Lou asks: I have an E-Z-GO Marathon 36-volt electric golf cart. Batteries are fully charged and in good condition. Step on the pedal and it takes off quickly; goes just like new for about 100 yds., then loses power and limps back. I believe I can replicate the issue in order to drain the batteries, then charge it and start again. Any help would be much appreciated.
Guru: Lou, the issue you are having can be caused by a battery not holding its charge or a compromised battery cable connection. First, check the battery cables and their connection at the batteries. If all seem to be good, move on to testing the batteries. Second, run the car until it starts the issue. Jack up the rear of the car. Use a voltmeter, set on DCV or load tester to check each battery. If you are using a voltmeter you may have to press the accelerator pedal and engage the solenoid to see the volt drop under load. You are looking for the one that drops to a lower voltage than the other batteries. The one that drops lower than the others would be the cause.
FOLLOW-UP
Lou: Ray, Thank you for the information you sent. I took your advice and started with the batteries and found two out of the six would only charge up to 5.5 volts, whereas the other four charged up to 6.5 volts.
I replaced these two batteries along with a new diode and resistor on the solenoid and the cart came back to life. Thanks again for the excellent diagnostics.
QUICK TIP
Hi Ray, I have this guy looking for some gears, but there are no labels on the axle housing. How can I tell if he has the Kawasaki or Graziano?
Guru: Andrew, the way to tell the Graziano from the Kawasaki electric rear differentials is the bolts that hold the case together. The Graziano uses a bolt with a 12mm head. The Kawasaki uses a bolt with a 10mm head.
Email your questions to Ray at guru@golfcarnews.com.
