problem here (esc 120)

[Johnc]

Running my stock Zonda (sss 2074 2075kv, b&s x440 props, 4s 50c, 5000mah to each ESC, basically each motor is independent of each other), after 1min it came to a quick slow down, shut down, retrieved it, opened hatch and found one of the one wires coming out of one ESC had "desoldered" itself from the inside of the esc, why? I don't understand (don't think I was over propped or over "S") Would that reparable by me? I don't know and just wondering if it possible. Would need to know by the pros if its feasible.

Also, a little off the subject, was running MC with an sss 2074 2200 (yea I know, I have a few of them motors) Hobbyking 120 ESC, 42 55 grim racer B&S prop. Had a couple of 2s 5000mah but "25c" hard cases, so I ran a total 4s. Ran them for about 3min in an oval (not flat out in turns) and a slow down for one lap. One of the hard cases was totally expoloded apart. I'm guessing it was of the 25c. Motor taking more than the battery could give??

Oh Well, Live and learn,

John

[Johnc]

ttt

[Bp9145]

First for the esc if the circuit board isn't fried it's possible to solder back the wire but you have to be careful soldering it back on. You have to solder the wire as fast as possible so you don't put excessive heat on the circuit board or you will destroy it yourself. You're going to have to open it up and see if all that's really happened was a wire desoldering itself and no further damage to that esc. I'm assuming the esc is a SK120A as you mentioned stock. Check your cooling line that goes on that esc as it might not be getting water passing through. . .clogged, kinked line maybe? Was the motor and battery also hot? Also, it could have as easily as a bad soldering connection on that point. It sometimes happen coming from the factory where they soldered it poorly. But if all that has happened was the wire desoldered then yes you can solder it back on. But usually the only thing that I've soldered on an esc are connectors, extra caps or an external bec. However, I have heard that others have tried desoldering the common 12AWG wires on an esc and soldering bigger 8AWG which I don't know why they would risk damaging the circuit board.
As for the one of the batteries exploding, well, first off I wouldn't recommend using hard packs on fe boats. The hard cases will prevent the battery from swelling and then puff. Hard packs are normally good for rc cars so that it protects the battery from getting punctured from pebbles, sticks or whatever that could come in contact with the battery and puncture it. In boats there are no hard objects that will come in contact with the batteries so the chances of getting punctured are unlikely unless something comes loose inside. Then fe boats draw a lot of amps that's why it's recommended to get at least 45C or higher and higher the better. Since most likely your 25C battery couldn't keep up with the amp draw it swelled and being in a hardcase it burst. I'd recommend staying away from hard packs although, I will admit I've used it myself but I know my boat setups and the amp draw. Get higher C rating batteries and definitely not hard packs.