marathon questions, first cart

[MeatMan]

just got my first cart for $300, think its a 91', r1791 is the manuf code, 65842 is the serial #. but my first question is, it takes off really slow and has no power till it gets going, then it feels like it goes the normal speed. also i have read something about resistor carts, good, bad, ugly??? and any power upgrades? battery cables, clean motor anything? thanks, i'm sure there will be plenty more.....

[JohnnieB]

Sounds like you've got weak batteries.
Motor draws more current while accelerating, lowering battery voltage. As cart approaches cruising speed, current draw tapers off and batteries regain some of their voltage, so cart goes faster.

What is your battery pack voltage?
You want to keep your batteries as fully charged as possible/practical.
Here's a State of Charger chart so you can tell how much charge they have.
(Note: the voltages listed are taken after batteries have rested at at least 12 hours after being charged.)

Some people love resistor carts, some hate them.
My issue with them is that a lot of battery power is wasted as heat when running anything except flat out.
However, they can be converter to a more efficient Electronic Speed Control type drive system.
Here's is a link to a conversion kit.
http://www.cartsunlimited.net/Scotty...rsion_Kit.html

[scottyb]

Originally Posted by MeatMan

just got my first cart for $300, think its a 91', r1791 is the manuf code, 65842 is the serial #. but my first question is, it takes off really slow and has no power till it gets going, then it feels like it goes the normal speed. also i have read something about resistor carts, good, bad, ugly??? and any power upgrades? battery cables, clean motor anything? thanks, i'm sure there will be plenty more.....

Resistor coil carts? Good? Yes, Good 1950s technology which we utilized right through the 90s

Resistor carts draw 100% of the battery pack amperage each time you crack the throttle open. The coils burn off the unwanted amperage. Modern drive systems draw only what is asked for. The result is a much more efficient system.

[MeatMan]

So am I correct in assuming she is a 91 model? And can she be made to go faster without breaking the bank?

[kernal]

Originally Posted by MeatMan

So am I correct in assuming she is a 91 model? And can she be made to go faster without breaking the bank?

This is a 1991 Marathon resister coil cart. The resister coils are in the box between the batteries. If yours has a controller, it would be a black brick looking device, probably mounted vertically in the same place and should have a plastic cover over it. As they came from the factory, either cart should make 12-14 mph on level pavement with the controller cart having much smoother acceleration and longer range per charge. To make either version faster in a safe and reliable manner would require the replacement of the power cables, controller, F/R switch and solenoid before adding performance equipment like lifts, bigger tires, high speed motors or gears etc. The resister cart also requires the throttle modification for solid state. If your batteries aren't in excellent shape and relatively new, figure replacement cost for them also but this is true of any cart.
You didn't define "breaking the bank" but my estimate to bring this cart up to modern specs and therefore ready for performance upgrades is just under 1K.

[MeatMan]

well i worked on her a little today and it is a solid state version. is that good?

[JohnnieB]

Originally Posted by MeatMan

well i worked on her a little today and it is a solid state version. is that good?

More efficient, so longer run-time.
Easier to upgrade. Just go to higher amp controller. (Along with Cables, F/R and solenoid)

[MeatMan]

Would 0/1 gauge/ awg be too much cable? Reason I ask is I have roles of that size cables and ends that are used in my job, and being the boss I kinda get what I need for free.

[JohnnieB]

High strand count welding cable is best. (600+ for 2Ga)
If you have Power distribution cable, it is low stand count and too stiff. (Breaks due to vibration)
Also the insulation may not be suitable for the acid laden air inside the battery compartment of a cart.

Some guys have built their own cable and may chime in. I prefer silver soldered, air tight lugs and to lazy to do it myself, so I bought mine from ScottyB.
http://www.cartsunlimited.net/Batter..._Upgrades.html