Shutting down the engine
07-10-2008 | 10:29 AM
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From: Rochester,
NY
Shutting down the engine
If you are supposed to set your throttle control on the radio so the engine idles when all the way down, how are you supposed to stop the engine at the end of a flight, but using the trim?
If so, it seems like you would always be chasing the low throttle setting. Is there another way to shut down an engine using the other controls on the radio, or with another device? Thanks.
If so, it seems like you would always be chasing the low throttle setting. Is there another way to shut down an engine using the other controls on the radio, or with another device? Thanks.
07-10-2008 | 10:39 AM
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From: Chesnee,
SC
RE: Shutting down the engine
Many radios have an engine kill button. You set it up to travel -15% or so, so the servo travels BELOW the minimum position and closes the throttle.
If you don't have this feature and have analog trims, we set the idle speed with the throttle trim 1/2 to 3/4 way up so when you want to kill the engine, you pull the trim down.
If you have digital trims but no kill button, then put your finger over the exhaust. It loads the engine with fuel a bit, but it's safer than putting your finger over the carb. Sometimes you can pinch the fuel line too, but that depends on your setup.
Setting your throttle stick so the lowest position kills the throttle is probably asking for trouble.
Good luck!
If you don't have this feature and have analog trims, we set the idle speed with the throttle trim 1/2 to 3/4 way up so when you want to kill the engine, you pull the trim down.
If you have digital trims but no kill button, then put your finger over the exhaust. It loads the engine with fuel a bit, but it's safer than putting your finger over the carb. Sometimes you can pinch the fuel line too, but that depends on your setup.
Setting your throttle stick so the lowest position kills the throttle is probably asking for trouble.
Good luck!
07-10-2008 | 10:41 AM
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RE: Shutting down the engine
Cappaj1,
Ok, old non-computer radios first. On these radios you set the engine throttle so that it is completely closed when the stick is fully down and the trim tab is all the way down as well. Then when you fly you move the trim tab up to where the engine idles. While it may sound like you are chasing the idle it's really not that bad. I move the trim tab all the way up and then when the engine starts I come back down to where it idles. When I'm done flying I simply use the trim tab to it's lowest setting which will kill the engine.
For computer radios with digital trims. Most of these will have either a throttle cut button/switch preprogrammed, or give you the ability to set up a throttle cut. These you simply activate the throttle cut which will close the barrel of the carb and kill the engine.
Hope this helps
Ken
Ok, old non-computer radios first. On these radios you set the engine throttle so that it is completely closed when the stick is fully down and the trim tab is all the way down as well. Then when you fly you move the trim tab up to where the engine idles. While it may sound like you are chasing the idle it's really not that bad. I move the trim tab all the way up and then when the engine starts I come back down to where it idles. When I'm done flying I simply use the trim tab to it's lowest setting which will kill the engine.
For computer radios with digital trims. Most of these will have either a throttle cut button/switch preprogrammed, or give you the ability to set up a throttle cut. These you simply activate the throttle cut which will close the barrel of the carb and kill the engine.
Hope this helps
Ken
07-10-2008 | 10:43 AM
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From: Mosinee,
WI
RE: Shutting down the engine
most computer radios have a throtle cut which just goes to low throtle trim. You set the throtle to the idle you want at neutral trim and then to cut stop the engine just pull the trim lever all the way down or hit the throtle cut, which does the same thing. Usauly radios with digital trims will have a throtle cut button which simply overrides the trim and pulls the throtle all the way down to close the opening and shut the engine off.
07-10-2008 | 11:37 AM
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From: Rochester,
NY
RE: Shutting down the engine
ORIGINAL: RCKen
Cappaj1,
Ok, old non-computer radios first. On these radios you set the engine throttle so that it is completely closed when the stick is fully down and the trim tab is all the way down as well. Then when you fly you move the trim tab up to where the engine idles. While it may sound like you are chasing the idle it's really not that bad. I move the trim tab all the way up and then when the engine starts I come back down to where it idles. When I'm done flying I simply use the trim tab to it's lowest setting which will kill the engine.
For computer radios with digital trims. Most of these will have either a throttle cut button/switch preprogrammed, or give you the ability to set up a throttle cut. These you simply activate the throttle cut which will close the barrel of the carb and kill the engine.
Hope this helps
Ken
Cappaj1,
Ok, old non-computer radios first. On these radios you set the engine throttle so that it is completely closed when the stick is fully down and the trim tab is all the way down as well. Then when you fly you move the trim tab up to where the engine idles. While it may sound like you are chasing the idle it's really not that bad. I move the trim tab all the way up and then when the engine starts I come back down to where it idles. When I'm done flying I simply use the trim tab to it's lowest setting which will kill the engine.
