Hey, went camping for the first this year, noticed this problem when we got the trailer last year, but though I figured it out...well I didn't. The Situation went like this...the pump did not get to pressure, it would sit and cycle...yes 12V is at the pump (pump is running). Took the bypass cap off (to winterize) and put a water hose to that...thought maybe it needed primed??? Just put water all over the place, pump did take some water, but not much. Cussed at it, hit it with a hammer--ok tapped it while it was running, tried the water bypass again...no go. DD thought to turn the power off and...she did that 5-6 times.. still no go.morning time, went to take the pump out (we were going into town anyway) decided to try the pump one more time...it fired up and had pressure...and when it gets to "pressure" it slows down and like idles..cycles really slow..almost like a leak...it had done that when we first got the trailer last year, I thought the diaphragms were dry..PO did not use trailer very much. I let it sit and idle-cycle for a couple of minutes...then it got to pressure and turned off--stopped running. Turned on the furthest faucet and lots of pressure, pump turned on, I turned off the faucet and pump went into the cycle phase....it will cycle for 2-5 minutes and eventually turn off--get to pressure... It will sit at pressure for as long as we don't touch the faucets...so there is no leak in the system....sorry for the long drawn out story, now, question...has anyone had this problem before???

Might as well use this as an excuse to buy yourself a variable speed water pump or a fixed speed + an accumulator tank. This will provide a lot quieter use.

Not sure its the pump.. Course not sure what else it could be....

Sounds like a leaky one way check valve to me...

I had a brand new RV do this to me. There's probably something in the pump itself causing it - all it takes is a tiny piece of foreign matter. Take the head of the pump apart and rinse all the parts off with water and reassemble.

12V pump on idle?? | Good Sam Community

MontanaCamper
Explorer
Aug 16, 2013
RJ...yes I did find the allen screw...I believe I set it to 1 turn CW...not sure though, will have to check.

island...Outside shower is turned off and valves snug off..

last time we took it out it had a hard time starting...had to prime it and take off the outlet then put it back on...the sink faucet was open at the time.
islandvagabonds
Explorer
Jul 01, 2013
Montana camper, if you have an outside shower with the on/off sprayer head make sure that both taps are closed. If they are left open the pump will cycle. I had this problem on my Claas A.
RJsfishin
Explorer
Jun 30, 2013
Didja ever look for that allen screw ? I think the model # has a 4820 in it.
I bought it brand new 8 months ago, and it did exactly as you described. I brought it back to the dealer, and he called the factory, and they came back w/ the screw adjustment......I believe it was 1 turn CW. All I really remember is, it corrected it perfectly. These pumps that have this vari flo adjustment so that when using very little water, they don't hammer like the old pumps did. It is supposed to take the place of installing an accumulator tank.But they still don't work all that well when a faucet is bearely opem.
MontanaCamper
Explorer
Jun 30, 2013
Roy...nope, never hooked to city water. Only water in tank.

Dutch...I figured it was a adjustment, and it is a sure flo 3.0 GPM pump...guess I will look for a new pump...dam
RoyB
Explorer II
Jun 29, 2013
Montana Camper - Are you camping where they have the city water hookup or are you filling up the fresh water tank and having to use the water pump to use the water.

If you are connected to city water then what you are describing fits what my water pump does if I have it turned on and the fresh water tank has no water in it...

Just asking to verify which camping mode you are in... It makes a big difference in using the water pump. We never have our water pump turned on when using the city water connection... The city water pressures up the trailer system without using the pump.

just my thoughts of a possible reason for what is happening
Roy Ken
Dutch_12078
Explorer II
Jun 28, 2013
MontanaCamper wrote:
Opened it up..finally had some time last night. Had a little white stuff (calcium) deposits, scrubbed and scrubbed the stuff...little bit of CLR, more scrubbing and scrubbing..rinse and rinse...put it back in and still idles...what is the center screw that looks like it attaches to the diaphragm in the front, looks like an adjustment of some sort...

I'm guessing that you have the common Shurflo 2088 style pump. If that's the case, the screw controls the cut-in/cut-out pressure settings. The factory settings are 25 PSI/45 PSI, but sometimes there are restrictions in the RV piping that induce enough back pressure to cause the pump to cycle improperly, requiring adjustments via the screw setting. Worn valves or a leaking diaphragm can also cause symptoms that can be temporarily relieved by adjusting the setting.
Canadian_Rainbi
Explorer
Jun 28, 2013
sch911 wrote:
Sounds like a leaky one way check valve to me...

X2 or the pressure switch within the pump.
MontanaCamper
Explorer
Jun 28, 2013
Opened it up..finally had some time last night. Had a little white stuff (calcium) deposits, scrubbed and scrubbed the stuff...little bit of CLR, more scrubbing and scrubbing..rinse and rinse...put it back in and still idles...what is the center screw that looks like it attaches to the diaphragm in the front, looks like an adjustment of some sort...
mchero
Explorer
May 23, 2013
For others, that city water connection check valve could ruin a camping trip if it started leaking and you don't have a male plug to cap it.

One has to keep a VERY close eye on the water system. Herd one too many stories about people out on a day trip & returning to their rig finding water pouring out from under the door and/or the basement looking like a tropical rain forest!

I always try & remember to turn off the water heater and water pump when away from the coach.
MontanaCamper
Explorer
May 22, 2013
mchero...will do but it is in my 07 cougar that is pictured below...not sure if its a late model or not....hope not!!!

and I just remembered, the PO did change out the back flow on the city side with a manual valve, not sure why

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12V pump on idle??

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