Would you rebuild it or lay it to rest
07-16-2012, 06:32 AM
#1
Would you rebuild it or lay it to rest
Ok guys I had a bad weekend. It was a big war bird show in the Columbus OH area, and lets just say I should of seen the signs. While trying to start my TopFlight Gaint P51 with Kelo muffler set up, she would not had start, after 30 flips, my New DX8 alarm started going off saying low voltage on the TX pack, wich made no since as I put it on the charger all last night.
Took the pack out put it on my Hitec charger, and changed the plug on the DLE55. After 10min my charger said the pack was good to go, and only put in 30mha back in. I didn't think anything of it, as I put it back in the reciver it showed full voltage and i was felling real emberesded as there were 30 guys askeing me why she did not start and this was my frist event like this, I have only been flying for a little over ayear now, and I have never seen a reciver pack go bad. She started up first flip, WOW lets rock, put her up and after 8 min of sweet flying I decied to do a low fly by at WOT about 1 foot off deck over the beans.
Well right in front of me, I saw the landing gear drop and the bird smak down, it was very bad!
The Kelo Muffl seems fine, but it hit the head so hard it broke the case in 2 peaces to where you can see the crank. The motor was almost 100ft from the remains of the body as it did not nose in but try to land at full speed in the bean feild. The xora 23X8 prop was broken and the cheap stock nose cone was beat up bad.
This was my fav motor and I hate to put here down. I will post a pic tonight.
If it was your motor, what parts would you replace? The head look ok supprizing.
When I got home I noticed one of the batters in the TX got so hot it melted the plastic and it was only showing 3v.
Thanksmike
Took the pack out put it on my Hitec charger, and changed the plug on the DLE55. After 10min my charger said the pack was good to go, and only put in 30mha back in. I didn't think anything of it, as I put it back in the reciver it showed full voltage and i was felling real emberesded as there were 30 guys askeing me why she did not start and this was my frist event like this, I have only been flying for a little over ayear now, and I have never seen a reciver pack go bad. She started up first flip, WOW lets rock, put her up and after 8 min of sweet flying I decied to do a low fly by at WOT about 1 foot off deck over the beans.
Well right in front of me, I saw the landing gear drop and the bird smak down, it was very bad!
The Kelo Muffl seems fine, but it hit the head so hard it broke the case in 2 peaces to where you can see the crank. The motor was almost 100ft from the remains of the body as it did not nose in but try to land at full speed in the bean feild. The xora 23X8 prop was broken and the cheap stock nose cone was beat up bad.
This was my fav motor and I hate to put here down. I will post a pic tonight.
If it was your motor, what parts would you replace? The head look ok supprizing.
When I got home I noticed one of the batters in the TX got so hot it melted the plastic and it was only showing 3v.
Thanksmike
07-16-2012, 07:45 AM
#3
RE: Would you rebuild it or lay it to rest
Mike, you sound like you are very low in experience and are paying a high price for it. You better learn the ins and outs of this hobby before you continue on in this destructive way and leave it frustrated. First you said that the transmitter pack was bad and then it was the receiver pack. It makes no difference which one it was. If you charged them the night before and you get an indication that a pack is bad at the field, go home and figure out what is wrong. You can not determine a battery's capacity by measuring its voltage. You have to cycle it. Using a battery by just measuring a battery pack without knowing its capacity is like diving in to a puddle of water just because you see the surface. It sounds like you drilled a very nice plane in to the ground. Sorry to hear about it but it’s your own fault. Learn from this experience and don't repeat it. I also apologize for the lecture but I hope this helps in the future. Dan.
07-16-2012, 08:02 AM
#4
RE: Would you rebuild it or lay it to rest
All spoken with the best of interests and should be taken as such. Hopefully he WILL learn from this painful experience and recognise the tell tale signs that we sometimes get that something is amiss before tragedy strikes.
Karol
Karol
07-16-2012, 08:13 AM
#5
RE: Would you rebuild it or lay it to rest
Bummer on the crash. My condolences. Seeing some pics is useful as maybe it isn't as bad as it looks.
But my general rule of thumb is when the cost to repair exceeds 50% of the cost of a new engine, then it is usually best to go new instead.
But sometimes one gets lucky and finds a donor parts engine with parts one can use to repair a badly crashed engine with too.
Some engines have good parts availability and the parts aren't too badly priced too.