For computer radios with digital trims. Most of these will have either a throttle cut button/switch preprogrammed, or give you the ability to set up a throttle cut. These you simply activate the throttle cut which will close the barrel of the carb and kill the engine.
Hope this helps
Ken
07-10-2008 | 11:45 AM
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RE: Shutting down the engine
ORIGINAL: cappaj1
Thanks, guys. I checked the Futaba 7C manual - my 7C is on it's way - just now and it does have the TH-CUT feature which stops the engine by flipping a switch at idle. It says when the throttle is up the switch can't accidentally cut the engine - it only works at low throttle settings. Cool.
ORIGINAL: RCKen
Cappaj1,
Ok, old non-computer radios first. On these radios you set the engine throttle so that it is completely closed when the stick is fully down and the trim tab is all the way down as well. Then when you fly you move the trim tab up to where the engine idles. While it may sound like you are chasing the idle it's really not that bad. I move the trim tab all the way up and then when the engine starts I come back down to where it idles. When I'm done flying I simply use the trim tab to it's lowest setting which will kill the engine.
For computer radios with digital trims. Most of these will have either a throttle cut button/switch preprogrammed, or give you the ability to set up a throttle cut. These you simply activate the throttle cut which will close the barrel of the carb and kill the engine.
Hope this helps
Ken
Cappaj1,
Ok, old non-computer radios first. On these radios you set the engine throttle so that it is completely closed when the stick is fully down and the trim tab is all the way down as well. Then when you fly you move the trim tab up to where the engine idles. While it may sound like you are chasing the idle it's really not that bad. I move the trim tab all the way up and then when the engine starts I come back down to where it idles. When I'm done flying I simply use the trim tab to it's lowest setting which will kill the engine.
For computer radios with digital trims. Most of these will have either a throttle cut button/switch preprogrammed, or give you the ability to set up a throttle cut. These you simply activate the throttle cut which will close the barrel of the carb and kill the engine.
Hope this helps
Ken
Ken
07-10-2008 | 11:45 AM
#7
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RE: Shutting down the engine
About that "Chasing the low throttle setting", it seems like I'm often changing the trim tab after flying out a half tank or so. Sometimes not, sometimes the idle creeps up as the tank empties out. I see this on glow and gasoline engines.
No big deal, that's what trim tabs are for. Likewise the other trims, you may find yourself changing control trim, from time to time. I remember my old 4-star, the outside temperature would change the length of the plastic pushrods - and that would require a trim tab reset.
Good luck,
Dave Olson
No big deal, that's what trim tabs are for. Likewise the other trims, you may find yourself changing control trim, from time to time. I remember my old 4-star, the outside temperature would change the length of the plastic pushrods - and that would require a trim tab reset.
Good luck,
Dave Olson
07-10-2008 | 12:13 PM
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From: cando,
MO
RE: Shutting down the engine
Most times flying my trim is set to keep the throttle at a fairly descent idle. When landing you have to start trimming down as you are landing or right before I try to do it just as i am about to make approach already headed at the landing area. That way if you go to much and kill it or it just dies trimming it your already on final approach. That will help some if you kill it at least your headed right where you need to be headed.
07-10-2008 | 01:00 PM
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From: San Diego,
CA
RE: Shutting down the engine
DX6i uses the Throttle CUT button on top right, on the DX7 you use the Throttle recovery feature. This returns your Trim to what it was BEFORE you moved it all the way down to shut the engine.
07-10-2008 | 09:26 PM
#11
RE: Shutting down the engine
In the "bad ol days" I used to set the engine to idle ar the uppermost trim setting with the throttle stick bottomed out. Then I could thumb down the throttle to kill it and had a low idle for landing in between.
Now I have a low idle switch and a kill switch. Ah, technology.
Now I have a low idle switch and a kill switch. Ah, technology.
07-11-2008 | 01:13 AM
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From: Oklahoma City,
OK
RE: Shutting down the engine
ORIGINAL: cappaj1
Thanks, guys. I checked the Futaba 7C manual - my 7C is on it's way - just now and it does have the TH-CUT feature which stops the engine by flipping a switch at idle. It says when the throttle is up the switch can't accidentally cut the engine - it only works at low throttle settings. Cool.
