly, it is too lean, if it only accelerates very slowly, then it is too rich. Now we set up the idle needle in small steps (1-2 clicks or 1/8 - 1/4 turn) so long to the rich or lean side until the engine accelerates very good. Also here it is more safe to be a little bit on the rich side. To check if the set up is correct, you let him run 1-2 minutes in idle speed. The engine isn't allowed to stop and if you suddenly open the throttle, it must accelerate very good.
When the engine is running ok, we are going to set up the correct idle speed. Therefor we move the trim in the middle position and change the servo travel as long as the engine is running safe at idle. Also here it needs to run 1-2 minutes without stopping. If this thing is set up correct, it can be safely stoppe with moving the trim back.
If this is all done, you get an engine which should run very good and after a few test runs on the ground, there is no reason for not flying with it. Take care that you should immediately climb up ver high, if the engine should stop, it is alway better to have enough air under the wings.
Also take care, that you need to set up the full speed needle every other day about 1-2 clicks. Different atmosphere, temperature and humidity can take effect on the fuel / air mixture.
To the stopping of the engine is still something to say:
If you're flying without nitro, you can always stop the engine with the trim, but if you're flying with nitro, you should stop the engine by pinching the fuel hose or by running out of fuel. With that method, you prevent damage of the bearings by the nitro. Also the tank should be emptied always after a flying day.
If you know that the engine won't be used for months (e.g. over the winter) you should always stop it by letting it run out of fuel. At first, the tank will be emptied, the carb. will be emptied and also there should only stay very little fuel in the engine itself. Also, after the engine is cooled down, it is usefull to preserve the engine with some weapon spray into the open carb and the glow plug opening. This should preserve rust inside during the months it won't be used.
At first, the servo reverse must be set up correct (please not while the engine is running):
Put the throttle stick and also the trim full worward, set the travel so that the carb. is fully opened.
Then pull back the throttle stick and also the trim fully, set the travel that the carb is now fully closed.
If the throttle stick is now back and the trim is forward, you have the position when yous tart the engine. With the trim in the middle you have the normal idle position and with the trim back, the engine will stop.
When the engine is running, try to keep him running for 2-3 minutes to get it to working temperature. If this is done, you slowly open the throttle until you reached full throttle. If he isn't running good at that time, it can happen that you need to keep the glowing attached.
Now we turn the main needle in both directions and listen where the engine is rotating higher. On most engines you will go to the lean side while turning the needle clockwise and to the rich side while turning the needle counterclockwise. Now you turn the needle as long, as your each the maximum rpm. Then you turn it slowly (1 click every 5 seconds) to the right until the rpms are going significant down, this happens normaly within one click. When you#ve reached that point, you turn back the needle 2-3 clicks on the left side.
To be sure that the engines gets enough fuel while accelerating, we turn the model now with full speed with the nose traight up in the air and take care if the rpms are changing. Normaly the needle set up is fitting already quite good, but to be on the safe side, you should also tun now the needle as long as you get to the highest rpm and then go one click on the rich side (left).
To be very sure that everything is ok with the fuel support, you can shake the modell a little bit and take care the rpm won't go down. When we put the model back to the horizontal, we need to check that the rpm won't go down very significant.
With that type of set up, you are most time a little bit on the rich side, which means that you won't have the really full power of the engine, but you'll be on the safe side for the lifetime of the engine.
So the engine is set up right for full throttle, now we get to the tricky part, the set up of the idle. This have to be done AFTER the set up of the full throttle because the idle needle is depending on the full throttle needle!
The throttle will now be closed slowley until the stick is alle the way back, the trim should still stay in forward. If the carb. is set up according to the manual of the manufacturer, then the engine will keep running in most cases, but should it stop during going back, you can only guess at first time if it needs to be more rich or more lean. In that case, turn the idle needle 5 clicks or a half rotation in any direction and check if it become better. If not, try the other direction. If it should run a litle bit longer or better when you let the glowing attached, then this can be a sign that it is on the rich side and you need to turn it more lean. A beginner, it is only a trial and error thing, but as experienced pilot, you can msotly say if it is running too rich or too lean, so it is really a big help to have an experienced guy with you. Also on most carbs., the turning direction of the idle needle is the opposite of the full throttle needle, this means that the idle speed gets richer when turning the needle to the right and more lean when turning to the left.
When he is running in idle more or less, still with the trim in front, then you suddenly open the throttle and take care what the enigne is doing. if he spins up very fast and stops suddenly, it is too lean, if it only accelerates very slowly, then it is too rich. Now we set up the idle needle in small steps (1-2 clicks or 1/8 - 1/4 turn) so long to the rich or lean side until the engine accelerates very good. Also here it is more safe to be a little bit on the rich side. To check if the set up is correct, you let him run 1-2 minutes in idle speed. The engine isn't allowed to stop and if you suddenly open the throttle, it must accelerate very good.
