Help w/ water pumping issue...

[solarbri]

So...
This past December, as I prepared my sailboat in Mexico for our annual winter sail, I needed a new water pump. Quickest and easiest fix was to “borrow” the Shurflo pump I had in my OutfitterMfg. truck camper. Perfect fix.
Upon returning to the camper, I installed a new pump. Unfortunately, it didn’t work right. Only pumping a bit of water, but lots of air. Thinking it was a defective pump, I ordered another one once back in the U.S. same deal.
What could have possibly happened to my camper plumbing over the course of a winter parked in Mex. to make this happen. It’s kind of a big job to lower the floor out of the camper just to look around, so I’m asking for any ideas as to why this happened here to the collective.
If it were cracked tubing allowing air into the pump, there would be a leak. There is no leak. I’m pretty damned mechanical, and this mystery has me stumped.
Thanks for any help!
-Waterless Brian

[olfarmer]

Glad you got it figured out!

[solarbri]

Ok. It was a fricken old guy moment.
After dropping the floor twice, changing the pump 3 times, redoing the plumbing in the basement, it turns out, I wasn’t tightening down the hose from the tank to the pump connection tight enough.
Where’s the **** headslap emoji. ???????

[MEXICOWANDERER]

So you can siphon at various places ans get water?

I've seen inside hose liners peel loose. At various suction vacuum they will plug a pipe or remain open. Same for domestic water inlets beyond the pump. You don't have any kind of pressure limiter after the pump? I've had to disconnect the SUCTION side of a pump and blow air backward into a tank to diagnose a few screw-loose problems. Must hear tank boil with air bubbles. Assume nothing. Test 🙂

[solarbri]

wa8yxm wrote:
On the inlet side of the pump ia (normally) a "Strainer" and it can be opened for cleaning and then misaligned when you close it allowing pump to suck air.

Thanks. Good thinking, but there is no strainer. No filter. No anti freeze hook up.
The search continueth...

[wa8yxm]

On the inlet side of the pump ia (normally) a "Strainer" and it can be opened for cleaning and then misaligned when you close it allowing pump to suck air.

[solarbri]

philh wrote:
was water left in the fresh water tank for an extended period of time? Have you tried blowing on the line into the tank?

do you have sufficient voltage to drive the pump?

I’ve put my mouth on the line coming from the tank, and I can suck water pretty easily.
I’m about ready to go drop the lower floor again, and replace the water line with pex, after a THOROUGH investigation.

[philh]

was water left in the fresh water tank for an extended period of time? Have you tried blowing on the line into the tank?

do you have sufficient voltage to drive the pump?

[midnightsadie]

mine had a cracked filter housing sucking air. id there a antifreeze line valve left open. when you find it, it,ll be one of those I must getting old things. good luck.

[Acampingwewillg]

When I was having Pump issues(leaking), I got very tired of getting down on the floor and trying to squeeze my way under the bath sink into the flooring to work in such a tight area. Simple solution for me was to get some like size tubing and move the pump into a much more accessible place....I was probably lucky that it proved to be a pretty easy move but I'm sure others experience will differ.

[solarbri]

pianotuna wrote:
feed line to pump may be leaking. Replace with Pex.

Cold this winter may have frozen the line and cracked it.

I’ll look into it. But, the camper was parked in Mexico through the winter. No freezing pipes.

[pianotuna]

feed line to pump may be leaking. Replace with Pex.

Cold this winter may have frozen the line and cracked it.

[dougrainer]

Your feed line from the Fresh tank to the pump has a open. It is allowing air to be drawn in along with water. It can be a loose clamp. It can be a Pick up tube that has fallen down in the tank. Some RV's use a pick up tube like a gasoline tank sending unit in cars. The most common cause of this is IF you have a winter bypass valve kit, that valve is open or partially open. QUICKEST way to confirm your type problem and NOT waste time swapping and buying new pumps:B , is to take a 1 to 3 gallon water container and run a short hose from it to the input of the pump. THAT will tell you if you have a defective pump and confirm it is the FEED from the tank. Also, another common cause of this type problem is the input filter connected to the pump. IF NOT winterized(drained) it will crack and usually not that visible. It will NOT leak water when attempting to draw water, but will allow that air to be sucked. Doug

[solarbri]

3 tons wrote:
Its hard to say, but maybe you can remove the pump and mock it up say drawing from a water bucket to see if the pump is working properly...

I too share your mechanical inclinations but find that this is more of a burden than a blessing because a black cloud of recurring troubles seems to perpetually hang over me :o- lol!!

Lol. I hear you.
Well, I tried two brand new pumps, and then last night, I borrowed my buddies pump out of his camper, and it was the same result. I can’t imagine three pumps are all having problems. It HAS to be in the plumbing somewhere.
I had contacted OutfitterMfg. and for $120 per hour plus a 9 our one way drive to their shop, they’d be more than happy to look around.
That makes the decision to do the work myself fairly easy... unless it ends up with me having to be admitted into the crazy ward. ??

[3_tons]

Its hard to say, but maybe you can remove the pump and mock it up say drawing from a water bucket to see if the pump is working properly...

I too share your mechanical inclinations but find that this is more of a burden than a blessing because a black cloud of recurring troubles seems to perpetually hang over me :o- lol!!