1999 Ezgo slow up hills

[Falcon]

My 1999 Ezgo TXT Series cart
Electric 36 V
battery's at full charge = 40.54vdc
with a full charge up hill 37.60vdc
battery after full charge and setting for 12hr.
battery 1 = 6.50vdc
battery 2 =6.74
battery 3 =6.70
battery 4 =6.65
battery 5 =6.74
battery 6 =6.54
This cart is moving real slow up hills.
It's fine on level ground. and it goes up hill fast in reverse .
My question is what can cause it to slow down up hills ?

[rueben68]

I have a 2001 36v Ezgo with brand new Trojans and I have the same thing but I don't think its a problem with the motor or the batteries. I spend a lot of time in Put In Bay and there are a ton of golf carts there and plenty of hills and they all do the samething but if you want to change the motor and you are willing to spend some money try this site. http://www.plumquick.com/

[Falcon]

I guess I should tell you every now and again going up a hill the cart will cut off ( no power ) just like the switch was cut off ! But only for a split second .
And it only happens going up a hill.

[JohnnieB]

Originally Posted by Falcon

My 1999 Ezgo TXT Series cart
Electric 36 V
battery's at full charge = 40.54vdc
with a full charge up hill 37.60vdc
battery after full charge and setting for 12hr.
battery 1 = 6.50vdc
battery 2 =6.74
battery 3 =6.70
battery 4 =6.65
battery 5 =6.74
battery 6 =6.54
This cart is moving real slow up hills.
It's fine on level ground. and it goes up hill fast in reverse .
My question is what can cause it to slow down up hills ?

Something is very wrong with these voltages.
The 'At-Rest" voltage for a fully charged 6V deep cycle battery is only about 6.37V.

How old are the batteries?

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Could also be excessive resistance in the high current loop.
Monitor the pack voltage going up a hill and then monitor between the M- and B+ terminals on controller.
(If you have two voltmeters, monitor both at same time.)

Both voltages should be the same, or close to it.
If not, you've got a bad cable, connector or contact.

[Falcon]

the batteries are 14 months old. they are Trojan T-105 batteries
I did change the battery cables when I replaced the batteries,but only the short cables !
Not the hole cable pack.

JohnnieB you said connector or contact ( are you talking about the cables ? )

Thanks

[scottyb]

A series cart will slow uphill. Even after upgrades they just slow less. That is the nature of the beast. Like any electric motor under load. Take your electric drill for example, it will slow as you push the drill bit into the work. Taller tires? Just put a spade bit on that drill.
Anyway, like Johnny said, losses in power delivery need to be eliminated. That means refreshing the system with new HD cables throughout and higher capacity F&R, contactor and controller. More amperage delivered allows the motor to make more torque which helps uphill particularly. Make sure your tires are properly inflated and eliminating any unnecessary weight can help.

[JohnnieB]

Fourteen month old T-105 batteries ought be in pretty good shape, but the voltage readings are remarkably high.
They are possible, but not likely, unless they are taken too soon (IE: Less than 12 Hours after charger shuts off), or the voltmeter is inaccurate (IE: Weak internal battery).
If possible, recheck your battery voltages with a different voltmeter.

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I probably should have said "Connections" instead of "Connectors".

In a cart with a series wound motor, there are:
a. 13 high current cables.
b. 26 connections. (Cable to stud)
c. 5 sets of contacts. (F/R switch and solenoid)
d. 4 carbon brushes. (Motor)

Total current passes through each of the 48 items listed, so one or more of them could be causing the cart to slow more than usual on hills.

All 13 high current cable need to be 4Ga or heavier.
Any cable or connection that gets hot, is defective.
With hard use, the motor might get too hot to touch, the controller might get mighty warm and the solenoid will be warm, but the rest shouldn't climb much above air the ambient air temp.

Attached is a schematic of a series cart with the high current circuit highlighted. Every cable, connection and contact in red or blue has to be able to pass the same amount of amperage, or you have a bottleneck and poor performance.

[Falcon]

JohnnieB I will double check my reading this weekend and get back to you. And I will check and clean all Connections.After a good charge and a long trip I will check of heat from the control and motor.

And thr R/R switch is about 2 years old now but it real stiff to turn.