How exactly does this valve work? My water pump started running continuously and I note that hooked up to city water, the tank fills whether the water fill switch is on or not. When I flick the switch, I can hear the relay in the next compartment and the rod in this valve is magnetized. Is that center plunger supposed to drop down? Thanks.
jor
To get by, fill water tank and plug your inlet hose (I lost the plug that came with hose, but picked up a shutoff valve at home center. That will allow you to build Pressure in coach. I documented my fix two years ago in a post, don't remember specifics, but if you search my posts about two years ago you might get done information that could help you out
Thanks, Tim but I tried that. The one way inlet valve operates OK. It seems that the pump is in a loop, pumpingmwater from the tank and right back into it. I think it is that big brass valve but I'm not sure how it works.
jor
Hmmm, past my knowledge
It's called a piloted valve. The solenoid opens a very small valve that allow pressure to build up on the other side of a rubber diaphragm. The diaphragm then opens the main valve. They make them this way so very little power is needed for the solenoid. It's the same type of valve used for sprinklers. If it's stuck open is probably because a little bit of dirt is stuck in the small solenoid valve and keeping it open. You might try tapping on it with solenoid "on" to try to dislodge the clog. Reversing the flow might do it too, but that would be difficult do without tearing into the plumbing. Second idea is to remove the solenoid (there's usually some retainer/nut/clip on top) and unscrew the core out of the valve body. The core is the silver (stainless?) piece. Removing the core will break the seal to the valve so make sure water is off and drained. Carefully remove the core and expect to see a spring with a poppet. Inspect for any debris - it might come loose just removing the core. I don't have specific experience with these particular valves so some variation to the above might be needed.
Do you have MOT after hours number?
Tim,
I'm home so it's not an emergency. We were going to leave tomorrow but now it will have to be after this is fixed. Thanks.
jor
Thanks for that great explanation, John. I smacked it a few times just now with a ball peen hammer (with the switch on) but to no avail. Draining the tank now and tomorrow I'll pull that thing and try your other suggestions.
Mine just slides right off the plunger btw.
jor
Call and get the new valve shipped overnight to you. It is an easy swap. The new valve has a manual bypass that you can turn.
Foretravel or the vendor? Wired the same? I think mine just has a hot and a ground going to the solenoid. Thanks.
jor
Had to cut the power wire temporarily to the valve to get it to finally cool down and drop.
Got turned on by accident in my case and with no water flow through it it got hot and jammed.
Your crimp fittings look like the has happened before?
Never seen crimped stuff on an oem installation.
Bob
I called MOT and they shipped it next day to where I was.
It's a 95 so who knows. Probably been out in the past. One of the crimps is mine. It's the ground for a water pump I put in recently.
jor
Jor,
I took mine out and replumbed a manual ball valve and installed it in the water/electric bay with a high quality pressure regulator. Along with that I removed the crappy in line regulator and check valve that slowed refilling down. It used to take at least an hour to fill the tank, now it is about 10 min for a complete tank if the water pressure is good.
good luck,
That's probably what I should have done. Instead, I took it out this morning and disassembled it. Mine was full of hard water deposits. Check it out. Anyhow, I cleaned it up and reinstalled it. It worked great for a couple of cycles (water from tank, from city, water fill) but then failed again. I ordered a replacement from MOT.
jor
I had the same problem with the valve in my '98 320, caused by a leaking valve. I removed the valve, disassembled it, removed the deposits, polished the corroded valve seat with emery cloth, reassembled and re-installed it. The valve is now working fine. The project took a couple of hours.
Great info. My temporary solution is just that. Glad you showed me whats actually wrong. Cool. And pictures to prove it......
Bob