1988 36v marathon HOT battery

[Cmartin2001]

Thank you for adding me to the group. im a first time cart owner trying to get my feet wet but im running into problems.

I picked up this 1988 ezgo marathon 36v resistor coil perpindicular driven cart that came from disney world. it appears to be in great shape. when i got it all of the wiring was taken out so i have searched forums and google for schematics to get this thing back in working order. im by no means an electrician or a cart mechanic but i do have a background in industrial maintenance so ive been known to fabricate and troubleshoot from time to time. i did install a 4 inch lift and some 20 inch tires unfortunately i did that before i decided to try my hand at wiring it up.

the first thing i did was test each battery( 8 ) 6v duracell. the previous owner had 6 in the stock location and 2 more under the rear seat. out of the eight batteries 4 were bad at first glance testing at just 2v. i purchased 2 new 6v to get me back up to 36v.

i attempted to charge them all day but i noticed the charger would take off at around 15 amps and after 30 minutes it would drop to 10 amps. and then about 2 hours in the charger would drop out all together. 37v. i could unplug the charger and plug it back in and the process would start over. after 4 or 5 cycles i was charged to just over 38v.

first test drive lasted about 3 minutes. i backed it out of the garage and down the driveway and while i didnt expect 36v to be a speed demon it felt slow. when i turned into my yard(flat grass) it really slowed down so much that i didnt think it was going to make it back to the driveway. and i started to smell something get hot.

the first battery coming from the f/r switch was getting hot. both terminals and the cables. all others were still cool. all of the connections were clean and tight but the cable looked like it had taken some heat before so i removed it and made a new cable out of an old weld lead. this did not help the situation. the new cable got hot as well so i put my meter on each battery while i pushed the pedal and i found the first battery was dropping to 0v while the rest would only drop to about 5 under load.

i removed the battery and wanted to test again but all i had at my disposal was a 12v lawn mower battery. i knew it wouldnt last as long and i was going over the 36v but if the previous owner was running 48 i figured 42 wasnt going to be a problem. i just wanted to get 15-20 minutes of testing done before i continued to throw money into it.

this time the cart felt like it was taking off like a rocket but if i put the pedal to the floor the cart would lose all power. i noticed A1 terminal on the series motor was very lose. and barely holding onto the case of the motor.

against my better judgement i took the back of the motor off and found the brushes were no longer connected to the post. and the other post had the brush wiring wrapped around it.

i had no luck finding a set of brushes locally so i took the brush wiring and crimped a ring lug to it and connected it to the bottom side of the stud. i used a rubber block with a hole drilled in it as my insulator along with 2 rubber washers. i pulled the armature from the rear axle and fit it inside the brushes and then reassembled everything.

during this round of testing the cables and battery terminals got hot again. and a fully charged 12v lawn mower battery lasted less than 60 seconds of flat surface driving.

im positive ive errored in my testing methods and my temporary 12v battery theory but im trying to save project money until i find out if its a major issue.

im just looking for some advice from this experienced crew