My old Mamba Max Pro started to smoke

[GotNoRice]

One of my trucks is an older model Traxxas Stampede 4x4 that is using a Mamba Max Pro (Older Castle ESC, predecessor to the Mamba X). I run it along with a 2400kv 36x74 motor on 3s and 4s. The truck had been on the shelf for about a year after a hard landing that broke a couple of teeth on the spur. After getting the new spur installed and putting the truck back together, I plugged in a battery to test the truck and even though the Mamba Max Pro started up like normal with the expected beeps, smoke also began to start coming out of the side of the ESC. I immediately pulled the plug on the battery.

I'm still not 100% sure what happened, but when I removed the heatsink, I noticed that the thermal paste was VERY dry and crusted. I guess that makes sense since I got the ESC 13+ years ago at this point. I cleaned everything as best as I could, used some computer CPU thermal paste, and put the heatsink back on. Surprisingly the ESC seems to work fine.

While I'm thrilled that the ESC still works, I can't help wonder what was smoking? Was it probably just the dry paste? Should I just continue using it until it stops working again or is it risky to keep using it?

 

[Tunedfrog]

.

 

[tntpoof]

Sounds like you smoked the ESC and it's time to replace it.

He said it works perfect after the smoke.. Id say your taking chances but you have the Dice hope you dont roll snake eyes..might have been anything from dust to bug to diode..

 

[Tunedfrog]

Silly me TNT I missed that part.

 

[WickedFog]

Agree with tntpoof here. It could very well just be some dust that was easily smoked. Drive it for a short jaunt then back, check the ESC temp, and if ok, drive it a bit farther and repeat. If you can get a few trips down and back running hard and it stays cool, likely it's just fine.

Welcome to RCTalk

If you stick around, go introduce yourself. This is a really cool place to hangout, with some great folks.

 

[Doom!]

Welcome aboard, @WickedFog 's advice sounds solid.

 

[9x19]

Welcome to RCT!

 

[Greywolf74]

One of my trucks is an older model Traxxas Stampede 4x4 that is using a Mamba Max Pro (Older Castle ESC, predecessor to the Mamba X). I run it along with a 2400kv 36x74 motor on 3s and 4s. The truck had been on the shelf for about a year after a hard landing that broke a couple of teeth on the spur. After getting the new spur installed and putting the truck back together, I plugged in a battery to test the truck and even though the Mamba Max Pro started up like normal with the expected beeps, smoke also began to start coming out of the side of the ESC. I immediately pulled the plug on the battery.

I'm still not 100% sure what happened, but when I removed the heatsink, I noticed that the thermal paste was VERY dry and crusted. I guess that makes since since I got the ESC 13+ years ago at this point. I cleaned everything as best as I could, used some computer CPU thermal paste, and put the heatsink back on. Surprisingly the ESC seems to work fine.

While I'm thrilled that the ESC still works, I can't help wonder what was smoking? Was it probably just the dry paste? Should I just continue using it until it stops working again or is it risky to keep using it?

Id take WF's advice and see what happens.

Just as a side note, you can improve cooling performance a tad if you use Thermal Grizzly Conductonaut Extreme Liquid Metal Thermal Grease. Just be careful when applying it that none of it spills off the side of the die because unlike traditional thermal paste, Conductonaut is conductive.

 

[Dan B.]

One of my trucks is an older model Traxxas Stampede 4x4 that is using a Mamba Max Pro (Older Castle ESC, predecessor to the Mamba X). I run it along with a 2400kv 36x74 motor on 3s and 4s. The truck had been on the shelf for about a year after a hard landing that broke a couple of teeth on the spur. After getting the new spur installed and putting the truck back together, I plugged in a battery to test the truck and even though the Mamba Max Pro started up like normal with the expected beeps, smoke also began to start coming out of the side of the ESC. I immediately pulled the plug on the battery.

I'm still not 100% sure what happened, but when I removed the heatsink, I noticed that the thermal paste was VERY dry and crusted. I guess that makes since since I got the ESC 13+ years ago at this point. I cleaned everything as best as I could, used some computer CPU thermal paste, and put the heatsink back on. Surprisingly the ESC seems to work fine.

While I'm thrilled that the ESC still works, I can't help wonder what was smoking? Was it probably just the dry paste? Should I just continue using it until it stops working again or is it risky to keep using it?

I’ve never seen one of these oldies! Do they have internal capacitors? If so, maybe that’s what smoked out. Just spitballing.
Welcome to RCT!

 

[Lukedavis]

Welcome to the forum!!!

 

[GotNoRice]

Just as a final followup to this. My initial conclusion that it "still worked" was based on a somewhat low-speed test run using a 2S LiPo, where it did seem to work fine. Days later when I put 4S LiPo in there and hit the throttle pretty hard, it started cogging really weirdly and soon became totally unresponsive. From what I can tell it's totally dead now, although the steering still works. Maybe I can keep it and use it as a BEC now