Waste Holding Tank Pump Out

[Peter]

I live in Australia and have recently purchased a 2007 3100 SE cruiser, being relatively new to boating I am still trying to find my way around the boat.
I need some advice on how to pump out the waste holding tank as there is no macerator pump fitted, I have tried using the vacuum pump out system at the marina but was unable to remove any waste from the tank as it is still 3/4 full.
The camlock fitting was a good fit to the vacuum pump so there was no air being sucked in via the fittings, is there a valve or something that needs to be turned off so as the vacuum pump will be able to suck out the waste?

[mmwjr]

Peter welcome aboard.

Follow the waste line from the deck fitting down to the holding tank to see if it running directly to the tank or if any valves are there. If it running directly to the tank check that the tanks vent is not clogged.

[shrew]

Agreed. You may have a Y valve on the discharge. You can also follow the hoses from the tank. The larger (1 1/2") hoses at the top of the tank are the 'Fill' hoses from the head. The larger (1 1/2") hoses at the bottom of the tank are for discharge (overboard discharge or pump-out). The smaller hose(s) at the top of the tank would be the vents.

If there is a straight shot from the bottom of the tank to the pump-out deckplate, then it could be either:

1) discharge hose is blocked.
2) Vent is blocked.

I'd start with the vent

[Peter]

Mike / Shrew

Thanks for the tips.
I had a good look at the lines to the holding tank and found a Y valve on the feed line into the tank, when valve is changed over the waste will discharge directly overboard when toilet is flushed as there is an inbuilt macerator as part of the toilet system.
Checked the vent line from the waste tank and this is clear, what I did find is the discharge line is blocked somewhere inside the holding tank - nightmare!
I tried to pressurise tank with water via the waste outlet fitting but it flowed back out the waste fitting, I will need to find something suitable to feed down the pump out line and try and get this into the tank to somehow clear the blockage.
The fun now begins

Thanks for the tips

Peter

[mmwjr]

$$it happens, enjoy

[SunChaser]

Peter,

I agree with Shrew. The holding tank and pump out system is quite simple. There is not a lot that can go wrong other than a clog in the extraction pipe or vent. Is this your first pump out? If it is, I think there is a good chance the previous owner let his holding tank sit along time without pumping out. Sometimes when holding tanks are left to sit they solidify. If that is not the case, I would guess you have clog in your pipe.

I was in Australia the first 2 weeks of June on vacation, I would have been happy to help you out.

SunChaser

[shrew]

I would use a snake like you would to unclog a regular plumbing clog. IT is more than likely that someone discarded something down the head that didn't belong. Usually that clogs between the head and the holding tank. You might need to remove the tank and tip it up on it's side in order to remove the elbow fitting to clear it. It's doable, but could be tricky. I have replaced several holding tanks and various plumbing over the years. It is not a big deal.