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Fresh Water tank puzzle

Nutinelse2do
Explorer
Explorer
Good Day all,

We are preparing for some extensive dry camping and I wanted to be sure my fresh water tank is full as it seems the last few day trips we ran out of water too quickly. Of course the LED gauge does not function properly.

Here is what I did.

Coach level
Drained fresh water tank from bottom.
Turned hose on with a rate of 1 gallon per minute. ( based on jug and stop watch )
Put extension on hose to go into the fill tube.

Here is the puzzle, in 32 minutes water was flowing out the fill tube which tells me that is somewhere about 28-35 gallons in a 68 gallon tank. The rate of 1 gallon per minute should have taken about an hour.

What could cause the tank not to "fill" up based on my math?
How do you verify the tank is actually full when the gauge is not reading properly?

Looking forward to your replies.
Living Our Dream
MTHRSHP - 2006 KSDP 3912
Cummins 350ISL...Spartan Chassis
ESC POD - 2019 Ford Ranger XLT FX4
Zippy Scoot- 2018 Honda PCX 150 on an Overbilt Lift
Shredder at the Rainbow Bridge - You Will Always Be With Us
16 REPLIES 16

bbeezzz
Explorer
Explorer
For those that can not realign the vent tube, blowing air into to the vent outlet will clear the vent line of accumulating water. I carry a 2 foot clear 1/2 inch hose and place one end over the vent outlet and force out the water by blowing in the other end.

Nutinelse2do
Explorer
Explorer
SOLVED-- Thanks for all the replies and great input.

I traced down the water fill tube and needless to say it had more curves and dips in it than I care to show. I reran the fill tube so it had a single sloping path to tank and BINGO she has been taking water for the last 15 minutes. This has been resolved.. thanks again!!
Living Our Dream
MTHRSHP - 2006 KSDP 3912
Cummins 350ISL...Spartan Chassis
ESC POD - 2019 Ford Ranger XLT FX4
Zippy Scoot- 2018 Honda PCX 150 on an Overbilt Lift
Shredder at the Rainbow Bridge - You Will Always Be With Us

FlatBroke
Explorer II
Explorer II
Snowman9000 wrote:
On our Crossroads Cruiser, the pickup came off the side of the tank near the bottom but leaving the last inch or two in the tank. When the tank is only 6 or 8 inches tall, that's a lot of water that can't be used. The fix was to unscrew the piping elbow fitting and make up a new one that had a pickup tube attached to it. The tube was fitted so it ran down to the bottom of the tank.

Agree with this. And if you happen to be off level a bit it could even makes it worse. There was a bunch left when empty with our first trailer. I took off part of the bottom and put a couple of 2x4s across and under the tank on the opposite side of the pick up tube. Then the water had to go down hill. It got about every drop out after that.

Hitch Hiker
"08" 29.5 FKTG LS

Jetstreamer
Explorer
Explorer
Depending on how your fresh water tank vent line is routed, if there is a low spot in it that would allow water to create a blockage, your tank will seem like it is full prematurely. This happens to me all the time. My solution is to carefully pressure feed water in as I fill the tank until water spurts out of vent line. One has to be diligent though to not overpressurize once the tank fills and possibly damage a tank mounting fixture.
Don't ask me how I know.

24fb_freedom
Explorer
Explorer
I had the same problem on my previous rv, so what I did is carry 2 2x6x12" and drive up my two tires that where on the fill side to put the vent tube at the highest point to get all air out of tank.worked for me, just a thought.

Old-Biscuit
Explorer III
Explorer III
YES.........mfgs like to 'include water heater tank' in Fresh Water Capacity (Totals)

We have 70 gallon tank.......Sticking hose down fill tube and hose on full (50#) it takes roughly 10 mins to fill tank until water is running out overflow tube behind rear tire.
But that is AFTER I shortened fill tube....it was too long and had a big 'U' in it and would sag then blow water back out fill opening.

Fortunately fill tube, vent line are accessible thru removable panel in kitchen....water heater/water pump also.

Hope you can access it...check out how fill tube is run and vent line..if either kinked/sagging can casue issues filling tank
Is it time for your medication or mine?


2007 DODGE 3500 QC SRW 5.9L CTD In-Bed 'quiet gen'
2007 HitchHiker II 32.5 UKTG 2000W Xantex Inverter
US NAVY------USS Decatur DDG31

Snowman9000
Explorer
Explorer
On our Crossroads Cruiser, the pickup came off the side of the tank near the bottom but leaving the last inch or two in the tank. When the tank is only 6 or 8 inches tall, that's a lot of water that can't be used. The fix was to unscrew the piping elbow fitting and make up a new one that had a pickup tube attached to it. The tube was fitted so it ran down to the bottom of the tank.
Currently RV-less but not done yet.

Allworth
Explorer II
Explorer II
My overflow tube comes out of the side of the tank, not the top. Found this little secret when I had the belly open.
Formerly posting as "littleblackdog"
Martha, Allen, & Blackjack
2006 Chevy 3500 D/A LB SRW, RVND 7710
Previously: 2008 Titanium 30E35SA. Currently no trailer due to age & mobility problems. Very sad!
"Real Jeeps have round headlights"

Nutinelse2do
Explorer
Explorer
The filler neck enters at the top.

We don't have a HD close by until we get near Seaside, so might check at that time for the water meter.

After we come off blocks tomorrow, will try to fill some more.

Tinmania, you are correct.. We have a 12 gal Suburban. Guess that makes sense it's only holding 56 gallons instead of the projected 68.
Who knows, they might even include the water lines in that number.

Trackrig, I don't believe there are 2 water tanks. There is only one fillneck, and one input and output from the water tank. Would have to take down the underbelly to verify.

Thanks all. Appreciate the input.

Safe travels

Richard
Living Our Dream
MTHRSHP - 2006 KSDP 3912
Cummins 350ISL...Spartan Chassis
ESC POD - 2019 Ford Ranger XLT FX4
Zippy Scoot- 2018 Honda PCX 150 on an Overbilt Lift
Shredder at the Rainbow Bridge - You Will Always Be With Us

Trackrig
Explorer II
Explorer II
Do you have two water tanks? If so, is the second one filling? By your calculations, you're only taking on half of your water capacity?

Bill
Nodwell RN110 out moose hunting. 4-53 Detroit, Clark 5 spd, 40" wide tracks, 10:00x20 tires, 16,000# capacity, 22,000# weight. You know the mud is getting deep when it's coming in the doors.

BobKrogstie
Explorer
Explorer
Does the fresh water fill neck go into the top of the tank or somewhere down the side of the tank? Manufacturers have been known to do some weird things. Just a SWAG.
Bob and Natalie
2008 Grand Junction 37QSB
2009 Dodge 3500DRW Big Horn 4X2/CC/LB/CTD/4:10/Auto

GMandJM
Explorer
Explorer
Agree w 2PMs. HomeDepot has this Water flow meter for about $16.
G-half can always find a way to do things upside-down, inside-out or backward.
It's his Super Power!

2PM_s
Explorer
Explorer
You can get the $14.00 water meter from Amazon, works very well. Seems to be very accurate.

rockintom
Explorer
Explorer
Agree with above. Maybe try to use something like a 5 or 6 gallon bucket to give you a better flow rating. One thing not to forget, is that when the claim is for a 90 gallon fresh water tank it is actually 80 gallons with 10 gallons of water for the water heater (assuming the W/H is 10 gal capacity). rockin'
Rockintom
'12 Excel Limited GKE 33 ft., trailer named "Charm"
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