I have a Shurflo 4008. I am currently hooked up to shore power at a campground. Voltage on batteries reads 13.5 at display.
I arrived about two weeks ago and during that time the water pump began flickering. For instance, when the ice machine runs and takes water periodically, that’s when it will flicker rapidly. Not your typical cycling noise but a rapid flicker that makes the fluorescent bulbs dim/flicker too. This did not happen at our prior spot nor while traveling the 1500 miles to this new spot. The only other electrical issue I seem to have is occasionally my little infrared space heater / fire place flips my outlets breaker. Nothing else flips it including my corded power tools during a recent plumbing repair. So I suspect my space heater or the outlet needs replaced.
It does not seem to flicker when running water pump on full blast such as with shower or faucets. If placed just right somewhere between low-medium, I can sometimes get it to replicate the flickering.
I do have a new water pump and accumulator on hand that I was planning to install along with all new fittings (straight fittings, no more elbows on pump) and high pressure tubing. I just want to ask if this is the sign of a failing water pump or if I have an electrical issue going on. I’m leaning towards an electrical issue from my initial research. I found an old post about the battery disconnect switch. Well, I tried to go turn my 100a disconnect switch and it is STUCK. Pliers wouldn’t get it to turn either. So add that to the list of repairs lol. I have two optima AGM blue tops for house batteries that are only a few years old and were always connected to a battery tender when parked or shore power. I’ve only drained them down below 12v once by accident months ago.
So, what do you guys think? Failing water pump? Electrical? What’s could cause a rapid fire flicker of the water pump?
The 4008's Installation and Operation manual explains how the pump works and has a trouble-shooting section.
See if it is helpful.
https://www.pentair.com/content/dam/extranet/web/nam/shurflo/manuals/911-1008-4008-rv-by-pass-pump-iom.pdf
Adjusting the pump without a pressure gauge is tough.
Larry
I would first tighten the DC white wire screws(grounds) over time these get loose. There are videos on utube showing how to adjust pump with an Allen wrench.
Here's a photo of the pressure adjustment screw. Use a 2mm Allen wrench. With the faucet running on low volume, just turn it a little until you have a smooth flow of water and a relatively quiet pump.
jor