Now if you have to pay to have someone repair your engines, then yes it can get expensive fast then.
Performing your own repairs can allow you to repair engines that would otherwise be relegated to the scrap bin.
I normally use a Expanded scale voltmeter to check my battery packs from time to time. I have been surprised before when a pack I thought I had charged had gone bad on me too. It is well worth the money and they don't cost much to get a expanded scale voltmeter. The better ones load the battery pack to give you a even more reliable reading too.
But my general rule of thumb is when the cost to repair exceeds 50% of the cost of a new engine, then it is usually best to go new instead.
But sometimes one gets lucky and finds a donor parts engine with parts one can use to repair a badly crashed engine with too.
Some engines have good parts availability and the parts aren't too badly priced too.
Now if you have to pay to have someone repair your engines, then yes it can get expensive fast then.
Performing your own repairs can allow you to repair engines that would otherwise be relegated to the scrap bin.
I normally use a Expanded scale voltmeter to check my battery packs from time to time. I have been surprised before when a pack I thought I had charged had gone bad on me too. It is well worth the money and they don't cost much to get a expanded scale voltmeter. The better ones load the battery pack to give you a even more reliable reading too.
07-16-2012, 08:30 AM
#6
RE: Would you rebuild it or lay it to rest
I do agree to a point as an ESV can be a very useful tool when dealing with Nicads or NimH batteries, but are just about useless when dealing with A123 or Lipo batteries.
Karol
Karol
07-16-2012, 10:09 AM
#7
RE: Would you rebuild it or lay it to rest
Thanks guys,
I was refering to the fact the TX pack was a 4 cell nicad wich is what I used to use are reciver packs and still use them to power my igniton controlers. I have never seen one go bad.
It looks like Ineed to get one of these testers your talking about, i just have a litte bar gauge that I plug in.
Here are the motor pics, Im a wrench turner in the Army so I can do my own work, but I just wanted to know what parts you guys would order? Would you replace the head?
This has been a great motor and I don't want to see it go.
SO I don't want to start anothere posting but while I was there I picked up a GP P-17 bi plane from a guy. He said he has never flown it but has run the motor up and down a few times.
The ignition controler shows it dose 4.8/6 volts would you leave the 5 cell nicad pack he has connected up for the ignition? Everything eles I have useing a standard 4.8 pack.
Thanks
Mike
I was refering to the fact the TX pack was a 4 cell nicad wich is what I used to use are reciver packs and still use them to power my igniton controlers. I have never seen one go bad.
It looks like Ineed to get one of these testers your talking about, i just have a litte bar gauge that I plug in.
Here are the motor pics, Im a wrench turner in the Army so I can do my own work, but I just wanted to know what parts you guys would order? Would you replace the head?
This has been a great motor and I don't want to see it go.
SO I don't want to start anothere posting but while I was there I picked up a GP P-17 bi plane from a guy. He said he has never flown it but has run the motor up and down a few times.
The ignition controler shows it dose 4.8/6 volts would you leave the 5 cell nicad pack he has connected up for the ignition? Everything eles I have useing a standard 4.8 pack.
Thanks
Mike
07-16-2012, 10:27 AM
#8
RE: Would you rebuild it or lay it to rest
If the crank is straight, looks like you need a crank case and cylinder, the head should be fine as long as no fins were broke.
For the flight pack, any 4 cell 2000 mah pack will work. The ignitions are sensitive to voltage and too many reports of the ignition failing from using a 5 cell pack, unless you use a regulator to keep it under 5 volts.
I use a load tester from Tower to check my packs before each flight. It puts a small load, about 300mah on the pack and reports back with a bar graph. I dont fly if one bar exists.
When you described the crash though, you said the flight pack for the ignition was the one that was low, so why did the landing gear drop? If the engine quit, you would still maintain control because the RX should have it's own pack, unless you shared, then in that case, Bad Move! Sounds like you had more than just an ignition failure, if it were, the engine would have just quit, and since you were high speed you should have still maintained control to at least get it down in one piece. I have had an engine quit on a high speed and was able to bring it down on the runway. Traded speed for some altitude, ruddered over to bring it around and brought it down. Love stall turns when you need them the most.
07-16-2012, 11:07 AM
#9
RE: Would you rebuild it or lay it to rest
Sorry it must of been the way I wrote it.
The only battery I was haveing a hard time with was the one for the TX the 4 cell nicad.
