Another fresh water/pump question

[mwohlenhaus]

I am currently in the middle of diagnosing a sputtering water pump, Details thus far;

2014 Jay Flight Swift 281 BHS that we purchased used this year from the second owners. Seemed to be well maintained. Was winterized with antifreeze by previous owner. I rinsed/sanitized the system. Maiden voyage we were on city water, second we used FW tank.

day two of dry camping/Shore power 30 amp, the water pump started "sounding different" it didn't seem to be having as prominent pulses. It had been working fine on the same trip then all of a sudden acted up. Pump ran longer after turning off faucets than normal and pressure decreased with sputtering water/air occasionally. Sputtering quickly got worse. Pump would still build pressure but continued taking longer and longer after demand stopped.

Hot water heater had been on for the duration of the trip on electric mode.

It was hotter than blazes outside.

Hot or cold water did not seem to make a difference on the sputtering.

Tank was down to 1/3 so thought maybe the sensor was bad and it was empty. We were packing up and I opened the tank drain to see if we were in fact empty and water ran for about 4-5 minutes. I did not drain the water heater.

When we got home I filled the FW Tank and tried the pump. At first it built pressure and shut off but then I started running water from the furthest away appliance and it started sputtering again. The pressure dropped and the pump would no longer shut off.

Things I have done so far;

Checked for leaks, found none.

Removed/cleaned/re-installed the strainer on the suction side of the pump. No apparent cracks in the assembly.

pulled the pump, took the head off and cleaned the diaphragm. Hooked it up to a 12v source and it drained 2-3 gallons of water out of a bucket about 1-1/2 to 2' below the pump from the winterizing port.

re-installed pump and same thing, sputtering and continuous running. Tried sucking water from tank line with my mouth and water came up with little effort.

took off suction line from tank and plugged tank end of line, held what pressure I could put on it with my mouth for about a minute with no apparent loss (super accurate I know).

I am going to drain water heater today and draft out of a bucket from the winterizing line and see where that gets me.

Any other suggestions?

I am leaning toward a suction side problem from research I have done thus far, but all issues seem to be first use after winterizing. We have had our camper out 2 times now.

I will update after today's adventures conclude.

[skids]

The only things I can think of involve a leak between the FW tank hose and the pump. However, the pump should have held pressure if it ever switched off automatically. Air in the system either comes from a fitting on the suction side of the pump, sucking air from the tank (and you confirmed it was not happening) or within the pump itself.

[mwohlenhaus]

So I think I got it figured out, between a combination of things.

in my original post I mentioned it was hotter than blazes out this past camping trip. I think a good part of my problem was that the isolation loop on the suction side was too tight of a radius, when it warmed up in the heat of the day I believe it allowed the line to flatten out and kink helped by suction on it.

The next part is the 1/2" tube coming from the water tank was mated to a 1/2" pex fitting and hose clamped on. this makes a very loose fit and relies heavily on the clamp for sealing.

So I converted to 1/2" barb on the suction line so it fit properly. I ended up cutting 1" off the end of the tank side hose as it was belled a bit from the clamp and removal efforts. I did not have access to similar diameter tubing so I just cut the isolation loop out of the suction line. I will have to find some similar tubing to what was run through the floor to the tank and replace it at some point.

While I was in the area of the pump I cut out a foot of pex on the pressure side and adapted a soft hose in an attempt to dampen the noise a bit.

I further mounted a 1X6 from under the sink to the floor and mounted the pump to that instead of the old configuration which was mounted right to the paneling on the wall. I wanted to mount the pump right to the floor but I wouldn't have room for the container we store under the sink then.

I filled the FW Tank up about 1/3 full and it drew water just fine for several minutes.

I checked for leaks and found none, then put the cosmetic panels back in.

It is ready for the next test run at the end of June.

[skids]

You said: “While I was in the area of the pump I cut out a foot of pex on the pressure side and adapted a soft hose in an attempt to dampen the noise a bit.”

I hope that soft hose works out for you. I would keep an eye on it.

[mwohlenhaus]

Originally Posted by skids

You said: “While I was in the area of the pump I cut out a foot of pex on the pressure side and adapted a soft hose in an attempt to dampen the noise a bit.”

I hope that soft hose works out for you. I would keep an eye on it.

Good call on that, This last outing our bed spread was wet in spots that had been in contact the floor. I checked the clamps and tightened them as tight as I could get them and with a wrench and socket and it stopped (Previously been tightened with an impact driver to ratcheting). I will either return it to the original pipe with an extra connection, or put threaded fittings on the pex for an isolation loop. It would mimic the factory sound reduction kit you can buy.

Thank you again for all your help