Fresh Water Pump Problem

by Mike Cunningham

Question: I hope I’m doing this right. I was UN-winterizing my 2006 Winnebago 31C Itasca Spirit. I filled the fresh water tank about 2/3 full. Open all the faucets, both hot and cold, and turned the water pump on. Water starts pouring out from under the motor home about even with the back wheels on the driver’s side, from what I’m sure is the fresh water tank over flow. It appears to be a metal pan with about a 1/2″ pipe in the center of it. I checked all the valves and everything is where they are suppose to be, no by-passes closed. I hooked the water hose to the outside water spigot, and when the pressure is turned on, the water starts pouring out from the same spot. I found a kinked line on the water pump outlet, and fixed that, but it still comes out the fresh water overflow when the pump is turned on, or the shore water is turned on. RV Parts store guy said he thought the pump was bad, but I can’t figure out why water would come out the overflow line if the fresh water tank is less than half full. It also does it when shore water is turned on. Doesn’t make sense to me. Everything in the bathroom and all connection under the bed and pump area are bone dry. The shoreline water spigot is visible in the bathroom cabinet and all looks fine.

When I winterized the motor home, I drained all the lines, and used 30 pounds of air and blew everything out, including the water heater, which also was drained first. I was wondering if anyone had any ideas of what might be happening, or what I’m missing on this? There are no leaks inside, only water coming out the overflow when the pump is turned on, or the shoreline water is turned on, and the fresh water tank is less than half full.

Appreciate any help or thoughts anyone might have.

Thanks a million… Mike

Answer: This is just a guess, but when you blew out the lines you may have created a leak near the overflow tube and that is the water you are mistaking for overflow water. Or during winter one of the lines near the overflow tube may have frozen and caused a leak. It does not make sense that if your fresh water tank is only partially full it would overflow. Just our two cents worth.

Other input welcome.

Also please search our site for other posts about “water pump”.

Comments for Fresh Water Pump Problem

Click here to add your own comments

Jul 24, 2015



I have a 1997 class a Bounder, How do I remove the filter at the fresh water pump? I need to check it before I replace the pump.

Jun 03, 2014

water leaking

by: Smokey Camping

I think from what you are saying here you have a couple of things going on, 1) you need to check your one way valve in the system, it is inline to stop the water from filing and in your case over filling your tank when using a outside water source (ie camp campground water)
2) now if this still does not fix your water issue coming from what you think is a fresh water overfill, you will need to uncover the tank and verify it is not cracked from the winter.

Hope it is just a simple valve for your sake, as the water tank can be a issue. Happy camping

Click here to add your own comments

Return to RV FAQ.