PDQ OWNERS FORUM

I am confused about the location of the deck washdown thruhull valve. My 2006 PDQ 34 boat's piping diagram shows it to be linked to the toilet thruhull valve locacted under the floor board directly in front of the toilet. However, my toilet does not use that thruhull -- all toilet wasted goes into the holding tank. So, that thruhull valve is CLOSED. So, where is the thruhull to draw in salt water for the deck washdown pump?

On our 2006 Hull #100, the washdown thruhull is 2' forward of the holding tank thruhull, under the same head floorboard - so you would see it right there.

Maybe yours was installed later on in a different location? Don't know where else would make sense though... Follow the intake hose from the washdown pump - it's got to lead somewhere!

Will do. There are 2 thru-hull valves at that location. One is clearly the for the holding tank. The other is confusing (in my mind) because I know the toilet is not connected to the 2nd thru-hull in the head. It was converted a long time ago to fresh water. All waste goes to the holding tank. And that 2nd thru-hull is shut closed -- I even recall zip tieing it closed so no one could inadvertently open it. So, if the washdown is connect to that 2nd thru-hull, how is it getting water?

But, as you said, I need to trace the line. I'm just not at the boat today to do that and was hoping someone had a clue. I trying to complete a drawing of boat showing all of the thru-hull valves for the charter guest manual that goes with our boat when it is chartered.

Mac,

The washdown pump draws water in through that small thruhull by the toilet when the washdown pump is on.

To the best of my knowledge, all of the boats use fresh water for flushing the toilet. The large thruhull in front of the toilet is used when offshore to pump the waste holding tank overboard. There should be another valve in the forward compartment where the holding tank is located as well as a macerater pump to pump the waste overboard. on direction on the holding tank valve allows the holding tank to be pumped at a marina and the other direction allows the waste to be pumped overboard through the thruhull by the toilet. Of course it is possible your boat was equipped differently or modified later.

Alan

Alan,

Thanks. That helps to hear that all of PDQ boats use fresh water for flushing and that the "large thruhull in front of the toilet is used when offshore to pump the waste holding tank overboard". However, since that large valve you refer to is closed, I'm remain feeling confused about where the wash down pump is getting its salt water. It's strange because I spent quite a few days in that bilge a month ago fixing a water leak at the shower drain. I will get the question resolved tomorrow by spending some time on the boat. It is the only thru-hull valve (above and below the water line) that I don't feel 100% clear on regarding its condition and location.

And, just to clarify, I am intimately familiar with the macerator and Y-valve you referred to in the starboard foredeck locker -- we've had some issues with the holding tank periodically clogging up during pump outs (at docks). I now have detailed hands-on knowledge of just about everything involved with the holding tank. Not the most pleasant task.

Found it! Our PDQ has 3 thru hull valves in the head bilge - one for Holding Tank discharge, one for salt water washdown and one extra that is unused (that must be the one for offshore toilet waste).

Glad you found it.

not sure it applies, but up to 2004 pdq used saltwater toilets. that may explain the extra thruhull.