My Beaver 05 Monterey interior water pump Shurflo Model 2088 554-144 3.5GPM has an intermittent "cycle" every 3-4 minutes. It is just a single pulse as if it is re-pressurizing the system. I closed each valve at the magna block outside and isolated every area of the coach to where nothing can receive water and the pump still "cycles" one time and stops. I also turned every faucet on to try and see if that would help but no change. Turned off ice maker supply too with same result. I also checked everywhere possible and no moisture found anywhere. I did find one small single drop of water under the water pump but running my hand and fingers around the pumphead and lines it comes up dry.  Any ideas?  

Larry,
You have a leak somewhere. It could be in the line between the pump and the magna-block manifold, or it could be the pump itself is leaking back to the tank.

There is also a possibility of a bad (leaking) pump pressure switch. I had a pump pressure switch fail and cause a similar condition, but it would run much longer when it turned on and produce higher water pressure at the facet if opened when it had been running.

If you replace the pump, I would recommend changing to a variable speed pump instead of the type of pump that you have now. A variable speed pump will produce a higher volume of water (GPM) and it will also end the pressure surges that you get with lower flow rates like when you are showering.

Gerald

Larry-

I'm no expert, but been there, done that.  I agree with Gerald, and profer that it is most likely at the pump, and is a very minor leak at this time.  The fact that it only burps once is an interesting symptom that points to Gerald's pressure switch theory.  It can be particularly exasperating to find a drop of liquid, but everything it could possibly have come from is perfectly dry.  I might try dragging a tissue or small piece of light colored paper around pump hose fittings to ferret out moisture and the possible leak source, not readily detected with your fingers alone.  That drop you found came from someplace.  Also look at the line where it comes into the manifold, and from the tank, as Gerald indicated.

Otherwise it's likely an internal seal in the pump, or a small crack in the pump body, which in either case I'd just replace the pump.

-Joel

To get information on the new Shurflo REVOLUTION pump go to my posting on May 8 . I am very happy with this pump. You can also read about it on the Shurflo website. Good luck.

The REVOLUTION PUMP is on sale right now at Camping World for
$69.99 if you belong to CW.

After three days of testing the symptoms are still the same. I have still not found a drop of moisture anywhere so I'm suspecting the pump as you guys do. Gerald, you  recommend a higher GPM but will I notice an increase in water useage since I do dry camp? Also what model pump do you recommend? I like the price of the revolution pump thanks George, Joel and Leah.

Larry,
I recommended a variable speed water pump because they give a more constant water pressure similar to a residential water supply instead of the surges in pressure when a conventional pump cuts on and off.

The question about using more water when you are dry camped, there may be a little more usage if you use a higher pressure pump like the 65 PSI (cutoff) Aquajet, but very little. The 40 PSI (cutoff) Flojet would use no more water. Variable speed pumps are also normally much quieter than conventional pumps because they normally only run at about half speed.

The downside to a variable speed pump is the cost. They cost twice as much as a conventional pump. They also have a higher amp draw to achieve the higher volume, so you need to be sure that the wiring for the pump is adequate. The Shurflo variable speed pump is also larger in size, so if it is installed, you need to make sure that you have the room for it before purchasing it. You can also solve the problem of pressure surges by installing a captive air surge tank after the pump to cushion the surges.  

I can not recommend a specific pump. That will depend upon the performance characteristics that you want. They come with pressures up to 65 PSI and volume ratings from 3.5 GPM to 5.7 GPM. I have a variable speed pump and it provides more consistent water flow than most campgrounds, so I normally fill my tank and run on my pump most of the time. If you are happy with the pump characteristics that you have, save the money and buy another conventional pump.

You may also want to consider installing an inline check valve to prevent water from leaking back through the pump instead of replacing it if that is the only problem with it.

Gerald  

I decided to install the 3.0 GPM Revolution which is a direct replacement for my existing Shurflo 2088. It resolved my problem and it is surprisingly quiet with no cycling like my old pump. One of the reasons I chose this pump is because it physically fits in the same exact spot as my old pump and all the hookups line up perfectly. You will need to pre-drill two new holes for the base mount. I looked at the other pumps but they wouldnt fit under my access cover. The pump is not on sale at the Camping World in La Mirada CA store-price was $99.99 without tax. Thanks for everyones help!