Thetford toilet

baysidetas · Veteran Member

Thetford toilet

Peter_n_Margaret · Guru

We typically filled ours through the toilet roll holder hole with the shower hose.
I can't imagine that the tank filler is blocked. It is a big hole....

Cheers,
Peter

jules47 · The Happy Helper

On Jayco Conquest - the filler tube and tank is inside the door where you remove the cassette - glass measure gauge, just in there from memory.

baysidetas · Veteran Member

Our toilet has a filler tube for the flushing tank just inside the outside door thru which you remove the cassette when full.

I can put about a liter water into the flushing tank's filling tube but but it is blocked some where and the water does not pass into the tank.

I cannot see any way of fixing it short of dismantling the toilet (shower/basin/toilet) inside the cubicle. The 3 sections all seem to be joined to each other with a very liberal amount of mastic. I may be able to cut some of this away but am concerned that in doing so I may just be making a bigger problem for myself.

I have tried pushing a flexible rod down the filler tube but it seems to curl up in the tube and not clear the blockage. I have also tried putting some drain cleaning chemicals but again with no success.

Barrie

KevinC · Senior Member

My comments come from a limited experience of a similar toilet a few years back so please be kind if I'm wrong.
The filler tube, (the one you rotate outwards when you want to fill the toilet) is actually U shaped. That is, the water has to go upwards at the other end to get into the tank. So when you start to fill, suddenly the filler is full and you think you can't get any more into it. If your van is tilted towards you as you try, then there's no way you can force the water in, except by extending the filler opening upwards so the outer side of the U tube is higher than the inside.
(I just read this and it sounds confusing, even to me!)
If you poke something down the tube it simply hits the end of the U bend, not necessarily a blockage.
I seem to remember my friend who owned this strange toilet having to keep filling while the water was spilling out of the tube in order to fill the tank.
Apologies if I'm off track.

Poppy sore eye · Senior Member

I agree with Kevinc, unlikely that the filler pipe is blocked. Try filling slowly with a jug of water, pouring just fast enough so as not to overflow.

of course this is all meaningless if its a new problem, did it used to fill ok? Or is the unit new to you?

baysidetas · Veteran Member

Thanks KevinC

I can understand the logic of what you posted so I went outside and ran the MH up on wheel ramps so that the outer edge of the filler tube is now about 75mm higher than previously. Alas, no apparent change but I will leave it over night to give it time to slowly percolate into the tank.

Certainly worth a try, fingers crossed.

Thanks
Barrie.

PeterD · Guru

Barrie, we are flying blind here. There are several models of Thetford dunnies and they are all different. Please tell us which one you have.

baysidetas · Veteran Member

I do not know what happened here as I replied yesterday but it does not appear to be here.

First KevinC 's suggestion did not make any difference when left for over 24 hours.

PeterD I believe the toilet is a C420C model.

I am expecting that I will have to cut thru the silicon joining the three sections (toilet/folding handbasin/shower) together to enable me to get at the filler tube and flush tank.

Barrie

KevinC · Senior Member

Just had a look at a Google for the C420C
The filler spout is available as a spare part. You must be able to remove it without major surgery.

Edit. Just looked at a You tube video. The lady building the toilet just pushed the filler into the tank.

https://www.youtube.com/watch?v=39HKg_wzno8

-- Edited by KevinC on Wednesday 25th of January 2017 09:41:13 AM

Also, the first bit of this one is interesting

https://www.youtube.com/watch?v=dAlFMJMlCDE

-- Edited by KevinC on Wednesday 25th of January 2017 09:56:15 AM

PeterD · Guru

Barrie, I can't find info on C420C but I can find info on a C402-C (maybe you had temporary dyslexia.) Working on that little mistake, do you have a handbook for the device? If not then here are some links. If not the correct model there may be some similarity and may be of some use.

Thetford Cassette Toilet C402-C, Flush tank, Left entry

Thetford Cassette Toilet C402-C, Flush tank, Right entry

On both of those pages there are PDF links for both the the installation and operators handbooks.

There are spare parts diagrams for many models on this page.

AdventureTrek · Member

Barrie, I had a similar issue as part of the learning process with the C402.

There is an "extension" piece that fits to the filler neck after removing the cap. This provides a increased head height for the water to pass over the filler goose neck.

Without this the attempt to fill is exactly as you describe.

Use the link in the above post and go down to the C402 parts diagram at the bottom of the page and open the parts diagram. The filler extension is part#60 of the diagram.

Cheers, Paul

KevinC · Senior Member

Wondering if Barrie solved the problem.

baysidetas · Veteran Member

Success.

Thanks to Peter D and all those who contributed.

The parts diagram (Peter D) was most useful but local parts outlets do not stock the extension or even know about it.

The solution was to go into my work shed to the "some day it might be useful" bin and pull out a PVC wash basin U bend.
Tried it on the filler tube and it even screwed down tight. I then cut it down to about 100mm and poured the water in --- it kept on disappearing and eventually filled the flushing water tank.

A good example of the benefits of being a forum member and being able to tap into the shared knowledge/wisdom of its members.

Barrie

jules47 · The Happy Helper

Glad you got you loo problem solved Barrie - was interested, as we have the same Thetford.

baysidetas · Veteran Member

I was a bit premature about having fixed the problem of filling the flush tank as my homemade solution did not work effectively.

