Water Pump Won't Pump with 1/3 Full Tank

[Steve507]

Thanks Geoff.

I'm holding out hope that they would not be so stupid as to put the feeder line 1/3 of the way above the tank bottom...

This may be helpful. I found that one of the hose connections underneath the counter to the right of the kitchen sink in my 2018 GD 2600 RB became loose due to vibration from traveling to Caba San Lucas and back again to the Sequim, WA. When this happened, the water exiting the bathroom sink/ shower, and/or kitchen faucet was very, very weak. Go to the place in your unit where you would add antifreeze for the winter and make sure that all of those connections are tight. If the system is able to draw in any air due to a loose connection your water pressure from the freshwater water tank will be very poor. Hopefully, this may be helpful.

Steve Falcone

[Steve507]

This may be helpful. I found that one of the hose connections underneath the counter to the right of the kitchen sink in my 2018 GD 2600 RB became loose due to vibration from traveling to Caba San Lucas and back again to the Sequim, WA. When this happened, the water exiting the bathroom sink/ shower, and/or kitchen faucet was very, very weak. Go to the place in your unit where you would add antifreeze for the winter and make sure that all of those connections are tight. If the system is able to draw in any air due to a loose connection your water pressure from the freshwater water tank will be very poor. Hopefully, this may be helpful.

Steve Falcone

[T Alan B]

We have a 2019 29RS with the exact same problem. I think it starts happening when the fresh water tank is about 1/4 filled based on how much comes out when I drain the tank. Purchased a water pump (SHURflo 12v 3.0 GPM Revolution RV Water Pump # 4008-101-A65-Same as original equipment) but decided not to install it at this time because I'm not convinced it will solve the problem. Also haven't found any leaks. It starts happening when the pump keeps running after the faucet is turned off and then sounds like its sucking air. I'm hoping there is a fix someone may have.

Thank You,

TB

[Boom 'r Bust]

My money is on a small air leak in the suction line. I would look first at the screw-on connection at the inlet at the pump.

Thanks Champ. I hope you are right. By replacing the pump and filter basket, I will eliminate the screw on connections as the problem. Unless of course I find one of those is cracked...

[Boom 'r Bust]

This may be helpful. I found that one of the hose connections underneath the counter to the right of the kitchen sink in my 2018 GD 2600 RB became loose due to vibration from traveling to Caba San Lucas and back again to the Sequim, WA. When this happened, the water exiting the bathroom sink/ shower, and/or kitchen faucet was very, very weak. Go to the place in your unit where you would add antifreeze for the winter and make sure that all of those connections are tight. If the system is able to draw in any air due to a loose connection your water pressure from the freshwater water tank will be very poor. Hopefully, this may be helpful.

Steve Falcone

Thanks for your input Steve. I'm glad you were able to find the water pressure problem in your rig.

The water pressure in ours is good when the tank is more than 1/3 full. I would think an air leak outside of the FW intake line would always give me poor pressure. But what the heck do I know?

[Boom 'r Bust]

We have a 2019 29RS with the exact same problem. I think it starts happening when the fresh water tank is about 1/4 filled based on how much comes out when I drain the tank. Purchased a water pump (SHURflo 12v 3.0 GPM Revolution RV Water Pump # 4008-101-A65-Same as original equipment) but decided not to install it at this time because I'm not convinced it will solve the problem. Also haven't found any leaks. It starts happening when the pump keeps running after the faucet is turned off and then sounds like its sucking air. I'm hoping there is a fix someone may have.

Thank You,

TB

Sorry you have the same issue TB... But oddly comforting to know I'm not the only one...

In June, on our next trip, I will replace the water pump and filter basket to see if that fixes my problem. I'll post the results on this thread. As a side note, I'll be using the same water pump as you.

Stay tuned!

[lmlayfield]

I’m having the same problem too with my Momentum 21G.

[Boom 'r Bust]

I’m having the same problem too with my Momentum 21G.

Hopefully replacing the pump fixes the issue and people reading this will have a proven solution. Thanks for your input...

[woundedknee]

Imlayfield, I have the same problem with my 2022 Momentum 21G. The pump won't start picking up unless there is at least 9 gallons in the tank as measured with a flow meter. Once the pump starts sucking air, I can open the dump valve and there's my 9 gallons. All out of reach of wherever the pump pickup is in the tank.

Dave

[lmlayfield]

Thanks for sharing! Has Grand Design taken any warranty position with your problem?