Took me 6 packs to...

[-=ADA$=-]

Burn ESC :D, i got tamiya TA-04 R tuned, with hi-tec pro ezx-r, and tamiya super stock motor type R.
The ESC was getting hot at first to i changed to highest gear ratio i had (that was possible to fit), and after i run about 5 packs, and today after running on parking lot, the car slowed down significantly. I thought it was dead pack, but after taking a glance, i noticed that after applying some throttle there was some smoke from ESC, after taking it home, i connected pack, and after applying very little throttle there was ALOT of smoke from ESC, and it wont run anymore.

Ive took apart case and noticed that probably one of fet's is smoked.

So my question is, could it be replaced? and where to get it and for how much. also on the edge theres like a silver "trace" thets burnt also (let me explain it to You using a picture :) ) is it possible to fix it??
http://img11.echo.cx/img11/7576/ezxr3kd.th.jpg (http://img11.echo.cx/my.php?image=ezxr3kd.jpg)

sorry for crappy quality - crappy camera :d
Thanks alot for help

[AudiTT-Quattro]

Without actually having it in my hand, I can't tell you very much and the picture isn't helping either. But yes, you can replace the FET provided that nothing else is damaged. For electronics supplies, check your local Yellowpages for a local dealer. If all else fails, www.digikey.com is a good place to start.

[Danno]

Why did You change to a higher gear ratio ? Unless You where trying to smoke the ESC on purpose ??

[Rtsbasic]

higher gear ratio = higher final drive ratio = less top speed/amp draw, making it easier on the controller. Gearing is reverse to most things - if you use a lower final drive ratio your geared steeper and have more top end than if your geared higher. Hope that makes sense.

[-=ADA$=-]

yeah, i changed to higher gear ratio (smaller pinion/bigger spur) cause ESC was becoming a bit hot at first. But apparently it didnt help. But maybe someone knows what type of transistors are these?? maybe i can replace it, but its odd to me, ive tried to connect my super rooster that i had in my crawler, and now the ESC is stone cold, but wires are very hot, even somewhat melted near plug (yea tamiya style for now) but its 23T motor, it shouldnt do it right??

[Rtsbasic]

A 23T motor can't pull enough amps to melt the connector i'd have thought (a good 19T will though), sounds like there's a short somewhere causing the heat buildup on the cables. Or something wrong with the motor. I have no idea what type of transitors they use unfortunately.

[Salica]

You should check that batterie pack that burned the esc that could be the cause of the problem. also check the motor make sure it good, have the right capacitors installed.

[-=ADA$=-]

batteries are good, im as sure as i can :D, but im not sure about capacitors, ive noticed that thers a little circuit board with 3 small square thingies (which i presumed are capacitors) but im not totaly sure.


And thats same thing i thought, 23T motor shouldnt make plugs melt (even if its tamiya style).

Is there any way i can examine motor, i cant take endbell off (there are bents in can that hold it)

[Rtsbasic]

You can remove the endbell even on sealed types, but it won't be race legal again. Just find a small enough screw driver or something similar and pry the tabs back. May also need to pry the endbell off around other spots to loosen it a bit.

The small circuit has 3 SM (surface mount) capacitors I'd assume, my Trinity P2K has a similar circuit, as does my Trinity D5 12x1.

To do a quick check on the motor, take the brush springs out, and see if the brushes are burnt (normally they're a copper colour or a silver colour, pending on what type they are). This also gives you a chance to look at the comm - if its shiny its still good. If not then you could use a comm stick on it without opening up the motor to clean it a bit. Also while the brushes are out spin the motor and see if there is any binding/resistance other than the magnetic field.
If the can's not ballraced you can oil the bushings, that will reduce the resistance in the motor increasing performance (also reduces the amount of amps that will be pulled, but I wouldn't have thought that would be a problem with a 23T).

[-=ADA$=-]

I still cant be sure if these are capacitors (no way to check though).

After looking at brushes (that was first thing i did), theyr still silver/copper colored, and comm looks shiny and almost new.

Ive tried to pry the tabs but i broke screwdriver trying, so i thought ill let them alone.

And i dont know how to recognize what is "normal megnetic field" - im mostly nitro guy, but if i spin the armature it will do 1-2 turns and stop. its rather hard to turn, and it turns in "steps". dunno how to explain it better.

But thanks alot for all help

[Danno]

higher gear ratio = higher final drive ratio = less top speed/amp draw, making it easier on the controller. Gearing is reverse to most things - if you use a lower final drive ratio your geared steeper and have more top end than if your geared higher. Hope that makes sense.
I`m thinking a "higher gear" or a numerically lower gear ratio , as in if you put your real car in low gear it will be running at a numerically higher gear ratio .
misunderstood , sorry

[Rtsbasic]

Turning in "steps" is good, it being hard to turn is also good, really there is only a problem if the turn isn't smooth. Its hard to explain due to the strength of the magnets in the can that cause it to turn in steps but if it turns and sounds bad while doing it then there's something wrong. I guess you could compare it to turning the flywheel in a nitro, if the engine is healthy and has good compression its a bit hard to turn but otherwise nice and smooth while it does. In an electric if it turns without any binding or bad noises then its all good most of the time. Doesn't sound like there's anything wrong with it though so I doubt the motor is the cause of the problem.

[-=ADA$=-]

if thats description of bad running, than it runs great, no scratch noises, or other than normal friction etc. Ill have to check other motor (just for the sake of it) to be sure, cause ive already tried second ESC, and 2 packs.

[loopy]

I had a 23t that even made my 8tESC very hot.
It was enough to make a 10t apex esc go into over temp cutoff.
I couldnt for the life of me work out why it did that, until i stuck it in my dyno charge unit and ran it at 4volt (reasonably high revs)for like an hr.I was watching the current draw no.s get lower as time went on. Its fine now so I can only assume the bushings were still too tight and as i ran it they loosened up some. :o