I eventually contacted CaravansPlus of Queanbeyan (caravansplus.com.au) whose spare parts catalogue had the required spare part listed

as "Waterfill Extension" Model HR-T32329-160 They replied to my email that they had 3 in stock and provided an order form.

They confirmed my order, gave me the date it went to AusPost, the tracking number and expected date of delivery to my local post office.

I could not have asked for a better service and the cost was only $5.90 plus postage - hardly worth their trouble.

RoboLB · Senior Member

I'm so glad I found this thread!

Having recently bought our first campervan, it ran dry! After a week or so of use.
Flush pump was working, but no flush.

Having read this thread I fashioned a 'waterfill extension', with a cut down water bottle.
Hey presto, it filled!

In fact I realised very quickly, it doesn't even need a waterfill extension.
Just fill slowly.

Vans we rented, I thought, filled the flush tank from the main water tank. Maybe not.......
But all good now.

Mamil · Senior Member

I realise the original post was five years ago, but as RoboLB has resurrected it, and in case anyone else comes along in the future with the same issue...

The toilet comes with a small green funnel extension to the swing-out filling tube.

It looks like the first photo below. Confusingly, it is stored on the waste cassette, in the position shown in the second photo, even though it's nothing to do with that.

When clipped onto the end of the swing-out filler tube it provides the additional head of water to overcome the trap on the filler tube, and enables the flush tank to be filled but still very slowly!

Unfortunately, because not many people know what it is it can often be lost or thrown away, so a lot of second hand vans no longer have it, but a new one can be bought as a spare part for under $10 from here for example.

You can guess from the fact that this one retailer has 56 in stock (at time of writing) that it is an often requested item!

toilet funnel.jpg

toilet 2.jpg

-- Edited by Mamil on Friday 2nd of December 2022 03:48:26 PM

Possum3 · Guru

I don't have a similar unit but I found this saga very interesting - This is the beauty of GN's Forum, working at its best.

bruceg · Veteran Member

If you have lost the filler extension then a little physics needs to be applied to 'push' water in.

You need a piece of hose the length of the filler arm with a click connector and joiner on one end; you click this on to the end of an ordinary hose and poke the free end of the hose 3/4 of the way up the filler arm. A medium flow rate pushes water up and over the end pivot with minimal back flow.

bye.

Rabs · Member

Hi all

I am trying to remove the toilet cassette for the first time. I have closed the toilet with the lever inside but i am unable to pull the Cassette out. It only moves about 5mm. When looking into the cassette housing between the top of the cassette and underside of the van housing the Yellow knob appears to be in the correct position to withdraw the cassette. The dealer I called suggested i use a hack saw or even plastic strip about 200mm to 300mm long to release the Cassette. The cassette is on its tracks and as i said moves 5 to 10mm. Where an I supposed to push the blade?
Can anyone assist me please?
cheers Rabs

Possum3 · Guru

Rabs, They are a simple pull out unless it was put in wrong - Look for U Tube video similar to www.bing.com/search

note there are many styles of cassettes.

Possum3 · Guru

This video www.bing.com/videos/search%2Fvideos%2Fsearch%3F%26q%3DCassette%2BToilet%2BRV%26FORM%3DVDRSCL gives a pretty layman description Go to about 3minutes in

Rabs · Member

Thanks Possum I have had a look. It seems that orange knob is in the correct position and the knob sliding easily in the locking device as i move the cassette back and forth 5 to 10 mm

Possum3 · Guru

Some cassette hatches have a small compartment in the "Floor" under the cassette - If the cover isn't replaced properly, it could jam the cassette or something in the small compartment like a mini bottle of deodorant has dislodged and is jamming cassette.

A thin metal rule may be able to be pushed in under unit if it is jammed.

Advise caravan/motorhome make and model and model of Thetford cassette - to give us an inkling of how to assist.

Rabs · Member

Thanks Possum3

the Toilet is a Thetford C260 series
I understand what you are saying. I will give it go

Possum3 · Guru

Time to read manual/s www.manualslib.com/manual/1557481/Thetford-C260.html

Rabs · Member

I have found the problem and thankyou Possum 3 for your assistance
I noted this morning that the cassette when installed is misaligned with the hole in the side of the van. As a result the cassette was skewd to the right and when coming out the front RHS of the cassetee was jamming behind the van wall.
Cheers and thanks for the inspiration to keep looking

BaldEd · Veteran Member

Hi Babs,
For what its worth, in the early days of my caravan ownership I always found that my Thetford C260 series cassette was difficult to remove and replace. Then finally I found that the cassette couldn't be removed at all.

Fearful of breaking something I rang the dealer and afterwards drove 3 hours to his yard. It then took 2 service people (1 inside, 1 outside) 5 mins wrestling to free the 2/3rds full cassette. Comparison inspections between the toilet installation in a new caravan and mine revealed that the fork that turns the orange cassette button had been attached incorrectly at manufacture. The geared shaft (above the fork) that meshes with the toothed operating arm was found to be 1 tooth out of position. Thus the flats on the fork had never been at 90 degrees to the van, hence the difficulty to remove /replace the cassette. 2 mins with a screwdriver had the fork set in it's proper alignment with the operating lever thus allowing easy removal/replacement.