What's new
Car Wash Forum

This is a sample guest message. Register a free account today to become a member! Once signed in, you'll be able to participate on this site by adding your own topics and posts, as well as connect with other members through your own private inbox!

Underbody Intermits 'Short Spray'

Waxman

Super Moderator
Side Trac 700.

Every 10 or so washes, my underbody spray will shut off after 2-3 seconds (normal is 30 sec. or once vehicle gets on main treadle switch).

Connections in jct. box off main treadle seem fine.

When the underbody does turn off early, no lights flash 'stop' or 'backup' on gantry, which seems to indicate that the problem is NOT that the stop or backup wiring from main treadle is activating those functions too soon.

I plan to call the factory tomorrow, but does anyone have an idea before I call? Maybe a broken wire somewhere? Relay going bad? HELP!!!!!!!!:):)
 
All else works fine. When the underbody 'short sprays' the car proceeds to the treadle and the wash starts and runs fine.

FYI,

I have a spare underbody switch but I thought it wasn't that because of the way the switch sends its pulse.

Is there any way a worn mercury switch will send an early shutoff pulse? Because when the second tire hits it it shuts off the underbody, in theory.
 
If the second wheel hitting the switch is what shuts the underbody spray off it could be sticking some times i have never had one do that before, but i guess it could. did you talk to the factory or your distributor
 
Yes, that is what I was wondering; is the mercury switch in that pad going bad. But in talking to a couple people, my dist. being one, we concluded that it was not likely the mercury switch.

I called the factory yesterday but they were closed. I am washing cars today and will not get a chance to change the pad out, but I will if the factory has no better ideas.


I washed a detail job in my IBA a few minutes ago and underbody worked as normal.
:o
Thanks!
 
Hmmm. How do I know if it's a mercury or treadle switch?

It's a 'tapeswitch' brand ramped floor switch. Is this not a mercury switch?
 
No a tape switch is not a mercury switch, look at the switch i have seen some switches where they spun the tires on it and the switch went bad. does the second tire turn the underspray off or does it time out after so many sec
 
It appears that the switch sometimes also does not turn the underbody off as it should when the second tire passes over it.

Now I am thinking it IS the tapeswitch...
 
I replaced the switch today and tested it; all seems fine now with underbody operation.

The switch I got is longer than original, so I had to cut off and grind down the anchor bolts for one side of old switch and drill 2 new holes for bigger switch anchors. That and the re-wiring of the switch took a couple hours, but I think the new, bigger switch will lend itself to better operation of the spray because customers sometimes catch the pad only a bit as they enter the bay with the smaller one.

Side benefits to the project; I got a cool, new metal grinding wheel for my buffer that works great and is fun to use! Sparks fly, which I think is cooool!:D

I love these little projects. I've got a regular who is waiting for a call telling him the underbody is fixed. A true clean-freak, after my own heart!:D
 
Waxman,
If you didn't already, you might order another tape switch for when the new one goes out. That way, no re-engineering will be required!

Just a thought!

JPRB
 
I definitely should.

I'd just order the right size this time, so it would fit the new anchor bolts.
 
Yes it is ramped.

Good to know, because they offer the flat edged ones, too.

Tested again this morning; working great!:)
 
wow great info..see this a few times myself lately but i also have a different question. My under car spray on one bay isnt working..i check the plc and the number designated for the treadle switch stays on. Do these get stuck when they fail? It is just a normal flat 5"x17" treadle switch. I can force the under car spray on but doesnt work on normal operation. I unhook wiring and PLC shows it goes off but remains "on" when wired.
 
wow great info..see this a few times myself lately but i also have a different question. My under car spray on one bay isnt working..i check the plc and the number designated for the treadle switch stays on. Do these get stuck when they fail? It is just a normal flat 5"x17" treadle switch. I can force the under car spray on but doesnt work on normal operation. I unhook wiring and PLC shows it goes off but remains "on" when wired.

The switch can stick closed
 
Back
Top