Thanks, guys. I checked the Futaba 7C manual - my 7C is on it's way - just now and it does have the TH-CUT feature which stops the engine by flipping a switch at idle. It says when the throttle is up the switch can't accidentally cut the engine - it only works at low throttle settings. Cool.
Yeah that's what the manual for my 6ex says too, but my throttle cut will work even if the throttle stick is at full throttle. [>:] If you don't set up your radio right and it won't kill it, there is a neat way of grabbing the spinner to kill it. I would suggest having someone experienced show you first, then maybe practice it later. It's a little scary.
07-11-2008 | 06:13 AM
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From: Tyler, TX TX
RE: Shutting down the engine
Another non-radio way of shutting it down, which I use on my car engines and several times on my planes, is to plug your exhaust. This causes the exhaust pressure to build up and choke the engine. If you choose to use this method, be careful, the muffler can/will get very hot, even with a properly tuned engine. Most of the time using this technique, I use my finger, but if the exhaust is either too hot, or it takes to long to kill the motor, put my finger in a rag if I have one handy.
07-11-2008 | 12:40 PM
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From: Oklahoma City,
OK
RE: Shutting down the engine
Get an exhaust deflector and the heat won't bother you. Got one on my savage and little plane to keep the oil away as much as possible.
07-11-2008 | 05:21 PM
#15
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RE: Shutting down the engine
ORIGINAL: brett65
Yeah that's what the manual for my 6ex says too, but my throttle cut will work even if the throttle stick is at full throttle. [>:] If you don't set up your radio right and it won't kill it, there is a neat way of grabbing the spinner to kill it. I would suggest having someone experienced show you first, then maybe practice it later. It's a little scary.
ORIGINAL: cappaj1
Thanks, guys. I checked the Futaba 7C manual - my 7C is on it's way - just now and it does have the TH-CUT feature which stops the engine by flipping a switch at idle. It says when the throttle is up the switch can't accidentally cut the engine - it only works at low throttle settings. Cool.
Thanks, guys. I checked the Futaba 7C manual - my 7C is on it's way - just now and it does have the TH-CUT feature which stops the engine by flipping a switch at idle. It says when the throttle is up the switch can't accidentally cut the engine - it only works at low throttle settings. Cool.
Yeah that's what the manual for my 6ex says too, but my throttle cut will work even if the throttle stick is at full throttle. [>:] If you don't set up your radio right and it won't kill it, there is a neat way of grabbing the spinner to kill it. I would suggest having someone experienced show you first, then maybe practice it later. It's a little scary.
Don
07-11-2008 | 05:27 PM
#16
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RE: Shutting down the engine
I may have missed it, but to get any of the closed throttle Kill methods to work, you have to be able to completly close the throttle. Every new engine I have used in the last three years came with the idle stop screw set to idle. not to the point you could stop the engine. Back off on this screw until you can fully close the barrel and not see any sign of an opening. Then back it off another 1/2 Turn. Now you can set your servo linkage so the stop end point reall will stop it.
One other point, set up your engine kill and idle with fresh fuel. I sat my last one up with the end of a jug and when I cut to the new jug, all bets were off for killing it. With the engine tuned well, it is susprising how long it will putt putt along when you really want it to stop.
Don
One other point, set up your engine kill and idle with fresh fuel. I sat my last one up with the end of a jug and when I cut to the new jug, all bets were off for killing it. With the engine tuned well, it is susprising how long it will putt putt along when you really want it to stop.
Don
07-11-2008 | 10:36 PM
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From: Rochester,
NY
RE: Shutting down the engine
ORIGINAL: jetmech05
stopping an aircraft engine on a regular basis by plugging the exhaust is just not a wise idea....
stopping an aircraft engine on a regular basis by plugging the exhaust is just not a wise idea....
I sure don't plan on doing that. I will be using the TH-CUT feature on my radio (when I get it)!
