How do I know if my motor is going bad?

[gumpbuck]

Below is a quote from my original post about this.
I'm still having a slight speed issue, but it's not all the time. Sometimes, the cart seems to be going as fast as before????

So how do I know when/if my motor is going bad???

Quote:
2002 48V DS series, 6 inch lift, high speed/torque motor, 4 ga cables, HD F&R switch.

So, I used the cart to drag my .5 acre food plot. the drag weighed about 120 lbs. After about 30 minutes, I could hear a high pitch whistle sound coming from under the cart. I could also smell an electrical burning scent. The motor was very hot to the touch. I stopped what I was doing and let things cool down.

Now, days later, the cart seems to run slightly slower than I'm used to. Typically, on a full charge, on flat pavement, with only me in it, the cart will run about 22.5 mph. Now, it seems to struggle to get to 20 to 21. There appears to be no charging issues and no other conditions that I have noticed.

While I know that a 2 mile difference is nothing major, but, what if any damage may I have done to it? What if any fixes/repairs may I need to think about?

Thanks for your imput!

--------------------------------------------------------------------------------

The Meat Wagon Operator!!
2002 CC DS, 6 inch Jakes lift, 700 amp motor/contoler, Mossy Oak camo.

[gumpbuck]

Anybody??? 68 views and no comment?? :-)

[mrgolf]

Have you done a load test on the batteries? The brushes in the motor took a big load, they are likely worn, the electronics in the controller were strained also. You have shown us all that a cart does not work good as a tractor. There is not much to say except to check these things. Be thankful it still runs.

[Sergio]

My bet would also be the stress on the batteries is most likely the cause of the issue.

Testing them under load is probably the best option, but you can also measure them individually near the end of the charge when the pack voltage is above +60v. A cell going bad would prevent the battery from charging as high as the good ones.

[gumpbuck]

Thanks Guys!
As for the batteries. You may know from another post of mine. I've got fresh Crown CR165s in the cart now. They are very early in the break in stage. So I guess I will wait till they have had a chance to settle in to see what happens to my speed. If no improvement, then maybe it will be time to check the brushes....
I really can't complain. A 19 mph cart with plenty of torque for off road is still not a bad thing..... Just no more trackor work...

[jjance]

You know what I always say. If it ain't broke don't fix it. BUT I have had a new battery go bad. While charging I noticed one of the individual cells in a battery was not bubbling like the other three. I measured it with a volt meter and it was .5 volts lower than the other batteries. It was also a Crown battery. They exchanged it w/o question.