EZ Go cart will not drive on ground,possible bad motor?

[Harolds secret weapon]

I replaced the wiper arm mechanism and put on an old solenoid and switch mounted to the board and it worked great on jackstands, but when i put the cart on the ground, it would not move and the resistors were glowing red. A couple of days ago it would only go in reverse before i changed the wiper components, then on jack stands i got it to go forward and reverse. Well, now it won't go either direction, where should i start? ohm out the motor? or resistors? New to this site. Thanks for your help in advance.

[JohnnieB]

Welcome to BGW!

What is the battery pack voltage?
Should be 38.2V when fully charged and ought be fully charged when not actually driving cart.

The only difference in forward and reverse is the direction of current flow through the Armature (in a resistor cart - Stator in other series carts) and that is done by the F/R switch.

Basically, if it runs forward, but not in reverse (or vice versa), the problem is in the F/R switch assembly.

Does it still run in either, or both, directions with rear tires off ground?

[scottyb]

I could be wrong but, every time I hear it runs on jacks but not on the ground, I think it sounds like a power supply problem.

[camaroluvz28]

Yeah and most of the time when it runs in reverse its because its one of the batteries in not in the half speed set-up failing or because its only looking for half the power...

[Harolds secret weapon]

Thank You guys for your replies, batteries are good. between 36-37 Volts.
It won't move in either direction now with it on the ground or on jack stands, but before i put it on the ground, i had it moving in both forward and reverse. I guess probably my first thing i should check out is the continuity through the motor and then check my resistors and see if their good? what do you think?

[bigpoppi]

Could it be a bad wire, or post, just a thought, put it in reverse, and check the connectivity of the wires, jiggle and tap each post.... when I connected my ground lights, figuring which 2 battereis to connect to, somehow forgot to tighten down one I changed my mind on..... made it to the end of my street and it died.... nothing either way, no reverse buzzer, just head lights....turned key on and off, forward to reverse, then all the sudden it worked again... made it to daughters, hours later on the way home, it quits again, did the key thing but no results, lifted seat, checked each post to find the loose one thought 'what an idiot' had the wrench, tightened and off i went... I know you probably have checked but what does it hurt to recheck/tap and jiggle..lol

[Harolds secret weapon]

that's a good idea, i will check it out, besides it never hurts to check again. Something i was wondering, yesterday is when this happened, now when it wouldn't drive on the ground, i was sitting on the seat and smelt smoke, when i lifted the seat, the resistor box was glowing red, is that due to the solenoid not de-energizing when i let off the pedal or do you think that it's something more, which is why i'm wondering maybe the motor?
I guess when i get to work tonite, i will just start ohming things out, but would say there is a good chance that the solenoid could have been bad to begin with, therefore causing me problems when i put a load on it, by putting it on the ground?
I really appreciate your help..thanks again..

[JohnnieB]

Originally Posted by Harolds secret weapon

Thank You guys for your replies, batteries are good. between 36-37 Volts.
It won't move in either direction now with it on the ground or on jack stands, but before i put it on the ground, i had it moving in both forward and reverse. I guess probably my first thing i should check out is the continuity through the motor and then check my resistors and see if their good? what do you think?

Between 36 and 37 volts is NOT good. That is from less than 50% charged to little more than 60% charged.
A fully charged 36V battery pack should read 38.2V, with each individual 6V battery reading 6.37V and all of them within 0.1V of each other.

However, even 36.0V ought to spin the motor when the rear tires are off the ground, so something in addition to low battery pack voltage is wrong.

The first thing I would do is charge the battery pack up to at least 38.0V.

Here is a schematic of a resistor drive cart with high current circuit traced.

Added: Also here is a State of Charge vs Voltage chart.
Note: Voltage reading are taken 12 hours after charger automatically shuts off.

[rib33024]

sounds like batteries,, how old are they?? hook your DVM meter to the pack and put it in forward and step on the go pedal, and tell us what the volts drop to? , make sure none of the coils are touching each other, how many hours do the batteries charge before the charger turns off by it's self?? the motor is the last thing it will be, unless some one turned one of the studs in side the motor,

[Harolds secret weapon]

Thanks Johnnie B, i'll charge the batteries tonight. I think I found out what happened though. My resistor board that the resistors mount to was pretty well shredded and the coils are older than the dinosaurs. So, i'm ordering a new resistor board and found a few resistor wires to replace the one's that burnt up and we'll go from there. Thanks for the schematic and voltage chart too Johnnie B. I'll keep you updated once i get the parts in what happens next.
thanks