07-12-2008 | 07:58 PM
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From: Winnipeg,
MB, CANADA
RE: Shutting down the engine
I have the 7C and being new had no trouble with the th-cut feature. Use the end point on the throttle servo to set idle and then program the th-cut to close the carb just enough to stop the engine. This way if you hit the switch with anything other then idle speed the engine will keep running. Meaning at half throttle if you hit the switch you will hear the engine slow just a bit but because you are not at idle it will not quit. Remember though to set the switch back before flight, I left the th-cut on and couldn't figure out why my engine would not idle properly. I was ready to start adjusting the needles when I noticed the switch in the wrong position. If you forget the switch and turn the radio off and back on you will get a beep telling you the switch is in the wrong position. Getting close eh. LOL
07-13-2008 | 05:31 AM
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From: Rochester,
NY
RE: Shutting down the engine
ORIGINAL: Mikecam
I have the 7C and being new had no trouble with the th-cut feature. Use the end point on the throttle servo to set idle and then program the th-cut to close the carb just enough to stop the engine. This way if you hit the switch with anything other then idle speed the engine will keep running. Meaning at half throttle if you hit the switch you will hear the engine slow just a bit but because you are not at idle it will not quit. Remember though to set the switch back before flight, I left the th-cut on and couldn't figure out why my engine would not idle properly. I was ready to start adjusting the needles when I noticed the switch in the wrong position. If you forget the switch and turn the radio off and back on you will get a beep telling you the switch is in the wrong position. Getting close eh. LOL
I have the 7C and being new had no trouble with the th-cut feature. Use the end point on the throttle servo to set idle and then program the th-cut to close the carb just enough to stop the engine. This way if you hit the switch with anything other then idle speed the engine will keep running. Meaning at half throttle if you hit the switch you will hear the engine slow just a bit but because you are not at idle it will not quit. Remember though to set the switch back before flight, I left the th-cut on and couldn't figure out why my engine would not idle properly. I was ready to start adjusting the needles when I noticed the switch in the wrong position. If you forget the switch and turn the radio off and back on you will get a beep telling you the switch is in the wrong position. Getting close eh. LOL
07-13-2008 | 07:27 AM
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From: CAMDEN,
TN
RE: Shutting down the engine
ORIGINAL: Cyclic Hardover
RCKENs version is best for those with a basic 4 channel. Or just tip the tail up until the prop hit the ground! Sorry but I
just had to say it!
RCKENs version is best for those with a basic 4 channel. Or just tip the tail up until the prop hit the ground! Sorry but I
just had to say it!
I have seen it and it does work but I would not recommend it.
07-13-2008 | 08:37 AM
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From: Winnipeg,
MB, CANADA
RE: Shutting down the engine
ORIGINAL: cappaj1
Thanks for the tips. Just one thing I don't understand. If you use the end point of the throttle servo to set idle, how can it move behind that point to close the carb?
ORIGINAL: Mikecam
I have the 7C and being new had no trouble with the th-cut feature. Use the end point on the throttle servo to set idle and then program the th-cut to close the carb just enough to stop the engine. This way if you hit the switch with anything other then idle speed the engine will keep running. Meaning at half throttle if you hit the switch you will hear the engine slow just a bit but because you are not at idle it will not quit. Remember though to set the switch back before flight, I left the th-cut on and couldn't figure out why my engine would not idle properly. I was ready to start adjusting the needles when I noticed the switch in the wrong position. If you forget the switch and turn the radio off and back on you will get a beep telling you the switch is in the wrong position. Getting close eh. LOL
I have the 7C and being new had no trouble with the th-cut feature. Use the end point on the throttle servo to set idle and then program the th-cut to close the carb just enough to stop the engine. This way if you hit the switch with anything other then idle speed the engine will keep running. Meaning at half throttle if you hit the switch you will hear the engine slow just a bit but because you are not at idle it will not quit. Remember though to set the switch back before flight, I left the th-cut on and couldn't figure out why my engine would not idle properly. I was ready to start adjusting the needles when I noticed the switch in the wrong position. If you forget the switch and turn the radio off and back on you will get a beep telling you the switch is in the wrong position. Getting close eh. LOL
Well No expert but thats the beauty to the computer radio. The servo is not at the endpoint just the computer radio. You can close the carb completely with the endpoint but instead you back it off so it idles. That way the th-cut moves the servo that much more to shut the engine off and you can set that amount of movement as well. I tested mine so the th-cut would just close the carb, that way if you hit the th-cut switch while flying at say half throttle the th-cut movement isn't enough to stop the engine. Basically the th-cut amount of movement does not change whether your at half throttle or idle, just at idle the small amount of movement is enough to stop the engine while at half throttle it only slows it a little. I hope I'm not confusing you more. I know what I'm trying to say but not sure how to express it. I knew nothing 2 months ago and just worked on reading through the manual, at first it was very overwhelming but as you learn the simple things the more complex become easier. I kind of laugh at myself now for how I felt that I would never learn all this stuff. At first the manual can feel very complicated but take it one step at a time and it gets much easier. My first RC radio ever was a 7C so I had everything to learn all at once.
