How to empty fresh water tank without pump?

There should be a low point valve under the trailer for the tank. Why do you need to empty the tank to replace the pump? Why do you think the pump is not working? Whats it doing?

You should have used the low point drain a number of times before this incident. For instance to drain the fresh water system after sanitation.

Can you hear the pump turning on?

The tank is completely full. So I want to avoid driving down the highway with a full tank. I guess it should be ok. But seeing if I can empty it before for better gas mileage

For the pump. It keeps running. But no water comes out the tap. Any ideas how to debug? I was going to take it to a shop

This not a trailer but a class c. Where would I find this valve. I have looked below but cannot find it. Any ideas what it might look like?

wopachop wrote:
Can you hear the pump turning on?

The pump turns on and runs. But no water comes out

If you can find your water tank it may have a drain on one side of it like this,


Turn the valve so lines up with the pipe and it will drain under the RV.

Or if you can follow the line to the water pump sometime there is a valve there that you open and it lets the water out under the RV.

Every RV I've ever owned had a drain underneath somewhere to drain the fresh water tank. You'll just have to look around for yours or check the manual.
Emptying the tank won't help your fuel mileage one bit. Fuel mileage in an RV is a lot more about aerodynamics than weight. Even if it were about weight you're talking about what 2% of the total weight?
The pump mechanism likely just needs a new valve. They can be rebuilt without removing the motor and all.
If it were mine, and I couldn't find the drain valve, I'd just pinch the pipe between the tank and the pump with vice grips while I was rebuilding the pump.

did a valve somehow get switched so it is trying to pull water in from a remote fill rather than the tank? there has gotta be a drain however.
bumpy

someuser001 wrote:
But seeing if I can empty it before for better gas mileage

let's assume a 40 us gallon tank. About 300 lbs of water

The weight (measured) of my RV is 13750 lbs. But let's round that down to 13000 lbs.

300/13000 = 2.3%

I think you may be hard pressed to measure the difference in mileage.

Derrrrrr, ‘nother turn the key and point the RV in the right direction and ride on ignorance is bliss!