Dema 458 solenoid issue/question....

[Rudy]

My Cat 3535 feeds two Dema 458 solenoids. One solenoid opens to provide flow to the undercarriage flush....and the other one feeds high pressure to my spray arch for washing. They are NEVER programed to be open at the same time.

Here's my issue.....the undercarriage solenoid isn't completely closing until about 1 second after the high pressure wash kicks on. I get a brief "squirt" from the undercarriage nozzles when the high pressure comes on. Then....it completely closes. It never used to do this.

I disassembled, cleaned, blew out....and reassembled the undercarriage solenoid. It's still doing it a little bit...albeit intermittently.

Any ideas what my issue might be?

It doesn't leak when closed. It opens perfectly. It just doesn't appear to close completely until the inlet gets pressurized. What's up?

 

[OurTown]

We had a problem with the same solenoid on our under carriage. It would not close all the way and the under carriage would run sometimes when it was supposed to be off. We disassembled and cleaned but it only worked for a short period of time. We bought a rebuild kit and it worked for a little bit longer. (a few hundred washes maybe?) Then we replaced it with a new one and it has worked for about three years now.