Water pump cavitates

[Big Jim]

I have had this problem with my water pump. Usually on Saturday night, my fresh tank acts as if it has been run dry. The pump starts to suck air, cavitate, sputtering out the faucets whe opened.

The fresh has water in it! I know it has water in it, there is NO way I am using 100 gallons in less than 2 days, I crawled underneath to check them.
My unit is dead level.
My pump is new, warranty replacement.
What I did this last time was to up the nose so it will drain to the rear tank.
What is going on?????

[Terry]

If you fill up the tank again does it start working fine? I am wondering if the siphon tube is not all the way down to the bottom of the tank.

[Big Jim]

I does come out of it if I add water, but on Friday night I fill my tanks at the campground, FULL, unti it comes out the overflows.
It's puking as I level it.
The pump draws from the side if the tank, near the bottom, at the rear of the tank, there is a fitting welded to the tank.
It gets really noisy, hammering the water lines, sounds like the pump is a jackhammer!

[Zombied]

Check the suction fittings. Maybe it's drawing in air. Is a vent open somewhere that it shouldn't be? Has the pump been primed and vented? I'd check that stuff first.

[Big Jim]

It does it when the tanks get "low."
It says 1/3 on the meter, but still should have 33 gallon on 100 g capaciy, correct?
I let the tanks out on my way home, about 10 minutes, then, drained in my drive for another 45 minutes.

[David472]

Originally Posted by tafische

If you fill up the tank again does it start working fine? I am wondering if the siphon tube is not all the way down to the bottom of the tank.

I agree with tafische,
the supply line pick-up must be in the wrong spot of the FW tank.
I would have it checked under warranty, since by your signature, it's a 2011.

[Big Jim]

I called my dealer talked to a service tech, he said, that sometimes the inlet valve that you use to winterize the system may leak.
Intead of letting it sit at the shop I did it myself, bought some new PEX valves and installed them hope this is it!!!
Yes, I know my warranty would have covered this, if my fix doesn't do it, it will go back, they can deal with it.

[Murphie]

I just read another post where trailers were loosing water out their over flow while they were driving. Difficult to analyze when your driving the trailer. I guess with the water sloshing around while driving creates the chance for it to escape. I have noticed a lot of posts lately where people couldn't account for loss of water. I wonder if this overflow tube is a recent addition to the Jayco design. I'm aware there are other pump related problems as well. I was surprised to find that there is at least a dozen feet from my fw tank to the pump. I have not experienced any problems but am going to keep a close eye on my water levels.

[RVhiker]

On my new trailer, the water strainer attached to the inlet side of the pump was missing an "O" ring, and sucking air.

[Big Jim]

I think that my tanks were low. I have been having problems with my tanks puking water out the overflows after I fill them.
I installed some valves on my overflows to close them off as I am driving to my site.
I'll see how this works...