Mystery "Plate" in Holding Tank

Post here if you want to discuss a topic specific to the MV/32, MV/34, and MV/41.
Post Reply
User avatar
AMCarter3
admiral
admiral
Posts: 450
Joined: Thu Apr 21, 2016 8:32 am
Location: Bellingham, WA
Contact:

Mystery "Plate" in Holding Tank

Post by AMCarter3 »

I've been trying for some time to figure out why there is an intermittent clog in our holding tank piping toward the tail end (pun intended) of the pump out process. After many flushes, I finally got the tank clean enough so I could see the bottom and there it was... a large, thin 6-7" diameter "plate"... like a huge washer with a 1/2" hole in center. It is just loose in the bottom of the tank. When we pump out, it sometimes slides under the and gets sucked up onto the bottom opening of the pump out pipe that sticks down into the tank. It then partially or completely blocks the pipe.

Does anyone have any idea why this plate is in the tank? I've got to remove it. The only way I can see to do that is to remove the large square plate at the top of the tank, and reach down inside with something to grab this plate.
Mac Carter
2006 34' PDQ PowerCat "All Heart"; MV 98; twin 100 HP Yanmars
Home Port: Bellingham WA 98229
deising
admiral
admiral
Posts: 362
Joined: Mon Sep 15, 2014 3:48 pm
Location: Punta Gorda, FL
Contact:

Re: Mystery "Plate" in Holding Tank

Post by deising »

I have never looked in the tank when it was empty, only full (not fun). That is quite a mystery to me, too. I can't imagine why it would be there.
Duane Ising
m/v Diva Di
Punta Gorda, FL
2006 PDQ MV 34 - hull 91, 75HP, 3-blade
teamwork
skipper
skipper
Posts: 73
Joined: Tue May 27, 2014 9:32 am

Re: Mystery "Plate" in Holding Tank

Post by teamwork »

Sounds like the center of a hole, sawed with a hole saw.

Roger on Teamwork
User avatar
AMCarter3
admiral
admiral
Posts: 450
Joined: Thu Apr 21, 2016 8:32 am
Location: Bellingham, WA
Contact:

Re: Mystery "Plate" in Holding Tank

Post by AMCarter3 »

Roger is correct. It turned out to be the original 5" diameter (approx.) tank cutout for the meter gauges. I assume it part of the construction of our boat.

I was able to remove it. Not easy and a very messy job. Hard to believe someone would do that kind of shoddy work. Hard to believe that any kind of manufacturing quality control process did not notice and address it. Hard to believe that after 11 years, this was the first time that someone addressed the issue. Makes me wonder about what's in the other tanks on our boat. Makes me wonder if I am just naive about boat construction.
Mac Carter
2006 34' PDQ PowerCat "All Heart"; MV 98; twin 100 HP Yanmars
Home Port: Bellingham WA 98229
deising
admiral
admiral
Posts: 362
Joined: Mon Sep 15, 2014 3:48 pm
Location: Punta Gorda, FL
Contact:

Re: Mystery "Plate" in Holding Tank

Post by deising »

I have not crawled around too many boats, but I have been shocked by what I have seen from time to time. I thought the build quality of our Catalina 36 sailboat was actually pretty good, but the limber holes that allow water to move past the stringers in the bilge had been so shoddily covered with glass and resin that the holes were about 25% the size they needed to be.
Duane Ising
m/v Diva Di
Punta Gorda, FL
2006 PDQ MV 34 - hull 91, 75HP, 3-blade
Post Reply