Marathon (Controller type) Pot-Box throttle has got me stumped.

[JohnnieB]

Those of you that have read my posts know that I'm at least halfway decent at reading schematics and figuring out how things work.
Well, the schematic of a pot-box Marathon controller cart has got me chasing my tail about how the throttle works.

Nobody I know has one, so I can't eyeball the wiring and figure it out, so I thought I would ask here.

Attached are two schematics, one shows the current path of Throttle circuit with the microswitch on the F/R assembly open and the other with it closed.

I believe the microswitch contacts are open unless the F/R switch is in Reverse.

That puts a fixed resistor in series with a variable resistor (Potentiometer) during Forward operation.
I saw somewhere that the fixed resistor is about 470 Ohms, so let's round it up to 500 Ohms for simplicity.
That would make the throttle range from 500 to 5500 Ohms.

With the microswitch closed, the variable resistor is effectively bypassed, so controller only sees the fixed resistor at the throttle input.
That means the cart only travels at one speed in reverse, rather the having a reduced, but variable speed reverse.

I suspect the schematic is drawn incorrectly and the cart actually has a variable, but reduced, speed reverse.

Would someone that has a controller Marathon with a pot box throttle, or knows for sure if it has a variable speed reverse, please enlighten me.

FWIW: I was so depressed about not being able to figure this out on my own, I sat on the back porch and watched the grass grow while I smoked a Macanudo Crystal.

[Gonkulor]

You got me worried Johnnie, I don't want to imagine you hot boxing Macanudo Crystals

Besides the FNR microswitch, add one more at the pot assy. When the pedal linkage is moved off the stop the switch either opens or closes I'm getting ready for work and trying to speed answer thru this. That's prolly never a good thing but your the man who has the ability to pick out the necessary info.

Here are some pictures of my assy as I was going thru my cart. I was hoping to find some better pictures but maybe these can help.

Best regards
Shon

[Andy4639]

Can't say all of what you say is right but both Marothones I owned they had one speed in reverse. I always unhooked the reverse wires to the F/R switch though after getting them. Cart was so slow it wouldn't back up a small incline.

[JohnnieB]

@ Gonk:
Thanks for the pictures, but can't see if Pot has fixed resistor in series with it, or if MS-4 on F/R switch is a double microswitch.
I knew about the microswitch on the throttle linkage, it's part of the solenoid activation circuit.

@ Andy:
Thanks, that answered my question. Controller Marathons have a one speed reverse, or at least some of them do, and to give them a variable speed reverse, just leave the wire off.

Now I can enjoy my cigars more as I watch the grass grow.

[Andy4639]

As far as I know they have no resisters in line with them that I have ever seen. Stock Marothones do have the double micro switch on the F/R though.

Wiring from key switch down to micro over to controller is all it has. @ wires to controller and 2 to the micro switch on F/R. In the picture the ones to the micro are disconnected.

This is a stock Pot box.

[yurtle]

Is it possible that the series resistor is simply the two outer lugs on the pot, with the wiper actually connected to one of the two outer lugs?

[Gonkulor]

I think this is the resistor JohnnieB speaks of, it's inside the pot box. Yellow Violet Red and Gold. I used to remember the bad boys race our young girls, blah blah, I can't remember it anymore. I can confirm my cart used to be fast in reverse till I readjusted, cleaned, lubed my micros. But recently it started going fast again. I'll have to look at fixing that. I also have 3 micro switches at the FNR.