Is my motor shot???

I ran my Blackjack 24 earlier today and everything was going fine until I heard it making a funny noise and the speed slowed almost to a crawl. I brought the boat in and checked the battery voltage which was about 3.92-3.93 volts per cell so I know for sure the LVC on the ESC definitely did not activate.

I noticed the collet assembly was a bit warm and felt a bit loose but the most troubling thing is that a very thin wisp of white smoke came out as soon as I removed the canopy. It happened so fast I could not tell where this very thin, barely visible bit of smoke came from.

I don't think this came from the ESC as everything still works but after I tightened the shaft, I put the boat in my bath tub to test it and I noticed the motor will not spin up to full speed. It just seems to run at a low RPM. I'm just wondering if I potentially fried this motor somehow.

I also tried to run the motor outside of the boat without the prop shaft connected. Same thing (low RPM) unless the stock Dynamite ESC has a rev limiter built into it.

However, nor the motor or ESC was very hot when this issue occurred. I could touch each component with my fingers comfortably.

Last I saw, the water cooling was working as I saw water coming out of it.

Just want to make sure I replace the right parts. I'll probably give Horizon a call tomorrow morning and see what they say.

This is tough to diagnose from afar, especially since the motor was not 'hot'. The "smoke" was from something hot, was it steam, oil/grease, burnt plastic? Hard to say. What is the history of the motor, did it ever get real hot? Bearings noisy? Wet?

Typically if the motor shorts out it gets very hot, but really the symptoms you list would point to either the motor or the ESC. I would try a different motor first if you have one because the ESC could show the same motor symptoms.


.

Did you pull out the flex shaft and inspect the teflon liner? Look for burnt spots or anything that may be out of the ordinary. Do you grease the flex often?

Quote:

---

Originally Posted by Tamelesstgr

Did you pull out the flex shaft and inspect the teflon liner? Look for burnt spots or anything that may be out of the ordinary. Do you grease the flex often?

---

Flex and liner look fine from what I can tell. I grease the flex after every run.

Quote:

---

Originally Posted by Fluid

This is tough to diagnose from afar, especially since the motor was not 'hot'. The "smoke" was from something hot, was it steam, oil/grease, burnt plastic? Hard to say. What is the history of the motor, did it ever get real hot? Bearings noisy? Wet?

Typically if the motor shorts out it gets very hot, but really the symptoms you list would point to either the motor or the ESC. I would try a different motor first if you have one because the ESC could show the same motor symptoms.



.

---

The motor would typically get up to around 140-145 degrees after a run. This is a 2000kv motor after all. Bearings seemed smooth, not notchy or gritty. I run this boat on 3S with a Prather B215 prop which has the same specs as the stock plastic prop.

Got off the phone with Horizon earlier and they are sending me a brand new motor at no charge.

The tech had me try a few things over the phone while he listened and we both agreed the motor is shot so they are sending me a new one. Definitely can't beat that for customer service.