Help! Esc extremely hot!
 

Hello all. Let me first say, I'm new to crawling/trailing and new to these forums! I picked up as my starter crawler, a little CC-01 Unimog. Now, I'm a converted Nitro (savage) guy to electric and know a little bit about electronics, but not a ton.

I picked up a used ESC from a friend of mine. It's a LRP Automatic Runner Reverse (the waterproof one). I also but in a 4000mAh LiPo battery (deans ends). I was just running the guy around in my landscaping in the back yard and the ESC smells hot and is very hot to the touch (I use heat at my work everyday, so my hands aren't sensitive). Is this something I should be worried about? My good friend who owns the LHS didn't mention anything about the battery being too big for the ESC.

Any help is greatly appreciated and desperately needed!

P.S. It has the stock (27 turn?) motor in the crawler. (I also use crawler to describe crawlers and trail trucks)

Could be your gearing. There are several things that could cause a hot esc...

Was the motor hot too? How about the battery? Any drag on the drivetrain? Hows the gear mesh?

Well the gearing is stock, I'm not too sure what the stock hearing is, but I can figure it out. As for the motor, the motor gets pretty hot as well. The only drag I can think of, is that we locked the front diff (removed the one gear spider gear). When I say esc, I mean the cooling fins on top, since the esc is so small, those fins seem to heat everything around it. I'm thinking of putting a 55turn motor in soon, would this help the heat problem?

if the motor is getting hot there must be some binding somewhere. with the motor removed does everything spin easy? that esc shouldnt get warm just from the motor unless it was closer to it turn limit so a 55t wont do much as it will likely get hot as well.

Nothings binding when I take the motor out. This is a brand new rig, never been run. The only thing we've done is put bigger tires on it, I went to the LHS and we're going to try putting on a different ESC and see if that will remedy the problem (or even just make it better).

you say stock motor, would this be a stock motor with 24 deg of timing, or stock with the truck....when i tried running a stock racing motor with locked 24 deg of timing, everything got hot.

EDIT: duuuude beat me on the gear mesh.

Its gotta be one of these...

Gear mesh is too tight.
Gear ratio is too high.
Motor timing is wrong.

If your lhs suggested a new esc, you need to find another lhs. I highly doubt the stock setup isn't capable of handling a 27t...

Did not see a reference to the number of cell lipo you are using. Double check to make sure the speed controller can handle the voltage you are using. Especially if you've upped the wheel/tire size.

im presuming its a 2s lipo since i have that same esc and i tried a 3s lipo and it wouldnt even work with it so i doubt he is over volting it.

A buddy of mine is using the same ESC and his gets really hot as well, he's running a stock silver can motor as well. The gear ratio seems to be a little high though, I was thinking that the lipo (2s/7.4v) might be pushing too much power through the ESC/motor. We're going to try changing the pinion, and I'm going to pick up a different ESC/motor next week (a buddy is lending me the ESC until the order comes through).