If you have that much sludge, you may want to consider an in-line strainer. I have one between my bilgewater intake and my diaphragm bilge pump, and I know I’ve saved the pump from a lot of crud. My strainer is simple and looks like the product at the link below, but as I recall it was made by a company with a marine presence (like Forespar or Surflow). Very easy to install and clean periodically.
1/2 Inches Water Pump Strainer, Compatible with 3/8 Inches Hose Barb In-Line Strainer Twist-On Pipe Sprayer Filter for Water Pump 12V DC 80 PSI RV Camper Marine Boat Lawn (1): Amazon.com: Industrial <https://www.amazon.com/Strainer-Twist-Sprayer-Filter-Camper/dp/B094NQNVMF/ref=sr_1_6?keywords=water+strainer+marine&qid=1662487937&sr=8-6> & Scientific From: Bill Coleman via CnC-List <cnc-list@cnc-list.com> Sent: Tuesday, September 06, 2022 1:52 PM To: Stus-List <cnc-list@cnc-list.com> Cc: Bill Coleman <colt...@gmail.com> Subject: Stus-List Re: Fresh water pump dead? Maybe you have a lot of sludge in your tank, I often put a hose on the far end of my water system and run a couple tanks out into the slip to clean it up. Bill Coleman Entrada, Erie PA On Tue, Sep 6, 2022 at 1:17 PM David Knecht via CnC-List <cnc-list@cnc-list.com <mailto:cnc-list@cnc-list.com> > wrote: It looks like the pump version was not the problem. I will confirm tomorrow, but according to Defender, I did indeed purchase the pressure limited version of the pump. I don’t think they even sell the non-pressure limited version. The response I got from Jabsco/Xylem customer support said to do this: The problem with your pump is the Check Valve. What you would need to do is too clean it. Take the six screws out they would are Long then Short in size; the pump will come part in two pieces the motor and lower housing as one piece and the pump head; once you spread the two pieces apart the check valve will usually fall out by itself. The check valve looks like a triangle with suction cups in each corner on one side and the other side theirs a rubber diaphragm in the center; that are machine press in(Take a picture of the check valve “Both Sides”). Take the check valve and place it in a bucket of warm water wait a couple of minutes. While the check valve is soaking; take the head where the suction and the discharge hose hookup and rotate and look inside. You will see a circle in the center a 1/8” edge; take a wet towel and wipe off that edge (Front, Back and Top Edge). Take the Check Valve when it’s submerged pick it up and slush it back and forth in the bucket of water for a couple of minutes (While Submerged). This should clear all the particles. Place the check valve back into the Head of the pump and put it back together. 90% of the time your pump will be back to normal. Seems excessive for a brand new pump but I guess I will have to try it. Dave S/V Aries 1990 C&C 34+ New London, CT
