What does a Speed controller varistor do?
 

I bought a '94 marathon with a blown controller (blow a hole in the bottom). While taken the controller out of my other '94 I noticed this yellow disk. It was not on the blown controller one.

What does this do?

http://i78.photobucket.com/albums/j9...6/IMAG0255.jpg

I put in the controller on the yellow disk, and the buggie runs. However if you push the peddle all the way down, it stalls.

Thanks...

Re: What does a Speed controller varistor do?
 

The Varister isn't what's disabling your cart, sounds more like the pot box is going out of range. What readings are you getting from the PB-6 box?

Re: What does a Speed controller varistor do?
 

Rabbit what does the varister do?

Also where do I take readings from for the PB-6?

Re: What does a Speed controller varistor do?
 

The Varister shunts inrush voltage away from the controller to protect the internal components. If you have a resistor on the solenoid, you don't need the Varister.

pull the black and white spade connectors from the #2 and #3 pins on the top of the controller and take the resistance readings from them.

Re: What does a Speed controller varistor do?
 

The buggie "had" a varister on it because it had the parts that connect to the controller but the yellow ball wa missing. Maybe that is why the controller blew.

I will check the resistance tomorrow, thank you.
I know Scottyb has been over this with me before, but I just can't get it through my head. I don't understand the POTs and the microswitch.

Re: What does a Speed controller varistor do?
 

it's possible that that was the cause, but from experience, I have seen carts run for years without having the Varister installed on it.... keep in mind on those old Marathons, the controller is really exposed to the road elements and it is rough on them.....

Re: What does a Speed controller varistor do?
 

I got a reading of 47.
What is it supposed to read?

Re: What does a Speed controller varistor do?
 

So did I do this wrong?

help....

Re: What does a Speed controller varistor do?
 

I have a spare POTs, should I just swap them and see what happens?

Re: What does a Speed controller varistor do?
 

sorry had a few busy days.... the Pot should read 0 at pedal rest and roughly 5k ohms at full pedal down.