When the engine is running ok, we are going to set up the correct idle speed. Therefor we move the trim in the middle position and change the servo travel as long as the engine is running safe at idle. Also here it needs to run 1-2 minutes without stopping. If this thing is set up correct, it can be safely stoppe with moving the trim back.
If this is all done, you get an engine which should run very good and after a few test runs on the ground, there is no reason for not flying with it. Take care that you should immediately climb up ver high, if the engine should stop, it is alway better to have enough air under the wings.
Also take care, that you need to set up the full speed needle every other day about 1-2 clicks. Different atmosphere, temperature and humidity can take effect on the fuel / air mixture.
To the stopping of the engine is still something to say:
If you're flying without nitro, you can always stop the engine with the trim, but if you're flying with nitro, you should stop the engine by pinching the fuel hose or by running out of fuel. With that method, you prevent damage of the bearings by the nitro. Also the tank should be emptied always after a flying day.
If you know that the engine won't be used for months (e.g. over the winter) you should always stop it by letting it run out of fuel. At first, the tank will be emptied, the carb. will be emptied and also there should only stay very little fuel in the engine itself. Also, after the engine is cooled down, it is usefull to preserve the engine with some weapon spray into the open carb and the glow plug opening. This should preserve rust inside during the months it won't be used.
But it is still not running?
Ok, so you've followed to above given instructions but the engine still won't run?, Then this can have many reasons, but at first I would suggest to ask an experienced pilot. However, I'll sum up some good known reasons which can happen:
The engine was not used for many months or even years:
It won't even start:
Piston ring is resinified and through that there is no compression -> disassembling and cleaning
Carb. is resinified and because of that no fuel is going through -> disassembling and cleaning
Fuel hose damaged or come off -> check, replace
Glow plug defect -> disassembling and check if it is glowing with attached battery, if not, replace
Not running, won't set up correct or any other strange thing:
Carb. is not mounted tight on the engine -> mount it new and tight
Needle resinified -> disassembling and cleaning
Tank is not getting pressure from the exhaust -> check the pressure hose from the exhaust to the tank, check tightness of the tank system
Fuel filter resinified -> disassembling and cleaning or replace
The rngine run perfect shortly before:
It won't even start:
Fuel filled up? -> with an electric fuel pump, the direction was messed up many times...
Glowing charged? -> the glow battery becomes most times then empty, when you need it
Glowing plug defect -> disassembling and check if it is glowing with attached battery, if not, replace
Fuel filter blocked -> disassembling and cleaning or replace
Model selected correct on the transmitter and carb. in start position? -> happens more oftne then you would believe...
It won't run, can't set up or any other strange things:
Carb. become loose -> remount it
Tank isn't getting pressure -> Check the pressure hose from the exhaust to the tank, check the tightness of the fuel system
Fuel filter blocker -> Disassembling and cleaning or replace
Needle de-adjusted -> set it up new
The engine was not used for many months or even years:
It won't even start:
Piston ring is resinified and through that there is no compression -> disassembling and cleaning
Carb. is resinified and because of that no fuel is going through -> disassembling and cleaning
Fuel hose damaged or come off -> check, replace
Glow plug defect -> disassembling and check if it is glowing with attached battery, if not, replace
Not running, won't set up correct or any other strange thing:
Carb. is not mounted tight on the engine -> mount it new and tight
Needle resinified -> disassembling and cleaning
Tank is not getting pressure from the exhaust -> check the pressure hose from the exhaust to the tank, check tightness of the tank system
Fuel filter resinified -> disassembling and cleaning or replace
The rngine run perfect shortly before:
It won't even start:
Fuel filled up? -> with an electric fuel pump, the direction was messed up many times...
Glowing charged? -> the glow battery becomes most times then empty, when you need it
Glowing plug defect -> disassembling and check if it is glowing with attached battery, if not, replace
Fuel filter blocked -> disassembling and cleaning or replace
Model selected correct on the transmitter and carb. in start position? -> happens more oftne then you would believe...
It won't run, can't set up or any other strange things:
Carb. become loose -> remount it
Tank isn't getting pressure -> Check the pressure hose from the exhaust to the tank, check the tightness of the fuel system
Fuel filter blocker -> Disassembling and cleaning or replace
Needle de-adjusted -> set it up new
This all should lead you to an engine which is running reliable, smooth, with a lot of power and that over a very long time:
And who read the above instructions very carefully also know now what needle needs to be turned in what direction after seeing that video ;).