1991 ezgo marathon 36v not moving

[pl322833]

Hi everyone, thank you to anyone willing to help. I picked up a 91 ezgo marathon from a guy for 300, he said all it needed was batteries and should fire right up. Of course not the case, bought some new Crown batteries, charged them up and went to start, got nothing. Anyways I replaced the ignition switch, and on a whim after looking through the forums found the solenoids go bad fairly frequently so I ordered a solenoid and replaced that. After replacing the solenoid I hit the accelerator and off it goes, awesome! So I get the kids and load them on the golf cart, hit the accelerator and we shoot out of the garage and it dies after 10 feet, and nothing since. The headlights did work initially but after this episode the headlights don’t work. I’ve looked at diagrams to see if there are any fuses I’m missing but haven’t been able to locate. The turn signals work. I pulled out my tester and currently have 37.2 pack voltage, the solenoid clicks when I hit the accelerator in forward and reverse but still no go. I’m not getting 37.2 across the solenoid. I went to the ignition switch, with the Dvm hooked up I got no voltage, key turned on I got no voltage. With the key off if I turn the fnr switch to either forward or reverse I get full pack voltage at 37.2, if I turn the key on it goes to 0. I took the fnr switch off and the micro switch on the passenger side contact looked to be bent but seemed to be making good contact, I switched out as I had ordered one just in case I had found a switch anywhere. So I’m not sure where to go at this point, I’m wondering if the fnr switch has a short which is why I’m getting voltage with the key off or if their is a controller issue, sorry for the long post but just trying to be informative as possible. I also have tried to trace al my lines as it looks someone else had already been into the cart trying to fix my it to make sure everything is hooked up right and as far as I’ve traced everything seems to be correct, once again thanks for any help!

[Bama Brad]

Welcome to BGW!. Are you charging with a golf cart 36v charger? Can you charge full charge (overnight) and let rest for about 8 hours and post total pack voltage AND each battery voltage?

[pl322833]

Yes charging with a 36v golf cart charger, the shop I had bought the batteries from I spoke with the guy that worked there and didn’t seem too interested to help or work on it, he suggested buying a new cart, I’ll charge overnight tonight, then check the pack voltage tomorrow night as well as each battery, thanks for the welcome!

[pl322833]

Total pack voltage 38.2 after charging overnight last night and just checked they’ve been off since I left this morning, each battery is at 6.37. I found the diagnosis section on carts unlimited and it does look like I’ve got pack voltage to the solenoid, it is clicking, when I push the gas I get full pack voltage to the second large post on the solenoid

[pl322833]

I did also test the pot box and looks like it’s supposed to go to 5k ohms the most I get when to the floor is about 2.53k ohms, does this mean the pot box is bad?

[Bama Brad]

Check wires going to it, but I would think it's bad, but I'm not an expert on those....maybe somone with more knowledge will chime in.

[pggroves]

The pot is adjustable. Touchy for sure, but adjustable nonetheless. But 2.5k should at least move the cart..... Have you tried jacking up rear end and see if wheels turn when depressing accelerator?

Are we talking about a controller cart here? In 91 both resistor and motor controller carts were produced.

The motor control info will help all to assist in troubleshooting potential issues. Motor testing, controller testing, etc.

Good luck!

[pl322833]

I have not jacked the cart up to see if the tires move, it has a controller I’d believe to be original so it should be a Curtis. I do have voltage going to and from the micro switch by the pot box, I checked the wires going to the f/r switch but don’t get any ohms when hitting the accelerator in reverse? Should I be testing for ohms there or just voltage?

[rockfordpi]

Originally Posted by pl322833

Hi everyone, thank you to anyone willing to help. I picked up a 91 ezgo marathon from a guy for 300, he said all it needed was batteries and should fire right up. Of course not the case, bought some new Crown batteries, charged them up and went to start, got nothing. Anyways I replaced the ignition switch, and on a whim after looking through the forums found the solenoids go bad fairly frequently so I ordered a solenoid and replaced that. After replacing the solenoid I hit the accelerator and off it goes, awesome! So I get the kids and load them on the golf cart, hit the accelerator and we shoot out of the garage and it dies after 10 feet, and nothing since. The headlights did work initially but after this episode the headlights don’t work. I’ve looked at diagrams to see if there are any fuses I’m missing but haven’t been able to locate. The turn signals work. I pulled out my tester and currently have 37.2 pack voltage, the solenoid clicks when I hit the accelerator in forward and reverse but still no go. I’m not getting 37.2 across the solenoid. I went to the ignition switch, with the Dvm hooked up I got no voltage, key turned on I got no voltage. With the key off if I turn the fnr switch to either forward or reverse I get full pack voltage at 37.2, if I turn the key on it goes to 0. I took the fnr switch off and the micro switch on the passenger side contact looked to be bent but seemed to be making good contact, I switched out as I had ordered one just in case I had found a switch anywhere. So I’m not sure where to go at this point, I’m wondering if the fnr switch has a short which is why I’m getting voltage with the key off or if their is a controller issue, sorry for the long post but just trying to be informative as possible. I also have tried to trace al my lines as it looks someone else had already been into the cart trying to fix my it to make sure everything is hooked up right and as far as I’ve traced everything seems to be correct, once again thanks for any help!

Get some alligator clips and put you DVM on the input side of the solenoid (side from batteries). Put the seat down, get on the cart, key on and press the pedal and note the voltage to solenoid under load. If you have sufficient voltage there, do the same thing on the output side of Solenoid (to batteries).

I have seen a solenoid click and measure good voltage on the output side until cart is under load and the voltage dropped. The Solenoid had failed internally, but was making enough connection to read good voltage under load.

I know you have a new solenoid, but that principle applies to all your high amp wires and connections. A wire or connection can read proper voltage without a load and then fail under load.

Once I saw a cart doing the same thing. Nearly drove me crazy. No evidence of excessive corrosion on battery terminals. I took all the wires off, cleaned them, put back on and the cart ran.

All this to say, be sure you are getting the proper voltage at each point while the cart is under load. I think someone also mentioned testing with rear wheels off the ground which should also give you some insight as this reduces the load.