Motor stopped working on TRX Stampede

[Domijan91]

Hey guys, so I have (well had) a team Orion core stock motor on my traxxas stampede. I was running it and noticed it was getting extremely hot and started to smoke from the motor. I initially thought it was because I had just replaced the brushes on the motor and the LHS said it would run a bit hit till it fully worn in the brushes. But after three or four runs it quit! It wouldn't go any more. This was the first time this motor and battery were run together as I just got the battery.

Since then I've been looking at getting a new motor fairly cheap as I am saving for the brushless conversion. Anyways, I was looking at the Titan 12t. After reading a bit about it I saw its not supposed to be used with over 8.4 volts.
That got me thinking. The battery I am using is 8.4 volts.

Could my motor have not been able to handle 8.4 volts? When I took the motor apart I noticed a couple of the windings inside were melted in half, would this be because of heat or too many volts? Can this be fixed.

Sorry for the length, just want to me thorough.

Thanks.

 

[MudSlinger33]

That is very possible. Too much current flowing through windings that are only rated for 7.4 volts will cause over heating.

 

[JoeMAXX]

A 7 cell battery pack will fry a motor only meant for 6 cell 7.4 volts they tend to overheat quick and yes it will melt the copper winds in the motor. Traxxas Titan 550 motors are built to handle more voltage since many of them come with a 7 Cell battery pack. I have been converting to brushless these days and found the best bang for the buck is the Duratrax 1/10 Element 3900kV Brushless System I cannot say the will run in a Traxxas but I have installed them into 2 of my AE B4s and they rock.

http://www3.towerhobbies.com/cgi-bin/wti0001p?&W=000243232&I=LXAZUP&P=K

 

[RLHraccing]

thats why i love the nitro world motor stop pull it apart clean it replace seals and rod maybe the sleeve then reinstall and run

 

[Greywolf74]

Electrics arent any harder than nitros its just a different set of things you have to learn to understand them.

 

[JoeMAXX]

One thing I will add to this post is always check your motor temps if they exceed over 130 Degrees you need to let them rest and cool or run a heat sink on them to keep them cooler. Many brushed manufactures say you can run them up to 200 degrees but I believe that is too hot. I have an inexpensive infrared temp gauge to check my battery, motor and engine temps cost about $20.00 bucks and well worth the price when you look at the cost of replacing stuff.

Brushless motors should exceed not 135 Degrees and some Traxxas VXL Sensored Motors and ESC will shutdown when they reach this temperature I like to keep them around or below 100 degrees when running. This insures you will not damage them.

NiMh, NiCad and LiPo battery packs also should never really get hotter then 100 degrees when charging, running or discharging over 140 degrees you can damage the cells in the pack. I like to stay well below that limit to avoid exploding a cell. I have melted the plastic on my NiMh battery packs in the past when I was just learning about NiMh packs when they first came out. If I have a 3000 battery I will charge it at rate of 1.5 on my chargers. I always choose half of what the battery pack is when charging to avoid getting them too hot.

LiPo Packs are much more dangerous and can catch fire if you do not properly take care of them. I always charge them in a fire proof bag which you can buy for about $20.00 bucks. The newer chargers come with a balancer which keeps the LiPo packs at the same voltage when charging or discharging. Again I charge them at half of what the pack is all my LiPo packs are 5000 packs so I charge them at at rate of 2.5 on my charger.

I also learned recently you should never allow a Lipo battery pack to fall below 3 volts per pack when running or discharging them. I bought a balancer for about $20.00 bucks to check my LiPo battery packs to check the voltage. This also will balance the cells before you charge them again. Many newer ESCs that are LiPo compatable have a fail safe built into them but not all do.

http://batteryuniversity.com/learn/article/charging_at_high_and_low_temperatures

 

[trax de max]

One thing I will add to this post is always check your motor temps if they exceed over 130 Degrees you need to let them rest and cool or run a heat sink on them to keep them cooler. Many brushed manufactures say you can run them up to 200 degrees but I believe that is too hot. I have an inexpensive infrared temp gauge to check my battery, motor and engine temps cost about $20.00 bucks and well worth the price when you look at the cost of replacing stuff.

Brushless motors should exceed not 135 Degrees and some Traxxas VXL Sensored Motors and ESC will shutdown when they reach this temperature I like to keep them around or below 100 degrees when running. This insures you will not damage them.

NiMh, NiCad and LiPo battery packs also should never really get hotter then 100 degrees when charging, running or discharging over 140 degrees you can damage the cells in the pack. I like to stay well below that limit to avoid exploding a cell. I have melted the plastic on my NiMh battery packs in the past when I was just learning about NiMh packs when they first came out. If I have a 3000 battery I will charge it at rate of 1.5 on my chargers. I always choose half of what the battery pack is when charging to avoid getting them too hot.

LiPo Packs are much more dangerous and can catch fire if you do not properly take care of them. I always charge them in a fire proof bag which you can buy for about $20.00 bucks. The newer chargers come with a balancer which keeps the LiPo packs at the same voltage when charging or discharging. Again I charge them at half of what the pack is all my LiPo packs are 5000 packs so I charge them at at rate of 2.5 on my charger.

I also learned recently you should never allow a Lipo battery pack to fall below 3 volts per pack when running or discharging them. I bought a balancer for about $20.00 bucks to check my LiPo battery packs to check the voltage. This also will balance the cells before you charge them again. Many newer ESCs that are LiPo compatable have a fail safe built into them but not all do.

http://batteryuniversity.com/learn/article/charging_at_high_and_low_temperatures

Are you sure your figures are correct.
Charging a pack at the recommended C rate or 1/2, 1/4 makes no difference if you have a poor charger, damage occurs when cell voltage is low and when voltage is high. Your better off charging at 1C and charging to 4.195V per cell

 

[Metalhead Matt]

I run 12t Titians on 14.4 volts. Have been for a few years. Geared properly of coarse. Gearing and/or a worn out motor was the cause of death. Thunder Tiger makes a 15t 550 that would be a little more forgiving when it comes to gearing. You will always have to gear down when running on grass if it's part of your terrain.