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Discussion Starter · #1 ·
I just picked up a formerly dead e-gator - after some prodding with a voltage meter, it is now fully working, and the problem turned out to be a combination of broken wires under the hood, corroded battery terminals in the rear, and one battery with an entirely melted away terminal. The meter reads 300 hours. All is now working well except it doesn't have sufficient power to climb the hill in my backyard more than twice on a charge - the batteries are clearly old and tired so that's the first thing to replace.

Rather than spending $1,600 on eight new 6-volt lead acid golf cart batteries (my gator has 8 very old interstate GC2-ECL-UTL batteries in it, and new ones are $200 each at my local Interstate store), I just ordered 4 new 12V 100AH Lithium (LiFePO4) batteries on amazon for $1,200. The e-Gator came with a Lester Summit II charger, which can be easily reprogrammed via their Bluetooth phone app to support LiFePO4 battery charging - this is a $500 charger and having it made the idea of switching to newer battery technology an easier decision.

I also order some more electrical goodies to run 12V devices on the Gator - a 30AMP 48v to 12V converter to add 12V power to the system, a dual usb-C charger for the dashboard, an LED light bar, new LED headlight bulbs and LED taillights. Total cost for all this stuff was about $200 on Amazon.

In addition, I'll wire in a new 48V battery monitor designed for lithium batteries as the built-in power gauge doesn't understand lithium batteries.

On the mechanical side, I need to do a brake job (do any of you have a good source of parts and/or know the part numbers?) and I need to buy or built a canopy. I also have a bit of plastic repair work and cosmetic cleaning and painting work to do. I will also change the fluid in the diff as a preventative measure.

Phase II will probably be to add a head unit and speakers, and also to add a 48VDC to 120VAC inverter so I can plug in line-voltage power tools when needed.

If folks are interested, I can post progress reports and learnings.
 

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There have been a few folks sharing their e-Gator experiences

please consider documenting the upgrade with details and some photos.
I’m curious which Amazon sourced lithium batteries you bought. It seems batteries with the same claimed rated capacity range for $300 to $900 (battle born) are out there. Makes one wonder if there is a difference or just overpaying for more brand recognition.
 
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Discussion Starter · #4 ·
Starting to take a look at the brakes - would love ideas from the group wisdom - at only 300 hours, am I likely to be needing new brake shoes, or should I be looking at adjusting the linkage first? The symptom is poor brake engagement - I have to push really hard to get the brakes to engage to slow the gator...
 

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Suggest pulling the brake pads and assessing the situation versus random guessing.

Caliper can be stuck
Pads worn
Rotors worn
etc...
 

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For reference, my ~2000 eGator stops poorly, too (to my thinking). There are only the drum brakes in the rear. I do have some rear axle parts (brakes are complete, and I have the cables, too) from one I disassmbled.
 

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Discussion Starter · #9 ·
Today the boys were having fun playing around with the gator but they couldn't get the electric dump to work. I verified the problem.

The circuit the gator uses to activate the dump actuator is a bit strange.

It starts with an ancient relay that is triggered by the on/off switch. The relay acts as a safety cutout so the dump circuit is broken unless the Gator's on/off switch is in the on position.

The actual dump circuit entirely flows through the dump bed switch, which is a reversing dpdt momentary switch.

High current power and ground enter the dump switch middle terminals, and are either directly applied or reversed and applied to the lower terminals attached to the dump motor when you press the switch either up or down.

Why is it a bit weird? Its much more normal to run low power through dashboard switches and higher power through relays. The e-gator runs full power through the dump switch. I wonder how often these fry...

Debugging was a matter of testing whether the switch had power (it did) and was correctly either passing or reversing power to the rest of the circuit when pushed (it was). Simple to test with a voltmeter.

That left the relay, which turned out to be stuck in the open position - thus breaking the high currect circuit so it would never work. Directly connecting the higher power wires attached across the switched part of the relay immediately restored dump functionality, but as a side effect eliminated the safety interlock with the gator power switch.

Replacement OEM mechanical relays from john deer are about $150; I ordered a $15 48 volt, 40AMP waterproof modern DC relay from Amazon that should be a perfect substitute. It should take no more than 15 minutes to solder in when it arrives.

Hope this helps anyone having e-gator electric dump problems.
 

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Discussion Starter · #10 ·
I think the Gator is telling me i need to quit screwing around and install its new lithium batteries... The boys we're having a grand old time driving around last night and they heard a loud pop just before the gator died. Not super hard to diagnose!
Automotive tire Wood Gas Auto part Fastener
 

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Discussion Starter · #11 ·
Removed the old batteries, cleaned out the battery tray, and the new batteries fit like a glove. So pretty!
I note there is not room to put 4 more of these batteries in the existing battery tray, so hopefully 48 volts at 100 AMP hours will be enough... In an emergency, maybe 3 more batteries would fit under the bed and one more under the passenger seat, but hopefully it wont come to that...

The new lithium batteries are so much lighter than the lead acid batteries it replacing. I would guess about 500 pounds lighter in total.

It looks like the existing hold downs will also work perfectly, I was thinking I was going to need to fabricate something to hold the batteries down but it looks like that's not going to be needed.