Like I said my Tx when off said low voltage. SO I put the 4 cell pack from the TX on the charger then a few min later the charger said it was good.
I put it back in then after 8 or so min of flying the landing gear droped and the motor turn off then it hit the ground as it was only a little over a foot off the ground anyway.
I never looked at the TX after the crash was to upset. After the crash I was not sure what happend. All guys said I had the Spectrum black out of death and thats why they all use Futabas.
After the crash I still flew my Little scale Little bird Trex450 with tow missiles with no issues. That why I thought it was somehing in the bird that was bad not the TX pack.
After my flight with the Trex 450 I bound it up to my New Little 130X Heli started flying then lost control and the TX was turned off!
Thats when I found the one cell in the TX pack got hot and mealted the covering.
IT was the weardest day ever for sure.
On the motor You guys think just a crank case?
The only battery I was haveing a hard time with was the one for the TX the 4 cell nicad.
Like I said my Tx when off said low voltage. SO I put the 4 cell pack from the TX on the charger then a few min later the charger said it was good.
I put it back in then after 8 or so min of flying the landing gear droped and the motor turn off then it hit the ground as it was only a little over a foot off the ground anyway.
I never looked at the TX after the crash was to upset. After the crash I was not sure what happend. All guys said I had the Spectrum black out of death and thats why they all use Futabas.
After the crash I still flew my Little scale Little bird Trex450 with tow missiles with no issues. That why I thought it was somehing in the bird that was bad not the TX pack.
After my flight with the Trex 450 I bound it up to my New Little 130X Heli started flying then lost control and the TX was turned off!
Thats when I found the one cell in the TX pack got hot and mealted the covering.
IT was the weardest day ever for sure.
On the motor You guys think just a crank case?
07-16-2012, 11:55 AM
#11
Senior Member
Join Date: Jan 2007
Location: Lancaster,
NY
Posts: 1,550
Likes: 0
Received 0 Likes
on
0 Posts
RE: Would you rebuild it or lay it to rest
Are you charging the tx pack with the proper setting? A nicad or nimh will take a long time to charge at 50mw. Sounds like the charger melted your cell.
07-16-2012, 01:23 PM
#12
RE: Would you rebuild it or lay it to rest
ORIGINAL: RCPAUL
That TX only uses a 4.8V pack!?Paul
That TX only uses a 4.8V pack!?Paul
Yes a DX8 only comes with a 2000mah 4.8v pack you can by an upgreaded 2s lipo for $74.
So I gess the one cell being bad, and completly dieing on me the pack provied such low power not to stay on.
The DX8 also has a charger built into it, but you have to change your setting from 4.8 to 2s Lipo
I have read with the 4000mah 2s lipo you can get 60hours of the TX being on before needed recharged.
07-16-2012, 02:34 PM
#13
RE: Would you rebuild it or lay it to rest
Regarding the engine, with the crankcase all busted up and the cylinder head pretty much chewed up, I would opt for a replacement engine and keep this one for possible spares down the road.
For ignition power I stick to using a 4.8 volt battery pack, as regulators that are used to regulate higher voltage batteries are quite prone to failure and whenever that occurs the ignition usually gives up the ghost too.
Karol
For ignition power I stick to using a 4.8 volt battery pack, as regulators that are used to regulate higher voltage batteries are quite prone to failure and whenever that occurs the ignition usually gives up the ghost too.
Karol
07-16-2012, 03:43 PM
#16
RE: Would you rebuild it or lay it to rest
Is anybody else as confused as I am about his "Tx" pack, a 4 cell nicad? I admit I am not familiar with Dx systems. I have never heard of a transmitter running off of 4.8v, which is a 4 cell nicad. I think you must have the terms Tx and Rx confused.
Also it is never a good idea to fast charge a nicad for aircraft. Only took 30ma of charge? Huh? What?
Replace that engine with a new one though.
Also it is never a good idea to fast charge a nicad for aircraft. Only took 30ma of charge? Huh? What?
Replace that engine with a new one though.
07-16-2012, 03:49 PM
#17
Senior Member
My Feedback: (1)
Join Date: Jun 2008
Location: Haltom City,
TX
Posts: 391
Likes: 0
Received 0 Likes
on
0 Posts
RE: Would you rebuild it or lay it to rest
One key in your description of the events that bothers me is this: when a 2000 mah pack took only 30 ma after the TX reported it low should have set off a huge red flag. If in fact the TX battery was low it should have taken many more milliamps to fully charge as you reported it a 2000 mah capacity battery. When it short charged ( only accepted a small charge ) it will only last a really short period of time. Some packs ( especially NIMH ) do this when first placed in service and some manufactures suggest cycling the new pack to insure they are good.
