waste tank full cut off stopped working

[The Carpet Cleaning Pro]

Hi. Do you have any idea how the waste tank full cut off works on my Ace Chemspec. Mine has stopped working. The float switch is good as it activates a full indicator light on front of machine but does not cut machine off when tank is full. It used to work OK.

 

[Luky]

Hi. Do you have any idea how the waste tank full cut off works on my Ace Chemspec. Mine has stopped working. The float switch is good as it activates a full indicator light on front of machine but does not cut machine off when tank is full. It used to work OK.

When was the last time you clean it the waste tank. It might be not visible by naked eye, but there might be some gunk around float, another thing, did you inspect, if wire going in , is not cut or otherwise interrupted? Does your float activated light in front when you shut it off manually?
Is your float switch mechanically sound?

 

[Jim Davisson]

I'm with Luky, check out the wiring. If the float switch calls for the indicator light to come on properly, trace the ground wire from the light to the kill engine ground circuit. If I was a betting man I would put my money on the problem being in the ground. With out a picture of the wire connection at the tank I can only assume that the kill circuit daisy chains through the indicator light. Good luck!

 

[Jim Davisson]

The engineer that drew the above diagram didn't lay out the orientation correctly on the relay schematic to determine NO/NC pins and wired together the full hot accessory pin into the NO/NC circuit going to the fuel pump and the waste tank float per the diagram (this arrangement seems suspect to me). I don't believe that is how the relay was wired on the actual machine, I could be wrong. The engine may still even run without the electric fuel pump "assist" should the 87a pin (middle pin) be called for, but if the float switch killed the machine previously I still don't believe that it was wired per the diagram.

 

[Jim Davisson]

@Todd the Cleaner does the schematic look right to you?