PDQ OWNERS FORUM

It's only fitting that my first request for information should be about head and holding tank. It may be the most essential system on the boat. I haven't owned a boat with a system quite like Nalani's, but it may be a stock PDQ installation and it may function perfectly.

Our head is plumbed directly to the holding tank without a vented loop. Should a vented loop be installed to prevent siphoning the contents of the holding tank back into the head? Is anyone set up with a vented loop on the head discharge line to the holding tank?

What does the discharge line pick up likely look like inside the holding tank? Does is go to the bottom of the tank? Is there a filter or screen on it? I seem to be getting a "slow draw" on the overboard discharge hand pump and I'm wondering what the "clog" might look like (That's a pretty gruesome visual. ). Would a snake work to clear the clog or would a little puff of air work better?

MC150,

Not sure how your system is set up or if you are near a marina with a pumpout. I would think that the manual pump is a backup for the deck mounted pump out fitting (made for a suction hose system). I thnk our system (1991 PDQ 36) has been modified with an 18 gal. tank mounted upright in the water heater locker aft of the head. Even so the "Y" valve assembly should be similar. If possible I would recommend going to a regular pump out station and see if you can empty the tank from the deck fitting, then run water into into it to "flush" it out, possibly breaking up any solids in the tank and pump it out a few times. That will get the tank about as clean as you can. After flushing the tank you may be able to get the hand pump working with water, and if you have to resort to system surgery it will at least be cleaner job.

Check your vent. If it is plugged the flow will be slow or none. Check to be sure you have the y-valve in the correct position. The long part of the handle points in the direction of flow. My 36 did not have a vented loop and my 34 does not either. Check your gulper pump to be sure it does not need rebuilding. Last, check the lines to be sure they are clear... a plumbing snake will help.

The hose is about 4' long on the Classic. To get at it take the aft head cupboard apart. I would then suggest you take it out and beat the crap out of it, pun intended, then reinstall if using a plumbers snake does not work. Speaking from experience.

also, make sure that the y-valve has no air leaks. if you don't have a perfect vacuum the ability to empty tank will be severely diminished.

also, west marine makes an enzyme based holding tank cleaner. i've used it and it does a good job of breaking down waste.