07-13-2008 | 10:43 AM
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From: Rochester,
NY
RE: Shutting down the engine
ORIGINAL: Mikecam
Well No expert but thats the beauty to the computer radio. The servo is not at the endpoint just the computer radio. You can close the carb completely with the endpoint but instead you back it off so it idles. That way the th-cut moves the servo that much more to shut the engine off and you can set that amount of movement as well. I tested mine so the th-cut would just close the carb, that way if you hit the th-cut switch while flying at say half throttle the th-cut movement isn't enough to stop the engine. Basically the th-cut amount of movement does not change whether your at half throttle or idle, just at idle the small amount of movement is enough to stop the engine while at half throttle it only slows it a little. I hope I'm not confusing you more. I know what I'm trying to say but not sure how to express it. I knew nothing 2 months ago and just worked on reading through the manual, at first it was very overwhelming but as you learn the simple things the more complex become easier. I kind of laugh at myself now for how I felt that I would never learn all this stuff. At first the manual can feel very complicated but take it one step at a time and it gets much easier. My first RC radio ever was a 7C so I had everything to learn all at once.
ORIGINAL: cappaj1
Thanks for the tips. Just one thing I don't understand. If you use the end point of the throttle servo to set idle, how can it move behind that point to close the carb?
ORIGINAL: Mikecam
I have the 7C and being new had no trouble with the th-cut feature. Use the end point on the throttle servo to set idle and then program the th-cut to close the carb just enough to stop the engine. This way if you hit the switch with anything other then idle speed the engine will keep running. Meaning at half throttle if you hit the switch you will hear the engine slow just a bit but because you are not at idle it will not quit. Remember though to set the switch back before flight, I left the th-cut on and couldn't figure out why my engine would not idle properly. I was ready to start adjusting the needles when I noticed the switch in the wrong position. If you forget the switch and turn the radio off and back on you will get a beep telling you the switch is in the wrong position. Getting close eh. LOL
I have the 7C and being new had no trouble with the th-cut feature. Use the end point on the throttle servo to set idle and then program the th-cut to close the carb just enough to stop the engine. This way if you hit the switch with anything other then idle speed the engine will keep running. Meaning at half throttle if you hit the switch you will hear the engine slow just a bit but because you are not at idle it will not quit. Remember though to set the switch back before flight, I left the th-cut on and couldn't figure out why my engine would not idle properly. I was ready to start adjusting the needles when I noticed the switch in the wrong position. If you forget the switch and turn the radio off and back on you will get a beep telling you the switch is in the wrong position. Getting close eh. LOL
Well No expert but thats the beauty to the computer radio. The servo is not at the endpoint just the computer radio. You can close the carb completely with the endpoint but instead you back it off so it idles. That way the th-cut moves the servo that much more to shut the engine off and you can set that amount of movement as well. I tested mine so the th-cut would just close the carb, that way if you hit the th-cut switch while flying at say half throttle the th-cut movement isn't enough to stop the engine. Basically the th-cut amount of movement does not change whether your at half throttle or idle, just at idle the small amount of movement is enough to stop the engine while at half throttle it only slows it a little. I hope I'm not confusing you more. I know what I'm trying to say but not sure how to express it. I knew nothing 2 months ago and just worked on reading through the manual, at first it was very overwhelming but as you learn the simple things the more complex become easier. I kind of laugh at myself now for how I felt that I would never learn all this stuff. At first the manual can feel very complicated but take it one step at a time and it gets much easier. My first RC radio ever was a 7C so I had everything to learn all at once.
Sounds like what your saying is when you set up the airplane you move the servo all the way by moving the stick all the way down, then connect your linkage to the carb to servo. But the servo is actually not all the way down as the computer in the radio is smart enough to leave a little more travel for the th-cut feature. Am I getting it now?
07-13-2008 | 11:19 AM
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From: Winnipeg,
MB, CANADA
RE: Shutting down the engine
Exactly. I made sure my throttle servo was centered and then I centered my carb. The arm on the carb has a screw and you can move the arm where you need it. There is a fair bit of extra room as when I was setting my end point I can close the throttle and keep going till the rod starts to bind. It has enough force that you can see the rod bend. The th-cut feature is just a set amount of extra travel to the throttle linkage. Works very well. Once you get used to the radio it gets much easier. The programing once you learn the system is not a problem. One hint I learned, if the radio does not program how it says in the manual then look into if you have it set on the right program. I tried to set up my th-cut and it wouldn't work. I tried by the book about 3 times and could get no extra movement. I started looking else where and found I had it set to a heli mode for that setting. Not sure how I did that but after setting it up in airplane mode the th-cut works just like in the book. Keep us posted.
