Melex Cart Help

[Qtband]

I bought this cart today and the first thing I noticed is...aren't the + and - reversed? Look at the picture. Shouldn't + be RED? I havent tried it yet because I need to install new batteries. The owner said it was "highly geared". Maybe because it is wired backwards???

[golfcartg]

When the previous owner mentioned that the cart is highly geared, they likely meant that the gearing in the transaxle has been modified. High gearing typically refers to a lower gear ratio, which can make the cart go faster on flat ground but might reduce torque, making it harder to climb hills or carry heavy loads. This kind of modification is done mechanically within the transaxle, altering the relationship between the motor’s rotations and the wheels rotations. To confirm this, you could simply ask the old owner if they saved the original gears.

I see what you’re pointing out though. If the positive (+) and negative (-) terminals were indeed reversed, it could cause quite a bit of trouble. In a scenario where the cables were truly swapped, trying to run the cart would likely result in instant electrical damage. Controllers and other electronic components are designed to work with the correct polarity, and reversing this could cause short circuits or even permanent damage to the electronics.

As for making it "highly geared" by swapping the polarity. Polarity affects the direction of the electric current, not the mechanical gearing. Changing the polarity wouldn't alter the gear ratios or make the cart run faster or slower in any beneficial way. In reality, what’s probably happening is that the cable you see isn't actually reversed. Looks like the cable has overspray from the paint job making it look different.

If you need new batteries, I recommend checking out Sam's Club or Costco for some affordable options. These stores often have good deals on lead acid deep cycle batteries, which are what you’ll need for your golf cart

[Qtband]

So how do I verify the correct polarity?

[golfcartg]

Even though the batteries in your cart are at the end of their life, you can still try charging them with your charger. If they don't accept a charge sufficient to power on the cart, you can attempt to individually charge each battery using an automotive charger. To do this, first take photos of the wiring layout and label each connection to ensure you can easily reconnect them later. Disconnect each battery, and charge them thoroughly one by one with the automotive charger. (while you have the batteries disconnected and after they are charged, run an individual load test on each battery to check their health, click that link for more info on that).

Once you've got some charge in the batteries, reconnect them according to your photos and labels and we can run some tests using a volt-ohm meter (VOM) to check for voltage and where it goes. This process involves measuring the voltage in the overall system to identify where its going and if there are any issues like reverse polarity somewhere.

[Qtband]

Even though the batteries in your cart are at the end of their life, you can still try charging them with your charger. If they don't accept a charge sufficient to power on the cart, you can attempt to individually charge each battery using an automotive charger. To do this, first take photos of the wiring layout and label each connection to ensure you can easily reconnect them later. Disconnect each battery, and charge them thoroughly one by one with the automotive charger. (while you have the batteries disconnected and after they are charged, run an individual load test on each battery to check their health, click that link for more info on that).

Once you've got some charge in the batteries, reconnect them according to your photos and labels and we can run some tests using a volt-ohm meter (VOM) to check for voltage and where it goes. This process involves measuring the voltage in the overall system to identify where its going and if there are any issues like reverse polarity somewhere.

I have 6 new batteries going in tomorrow morning.

[golfcartg]

I have 6 new batteries going in tomorrow morning.

Here are some quick tips.

Document the Setup: Take detailed photos and label all connections before removing old batteries for accurate reassembly.

Inspect the Battery Compartment: With the old batteries out, note any signs of damage or corrosion in the battery compartment.

Secure Connections: When connecting each new battery, make all connections tight but avoid overtightening to prevent damage to the terminals.

Main Negative Last: Always connect the main negative cable last to minimize the risk of sparks.

Check for Heat: Carefully feel around the batteries and connections for any signs of excessive heat during and after installation, as this could indicate a improper/poor connection.

Safety First: Avoid parking the cart inside or near structures until you are confident that the wiring is correct and there are no issues, as faulty connections could pose a fire hazard.

Check Water Levels: Lead acid batterys require regular maintenance, check the water levels in each battery, and top them up with distilled water as needed. Batteries consume the most water under load like climbing hills or after an intense charging session.

Cleaning Batteries: Periodically clean the batteries and terminals with a mixture of baking soda and water (1 cup of baking soda mixed with 1 gallon of water) to neutralize acid and remove corrosion. Use a brush to apply the mixture, then carefully rinse with water and dry with a clean cloth.

Preventing Corrosion: After cleaning the batteries and making sure they are dry, apply a thin layer of dielectric grease or petroleum jelly to the terminals to prevent corrosion.

Lifetime: Expect to get 5 years out of your new batteries, without regular upkeep, it will be significantly less.

Off Season Storage: For long term or off season storage, fully charge the batteries and disconnect them from the cart starting with the main pack negative. Store the cart or batteries in a room temperature dry place, and check their charge level monthly, recharging if necessary or hooking them to a battery tender.