water tanks

robo24 · Senior Member

water tanks

Possum3 · Guru

In my van I have to Manually change which tank the pump will draw water from - Do you have the same arrangement? Otherwise I have no ideas if the pump is actually working and cavitating. Check manual for FAQ's about pump operation.

Tony Bev · Guru

Hello robo24

A few pictures would be handy

Two full tanks not decanting water into the empty (the one with the pump) tank could mean one of several things

Hose/s from full to empty tank blocked
Hose/s from full to empty tanks going uphill (water will not decanter uphill)
Was caravan level
Are you sure that two tanks are still full, (in a normal situation as you pump water) the water finds the same level in all three tanks
Are there (for whatever reason) valves fitted between the tanks, so that you can turn off a valve, if you only wish to fill one tank
Do you have a pump in each tank, or do you have some sort of switch over arrangement
Has a hose between tanks, been accidentally kinked

A bit more information would be handy, otherwise we will all be guessing in the dark

Hope that it is sorted out, and can you let us know what happened, as it may help others in the future

Edit to say that Possem may have hit the nail on the head, as I was still typing

-- Edited by Tony Bev on Thursday 27th of April 2017 12:20:14 PM

robo24 · Senior Member

Thanks possum3 and tony bev.Looks like i will be spending more time under the van.

macka17 · Guru

Most water tanks have a moulding at bottom on end\s. Round and prominent.

Heat burn or drill holes to suit water connections to tank.
Install (however) and link bases of tanks together.

Just put garden valve between each tank and you can control flow.
Simplest way to go.
Mine filled 1 to 2 with vents above tank tops.
and all drained, interconnected from bottoms.
As said. Up together. Down together.

Ain't gravity great.

Third was Stainless tank for drinking\filtered water only.
Own pump, and tap at sink.

robo24 · Senior Member

All 3 tanks connected top and bottom.

macka17 · Guru

Either ALL empty and you not realising.
or blockage in pump line, outlet from tank to pump.

Maybe a plastic cut out? when installing.
Jayco have a very bad rep for lack of QC.

Dundiggin · Member

I have two 80L tanks connected top and bottom

One pump pulls from both

The front tank always empties first I don't Know why, you would think they would both go down together.

Anyway when the front tank is nearly empty I get under and turn off the bottom tap linking that tank to the back one.

If I do not the pump just starts sucking air, even though there is water in the back tank.

It is important to do this before it starts sucking air or it can get an air lock in the pump line which means putting some water in the front tank to get it going again.

It might sound like a lot of messing around but that's what I have to do.

I have a gauge for each tank so I know when they are getting down

WARNING they stay reading full till about half empty,then start dropping and fast

You may have a similar issue

Happy Trails

KevinC · Senior Member

robo24 wrote:
Hi.I have 3 80lt water tanks.During the Easter break we Went to a nearby spot for a few days.Day 4 and water ceased to pump into van one tank was empty and the pump just sucked air even though 2 more tanks were full and inline.Plus i used plug hole to fit hoses to be accessible at side of van.I have also fitted 19mm breathers to all 3 tanks.I am at a loss as to solve this problem.

Mine does the same. The pump needs to be primed as others have said. You may have to use your imagination to force water back to the pump. You get used to it.

robo24 · Senior Member

Thank you KC and Dundiggin.I have filled all 3 tanks prior to our next trip to Longreach so i have time to play around whilst not on the road.Regards