Shuttering

[Atrivett]

I have a club car 2002 and I’ve just replaced the motor. It is a stock version with a little more horsepower. All cables are 4 gauge and It has a new f/r switch,a new OBC, a new solenoid. All batteries are checking 8.4 volts or better after charging. Forgot to say it is a 48 volt. The new motor works great, more speed and it didn’t slow down as bad on the hills. This cart is only used for driving around my neighborhood. From my house around and back is one mile. I drove it around twice and the motor started shuttering and went very slow on the hills. I did have the headlights and the radio on. After the hill it smoothed out and picked up speed. What have I done wrong? Put it back on the charger and the batteries check the same. The voltage meter does not show a big drop after a couple times around the neighborhood. I need some help or I’m driving this thing off the nearest hill.

[mrgolf]

Sounds like you ar getting a quick surface charge on the batteries. The meter will read the volts and that will be good but if you don't get a good deep full charge you will not have the amps to back up that voltage. Make sure you let the batteries charge untell the charger turns off on its own.

[NoleFan4Ever]

Everything you are describing is a voltage lag/drop within a Series cart. I would place my meter on the pack and drive around and see what it reads during the events you describe. It is more so apparent due to it only does it after a distance and then or on hills....

[ThreeCW]

Originally Posted by Atrivett

The new motor works great, more speed and it didn’t slow down as bad on the hills. ... From my house around and back is one mile. I drove it around twice and the motor started shuttering and went very slow on the hills.

As NoleFan4Ever suggested, monitor the voltage of your battery pack (under load) when the motor starts shuttering and see if their is a significant change. If so, repeat the same voltage monitoring process on each individual battery (under load, up the hill and shuttering) and see if you can pinpoint it to a problem in one (or more) of the batteries in the pack.

You mention that this starts after a couple of miles ... also trace (feel) along all of your high amperage wires and check for hot spots (as a result of high resistance) to see if it is a bad cable or a bad connection. Also check motor, controller, Fwd/Rev contactor, solenoid, and circuit breaker temperatures (and anything else inline on your high amperage cables) to see if something is heating up and possibly failing under temperature.

Trouble shooting this problem will be a process of elimination and these are a few places to start the process ... other BGW members may have other suggestion once you check these basics.

[Atrivett]

Ok, guys I have done everything you suggested. After charging, the pack reads 52.4 volts. When driving around it drops to 38 volts going up the hills. Stopping, the volts go back to 48. Two times around my neighborhood the motor starts stuttering on the hills. The meter goes bananas while it is shuddering and then smooths out and voltage goes back up to 48 volts. I have it stopped sitting on my carport. Radio and headlights still on. The meter reads 49.7 volts. I forgot to mention that I changed my charging port on the cart. Does something on this need to be reset? The charger comes on and it charges but seems to me that it is taking a short time for the charger to cut off. The controller is still the stock one. 225 amps. Any other ideas?

[ThreeCW]

38 v is too low. Perhaps a bad battery (or two).

Try load testing each individual battery to see if you can find the battery dropping voltage significantly compared to the others.

[NoleFan4Ever]

Originally Posted by Atrivett

-snip- When driving around it drops to 38 volts going up the hills. Stopping, the volts go back to 48. Two times around my neighborhood the motor starts stuttering on the hills. The meter goes bananas while it is shuddering and then smooths out and voltage goes back up to 48 volts.

That is your battery. Now do the test again and one battery at a time and see if it is one or two batteries or the whole pack. Somewhere around and under 42 volts is where a Series will usually start bucking.

[Atrivett]

Ok guys, how low should an individual battery go when you are driving around?

[NoleFan4Ever]

Battery Percentages.jpg

It is more the comparison with the other batteries in series.

[Fairtax4me]

Originally Posted by Atrivett

Ok guys, how low should an individual battery go when you are driving around?

Depends on terrain and cart setup, but stock configuration club car says a cart should be able to run 3 full laps of an 18 hole golf course. Somewhere in the range of 30-40 miles on flat ground.