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Topic: water tank (Read 585 times) previous topic - next topic

water tank

trying to type fast, expect tp loose my connection. I am a Dixie Fire evacuee, in a campground without a lot of tools.  My water pump isn't pumping water, however when on it creates enough vacuum to colapse the hose towards the water tank. I blew some air thru the hose leading to the tank, and with the fill valve open, I hear bubbles and air.  City water provides proper pressure at sink.  Is there a check valve and or tank air relief valve somewhere?  thanks hope this makes it out

Re: water tank

Reply #1 –
Open the valves att the tank. when water dumps on the ground, close them one by one  and leave the dump valve closed ,until water stops hitting the ground. You must have the tank valve shut off .now and need to open it. 

Re: water tank

Reply #2 –
did just that, several times

Re: water tank

Reply #3 –
Is this a new  event?

Re: water tank

Reply #4 –
Turn the fill valve off.
2001 4010 U320 build #5865 "Bluto-d-Bus" since 09/18
2006 Honda Element ESP Toad
Full timing since 2016 in Western MT
Copilot: Sitka
1975 GMC 260 Avion: sold

Re: water tank

Reply #5 –
all valves are off

Re: water tank

Reply #6 –
every thing was ok, started happening slowly, sure seems like an air vent valve of some sort

Re: water tank

Reply #7 –
Quote from: Jane and Gerry –
every thing was ok, started happening slowly, sure seems like an air vent valve of some sort

Depending on year of coach, look for the fresh water overflow tubing.  Where it routes will depend on year, but it's possible something clogged it.  Would think that might act as the air vent on the tank.
Learn every day, but especially from the experiences of others. It's cheaper!  - John C. Bogle

2000 U320 36' non-slide / WildEBeest Rescue
2003 U320

Re: water tank

Reply #8 –
Please tell us what year and model coach you have.  There is no "one answer fits all".
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020

Re: water tank

Reply #9 –
Sorry dodn't realize year wasnt on here anymore.  1987 36 ft  Grand Villa ORED

Re: water tank

Reply #10 –
The vent is under the hood , center of tank.  The pump will  pump water until  the plugged vent stops it . But, if you have pushed air into the tank from the pump, there is not an air lock .  The symptoms indicate a plugged inlet    in the tank. 

 I'll look fri at mine .

Re: water tank

Reply #11 –
 At the tank, I only have 2 valves. One dumps and the other fills from city water.  Both of these are on the same tank fitting. The tank draw fitting has no valve.  The draw line goes directly to the pump.

Re: water tank

Reply #12 –
If you overfill your tank with the hose connection, the overfill will exit somewhere. This "somewhere" is overflow protection and the air vent. Every fresh water tank has to have a functioning vent. Without one your tank can be damaged by excess water pressure or a vacuum.
Nitehawk,  Demolition Lady, & our NEW master, Zippy the speeding BB cat.
1989 Grand Villa 36' ORED
Oshkosh chassis, 8.2 DD V8
2006 Saturn Vue AWD

Re: water tank

Reply #13 –
If the water pump is collapsing the line from the water tank then it is not venting properly. If that is the case you should see when you open the tank drain that at some point it stops draining water still in tank or starts burping like the new gas cans will. If it drains normally out of drain valve I would suspect a blockage of some sort between tank and pump. Just my guess.
2008 Nimbus 342
Build# 6464
ISM 500
Allison 4000 w/retarder
2021 Jeep Grand Cherokee

Re: water tank

Reply #14 –
Also. If the tank vent was blocked you would not be able to fill your tank or even worse if it's not venting the pressure would build to a point that something gives. A fitting, a connection or worse the tank itself. If after some checking you suspect the vent. I would physically find it. Me. I would NOT force water into an unvented tank.
2008 Nimbus 342
Build# 6464
ISM 500
Allison 4000 w/retarder
2021 Jeep Grand Cherokee