What I'm saying is that if you suspect a "short" charge, look for a reason. Is it battery capacity or is there really a problem with the TX ( or in whatever device the battery is being used )
edited for spelling[>:]
What I'm saying is that if you suspect a "short" charge, look for a reason. Is it battery capacity or is there really a problem with the TX ( or in whatever device the battery is being used )
edited for spelling[>:]
ORIGINAL: mikes68charger
Yes a DX8 only comes with a 2000mah 4.8v pack you can by an upgreaded 2s lipo for $74.
So I gess the one cell being bad, and completly dieing on me the pack provied such low power not to stay on.
The DX8 also has a charger built into it, but you have to change your setting from 4.8 to 2s Lipo
I have read with the 4000mah 2s lipo you can get 60hours of the TX being on before needed recharged.
ORIGINAL: RCPAUL
That TX only uses a 4.8V pack!?Paul
That TX only uses a 4.8V pack!?Paul
Yes a DX8 only comes with a 2000mah 4.8v pack you can by an upgreaded 2s lipo for $74.
So I gess the one cell being bad, and completly dieing on me the pack provied such low power not to stay on.
The DX8 also has a charger built into it, but you have to change your setting from 4.8 to 2s Lipo
I have read with the 4000mah 2s lipo you can get 60hours of the TX being on before needed recharged.
07-16-2012, 04:00 PM
#19
RE: Would you rebuild it or lay it to rest
Your very right that is the sign I missed becouse I was to emberessed with my bird not starting.
I gess I will just get a new motor. Thanks mike
ORIGINAL: bgw45
One key in your description of the events that bothers me is this: when a 2000 mah pack took only 30 ma after the TX reported it low should have set off a huge red flag. If in fact the TX battery was low it should have taken many more milliamps to fully charge as you reported it a 2000 mah capacity battery. When it short charged ( only accepted a small charge ) it will only last a really short period of time. Some packs ( especially NIMH ) do this when first placed in service and some manufactures suggest cycling the new pack to insure they are good.
What I'm saying is that if you suspect a "short" charge, look for a reason. Is it battery capacity or is there really a problem with the TX ( or in whatever device the battery is being used )
edited for spelling[>:]
One key in your description of the events that bothers me is this: when a 2000 mah pack took only 30 ma after the TX reported it low should have set off a huge red flag. If in fact the TX battery was low it should have taken many more milliamps to fully charge as you reported it a 2000 mah capacity battery. When it short charged ( only accepted a small charge ) it will only last a really short period of time. Some packs ( especially NIMH ) do this when first placed in service and some manufactures suggest cycling the new pack to insure they are good.
What I'm saying is that if you suspect a "short" charge, look for a reason. Is it battery capacity or is there really a problem with the TX ( or in whatever device the battery is being used )
edited for spelling[>:]
ORIGINAL: mikes68charger
Yes a DX8 only comes with a 2000mah 4.8v pack you can by an upgreaded 2s lipo for $74.
So I gess the one cell being bad, and completly dieing on me the pack provied such low power not to stay on.
The DX8 also has a charger built into it, but you have to change your setting from 4.8 to 2s Lipo
I have read with the 4000mah 2s lipo you can get 60hours of the TX being on before needed recharged.
ORIGINAL: RCPAUL
That TX only uses a 4.8V pack!?Paul
That TX only uses a 4.8V pack!?Paul
Yes a DX8 only comes with a 2000mah 4.8v pack you can by an upgreaded 2s lipo for $74.
So I gess the one cell being bad, and completly dieing on me the pack provied such low power not to stay on.
The DX8 also has a charger built into it, but you have to change your setting from 4.8 to 2s Lipo
I have read with the 4000mah 2s lipo you can get 60hours of the TX being on before needed recharged.
