85 Marathon, making it better up hills

[hucklburry]

So I bought my first cart, an 85 Ezgo Marathon 36V electric, this past week. I knew 2 batteries were bad, after a short time playing with it, I bought 6 new Crown 205AH batteries for it and installed.

I took it for a total of an 8 mile ride today, it still had life in it when I got back, charger went to 22amps when I plugged it in after the ride.

GPS flat ground I was getting about 14mph, which is fine. Up even the slightest grade she dropped down to a pretty steady 9mph.

I really like the cart, its in nice shape, pics below - well I guess not, as a new member I have to wait 7 days to post pics, so I will share next week. Its a nice teal color with top.

I intend to install 22" tires/rims that I picked up for a good deal, knobbies for deer camp and such. I am assuming I will have to get a budget 4" lift to run them.

I have searched threads on here, I see ScottyB's stuff that would run basically $700.

I cleaned all the existing 6ga wire terminals. I have about 20' of welding cable in my garage and a real nice crimper at work, I can make some nice new cables for it.

Would a later model solid state setup make me happy, say it will go 14mph up hill? I'd like to stay on the cheaper side as I don't use the cart much really, but will be using it at a country club for halloween with the kids (good times!)

I guess my question is, what is the least expensive way to get it to run 14-15mph up hills? My main deer stand is basically 1 mile away, almost all up hill (the return trip should be pretty easy on the cart)

[Rodriguezmf1250]

48v conversion?

[kernal]

I will relate my experience. Maybe it will help you.
For a number if years I owned the 2 carts below. The grey one is a 91 but a resister cart like I assume your 85 is. The blue cart is solid state and at the time had a 400amp speed control. Also a series cart like the Marathon and yours. Both carts were 36v at the time of the picture. Beside the obvious, there was another difference. The Marathon had the standard 1.49KW motor and is probably what you have. The TXT had a 1.87KW motor.

On my test hill (paved) the Marathon would hold 8 mph and the TXT would hold 12mph. Eventually I put the motor from the TXT in the Marathon and then it would also climb that hill at 12mph and would make 17mph on the flat with a driver only (under optimum conditions). Before you jump to the wrong conclusion let me point out that the TXT is a considerably heavier cart. The solid state 400amp control does make a considerable difference. (Not in speed but in torque)

That little .36 bump in KW (.5 HP and maybe an additional 800RPM) livened up that Marathon but it was definitely stressing the electrics. Short trips were OK but a 10-15 mile cruise would heat up the wires, speed board and F/R switch.

At present that TXT will climb that hill at 16mph (about your speed goal). To do it required a 48v conversion, heavy duty F/R switch, a 3 KW motor and 6 very stout CR 190 8v batteries.

You want to put larger tires on your cart which will rob torque and make you even slower uphill.

Soooooo, what to do? Some thoughts FWIW.

1. With a solid state conversion and a new or maybe custom wound motor (together around $1500-2000 with your labor) you may get close to 14MPH up that hill. (On standard 18" tires). Also some nice 4ga or better wires and some beefing up in the F/R switch. Keep in mind that the rest of the cart is still 30 years old.

2. Around here a late model (lets say 2002 or newer) 48v Club Car can be had for ~$3000 with lights, back seat ETC and new or almost new batteries. This cart with a mild lift and 22" inch tires would probably do good for you and be reliable. I only mention Club Car because they have been 48v for years and EZGO didn't start 48v TXT production 'till mid 2010 and these carts are just now coming off lease so hard to find used.

3. Starting in 2008, EZGO started producing the RXV. This looks like and is a standard golf cart but it is 48v and has an AC motor. These carts do DO NOT slow down on hills. Max speed is adjustable by a hand held programmer and can be set as high as 19.6 mph. They will hold this even going up my test hill. They would go faster but are limited by software. Awsome! Around here they can be had for ~$2000 in basic form. No lights, or back seat, short roof, windshield and maybe iffy batteries. BUT, you can lift them and add bigger tires with no electrical mods necessary. They are, however, a different animal and your should research them if this is even a consideration for you.

Wordy, I know, sorry.

If you want to keep your cart, a hotter motor may be the way to go but you should probably lower your expectations. Since you are only going a mile to the deer stand and coasting back those old electronics might tolerate that.

[coosa]

I ran an 84 Marathon as a hunting and farm buggy for 16 years. The frame rusted out and I junked it and bought a 2008 PDS cart. Even on 36 volts, the new cart will run in the high 20s and climb hills with ease. It has a 500 amp controller on it.

My old Marathon had 22" tires on it and Kernal is right that those tires are gonna slow you down even more on a hill. On a really steep hill, mine would slow down to walking speed but it would keep climbing and eventually get you there. My farm is only 700 acres, and its 2 miles from one end to the other. I could cover that distance in maybe 15 minutes with the old cart; might cut it down to 10 with the new one. Not sure what I might do with that extra 5 minutes. :)

If the Marathon hadn't rusted out, I'd still be running it and still be happy with it. If I were you, I'd be satisfied with the one you have as is, considering how you plan to use it. Will it really matter if you get to the deer stand one minute earlier? I'd get the cheapest lift kit I could find, install the new tires, and be happy.

If you are gonna put a lot of money into a cart, I'd get a newer model and work with it. Your present cart uses 1940s technology, and a more modern cart that uses a controller has many advantages over the old resistor carts. That's just my opinion after working with both carts; others may disagree. Good luck with it!

[hucklburry]

All very good info, Thank you, you guys have a nice site here!

I was hoping someone would say for about $250 in used take-off parts I could get worthwhile gains. Seems there is plenty of up-grading here that would leave some stock parts lying around that might work for me.

Thank you