Next step is building new battery cables. I bought some 2 gauge cable and terminals and will hopefully have time to fabricate the new cables tomorrow. The existing cables are 4 gauge...

Green Electrical wiring Wood Gas Technology
 

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Out of curiosity I looked up the original battery weights. Although I couldn’t find the weights of the interstate batteries published, other manufacturers were listed between 60-62 lbs each, so 8 would total just under 500 lbs.

New lithiums are 24.2 lbs each or approximately 100 lbs. weight savings 400 lbs which is very considerable. 👍

is the any concern for what appears to be less energy capacity? I know lithiums can have more useful capacity but even taken this into account it seems there is still some loss of usable capacity. Just asking your thoughts. I think the lithium conversion is still the best way to go.

looking forward to hearing how this works out after some useage time.
 
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Discussion Starter · #13 ·
Yesterday i built new battery cables from two gauge marine grade wire and hooked up the new lithium (LiFePO4) batteries. Wow what a difference - the gator now can spin the back tires when starting from scratch or going up a hill. Really fun!

I also put in a new master switch to completely disconnect the battery pack when the gator isnt being used. It seemed strange to me the computer was always fired up, even when the ignition was turned off. Now when it is turned off, it is completely turned off.

I also swapped out the stock incandescent headlight bulbs for LED's - this required some small modifications to the old bulb holders and the new bulbs but was almost plug and play. So much brighter and better color temperature, plus less power use.

I did some more debugging of the lift gate circuit and found some mistaken prior wiring modifications by one or more previous owners. I suspect they found loose connections under the hood and plugged them in to random places - no wonder it didn't work - they had the lift gate safety circuit connected to itself and to one leg of an unused old light switch. After fixing the connections, the new lift bed relay is now wired in and the lift bed is fully working as expected.

Lastly i installed a trailer hitch - easy bolt on upgrade to the back of the gator.

What's left? Some minor body repairs, brake diagnosis, adding a light bar, plugging in a new reverse alarm, and adding a 12V power converter so i can add some more automotive electrical toys.

Green Circuit component Motor vehicle Hardware programmer Electrical wiring

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Thanks for the update. Sounds like you're making great progress.
 

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Discussion Starter · #15 ·
Had some time yesterday to do more wiring.

First I finalized getting the dump bed circuit back to the original factory wiring path. I have to say I don't like it at all. I had assumed that the factory safety interlock only allowed the bed to work when the ignition key was on. What I learned after hooking things up was it's the exact opposite of this - the safety interlock is only enabled when the ignition key is off. That stinks. I want to be able to dump while I'm driving. So I will probably make up a bypass wire to complete the safety interlock circuit, but also make it easy to return to factory settings if I ever sell the gator. The bypass wire will basically short out the two bottom terminals on the ignition switch, and permanently connect the black / black and yellow wires coming from the dump harness.

This is a picture of the modern 48 vdc relay I installed to replace the factory relay. It cost about $10 on Amazon versus around $150 for the John Deere part.

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Discussion Starter · #16 ·
I also installed a 48 volt DC to 12 volt DC down converter. This will allow me to run standard automotive accessories that run off 12 volt DC power. It fits perfectly under the Gator's Hood right above the front driver side wheel well.

The 48 volt side of the down converter is connected to the negative battery terminal and from the switched on side of the positive battery cutoff switch I talked about above. There is a triggering circuit built in to the down converter and I connected that to the orange wire coming out of the ignition switch on the gator, which is connected to 48 volts DC when the switch is turned on. This way the converter is only turned on when the Gators ignition key is turned on.

I installed a small automotive fuse panel onto the front firewall of the gator above the accelerator pedal. The fuse panel I purchased has six slots and is a bonus that has LED lights that illuminate if any of the fuses burn out.

The first 12 volt device I will install, hopefully tonight, will be a combination dual usb-c high power charger and voltage mirror which I will mount in the dashboard below the gator's built in hour and battery level meter.

I'm thinking about installing a a waterproof automotive or boat head unit and speakers, and perhaps a street legal lighting kit too. All of these things are 12 volt systems...

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Discussion Starter · #17 ·
Last post for today.

Recall that I installed a battery cut off switch on the driver side of the gator. This basically interrupts the power flow from the positive 48V battery terminal headed into the gators computer so I can completely shut the gator off.

What I was fooling around with last night was what to do with the positive lead from the Gator charging port. Initially I hooked it up to the switched on side of my interrupt switch, but that seems silly to me because it means I have to turn the master power switch on to charge the gator. So last night I changed the wiring so the postive charging lead connects directly to the battery.

I need to look at the electrical schematics to make sure there are no hidden downsides of connecting things this way, but it makes more sense to me if the gator can charge regardless of whether its new master power switch is on or off.

I also don't really understand the purpose of the factory cutout circuit that doesn't allow power to the gator when the charger is plugged in. Is it as simple as they don't want you to be a dummy and drive away with the charger plugged in? Or are they worried about something else?

Anyway I need to do some noodling on the factory circuit diagram and then make a final decision about whether I leave the charging circuit landing on the switched or the unswitched side of the positive 48v battery circuit...
 
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