07-16-2012, 05:48 PM
#21
RE: Would you rebuild it or lay it to rest
Only guessing here because I don't own a Spectrum; but it sounds like you had your failsafe set up so it did what it should do when there is no signal coming from the transmitter, it goes to low throttle or no throttle and I guess it could drop the gear, or it could be just what happens when you turn off your transmitter before the receiver, all the servos go to full throw. Did you have some kind of optical kill switch? That would kill the engine with out a signal. That whole 4.8 v transmitter battery never made since to me. At least on an 8cell or lipo if you loose a cell you still have some voltage. Sorry man 
hate to see such a loss. I have the pt- 17 also and you will enjoy that, but don't plan on putting a 55 on her, the DLE20 works just great. Iwould buy a new engine and save this one for parts. Painful lesson for sure, but I would study some more about batteries and their upkeep. A good source of info here. http://www.hangtimes.com/rcbattery_faq.html
hate to see such a loss. I have the pt- 17 also and you will enjoy that, but don't plan on putting a 55 on her, the DLE20 works just great. Iwould buy a new engine and save this one for parts. Painful lesson for sure, but I would study some more about batteries and their upkeep. A good source of info here. http://www.hangtimes.com/rcbattery_faq.html
07-16-2012, 05:56 PM
#22
My Feedback: (2)
RE: Would you rebuild it or lay it to rest
Sorry to hear about the crash.
You could try replacing the crankcase and rod (in case it's tweaked, generally they're not too expensive), but I'm not so sure how much faith I would have in that engine at that point? OK for a beater maybe?
You could try replacing the crankcase and rod (in case it's tweaked, generally they're not too expensive), but I'm not so sure how much faith I would have in that engine at that point? OK for a beater maybe?
07-16-2012, 06:12 PM
#23
RE: Would you rebuild it or lay it to rest
OK NOW it makes sense. The failsafe on the DX8 will set the servos to the position they were when first bound. So in your case, either low throttle or ignition off, and gear down.
The default battery in the DX8 is a 4 cell NIMH, and does take a long time to charge, it never if ever goes over 5 volts on my radio, and I am considering replacing it with the Lipo from Hobbyking, http://www.hobbyking.com/hobbyking/s...ter_Pack_.html
Now did you charge the pack in the TX or with an external charger? If in the TX, if still under warranty, send it in for repair.
Bugger, the pack is on backorder.
The default battery in the DX8 is a 4 cell NIMH, and does take a long time to charge, it never if ever goes over 5 volts on my radio, and I am considering replacing it with the Lipo from Hobbyking, http://www.hobbyking.com/hobbyking/s...ter_Pack_.html
Now did you charge the pack in the TX or with an external charger? If in the TX, if still under warranty, send it in for repair.
Bugger, the pack is on backorder.
07-16-2012, 06:40 PM
#24
My Feedback: (17)
Join Date: Jan 2004
Location: Jamestown,
TN
Posts: 188
Likes: 0
Received 0 Likes
on
0 Posts
RE: Would you rebuild it or lay it to rest
The DX8 comes with a 4 cell 2000 mah NiMH battery. The charging circuitry in the tx is pretty dumb, ie, it will not terminate the charge when battery is full (in NiMH mode). Since it charges the battery at 200ma, you should NEVER plug the DX8 in and charge it overnight. I suspect that is what you did and that cooked the one cell in the battery.
There are 2 ways to charge this battery. Either take it out of the radio and charge it on a smart charger (which I prefer) or just take the battery cover off, plug the charger in and periodically feel the battery. If it gets pretty warm, it is fully charged. Unplug and have fun.
Sorry to read about this. This is due to the 'amazing' spektrum engineering and their dumb charging circuitry. BTW, when using the $70+ lipo, the charging will stop when the battery gets full.
There are 2 ways to charge this battery. Either take it out of the radio and charge it on a smart charger (which I prefer) or just take the battery cover off, plug the charger in and periodically feel the battery. If it gets pretty warm, it is fully charged. Unplug and have fun.
Sorry to read about this. This is due to the 'amazing' spektrum engineering and their dumb charging circuitry. BTW, when using the $70+ lipo, the charging will stop when the battery gets full.
07-16-2012, 06:44 PM
#25
Join Date: Feb 2006
Location: polson, MT
Posts: 228
Likes: 0
Received 0 Likes
on
0 Posts
RE: Would you rebuild it or lay it to rest
It's the sign of things to come. My new Futaba 8J also uses 4.8, 6.0, or 6.6 volts.
I flew 4 10 minute flights yesterday and still had 5.2 volts on a 4.8 battery pack.
I flew 4 10 minute flights yesterday and still had 5.2 volts on a 4.8 battery pack.