Thetford toilet flush leaking

[Deleted member 144]

My vans Thetford toilet flush has started to leak water when flushing, the water drips into the cassette holding area and if left it becomes quite deep, it only leaks when flush is used , I have left the pump switched on all night with the cassette removed and all is dry [ my flush water comes from the main tank ] the model of my Thetford is C 200 S WH it is 16 years old , I suspect there has been some frost damage to the system whilst the van was not being used although every thing was drained down [ I thought ]
I guess I am going to have to remove the complete toilet assembly from the van to get at the works of the thing as working from inside the cassette compartment would be near impossible I think, the toilet bowl swivels for ease of use and I can see the hoses feeding the flush in part but as I say getting at things will not be easy unless I disassemble the toilet completely , and I cannot see the point of the leak from the underside of the bowl looking in from the cassette door.
Removing the complete toilet appears to be simple enough as I can see the fixing screws and the main hose connection, but I am wondering if any of you have had a similar problem and know any short cuts ?
I can still use the van as long as we do not flush the toilet bowl , I can use a bottle of water to do this and a spray bottle of detergent or similar to squirt into the bowl , thus keeping the van on the road until a full repair is done ,
So any ideas would be very welcome .
I have found an exploded diagram view of the toilet on line , but it has a manual flush but is not too dissimilar from what I can see of mine , mine has a remote flush switch on the side of a toilet cabinet. HELP !!!!! Leisure Shop Direct on line seems the place for spares etc, it was on their site I found lots of explode diagrams for the
Thetford and other motorhome components so might be a good place to go to for any other Motorhome problems you may have and they have a large range of spares available , including my flush tube for £15 if that is the part I need ?

 

[maingate]

Sounds like frost damage to me. I had similar 2 years ago but mine is a C3 bench toilet. I also have the electric flush and I think that causes the problem. There is a solenoid which opens the valve when operated and closes after. There is water in the pipework after the solenoid valve which cannot be drained unless you do the following in cold weather layups.

Turn off the submersible pump and drain down as normal. Operate the toilet flush and keep it pressed for a few seconds (your van may be wired so that the pump may have to be turned on again if the solenoid does not operate). This should drain off the water back into the tank (or at least back into the plastic water feed pipe where it should do no damage if frozen.

My pipework is well hidden and the heating I used over Winter did not get as far as the Thetford pipework inside the bench toilet.

 

[Pudsey Bear]

I think I might get one of the mobile repairers to look at it, likely they have seen the problem before and know how to fix it, I've got one coming to look at my van but you need to book as they are very busy.

Home

Mobile Caravan Engineer Association homepage, welcome to the UK's largest network of independant service engineers. Members work hard to deliver quality service at a competitive price. At home, storage site or pitch.

www.mobilecaravanengineers.co.uk

 

[Deleted member 144]

Sounds like frost damage to me. I had similar 2 years ago but mine is a C3 bench toilet. I also have the electric flush and I think that causes the problem. There is a solenoid which opens the valve when operated and closes after. There is water in the pipework after the solenoid valve which cannot be drained unless you do the following in cold weather layups.

Turn off the submersible pump and drain down as normal. Operate the toilet flush and keep it pressed for a few seconds (your van may be wired so that the pump may have to be turned on again if the solenoid does not operate). This should drain off the water back into the tank (or at least back into the plastic water feed pipe where it should do no damage if frozen.

My pipework is well hidden and the heating I used over Winter did not get as far as the Thetford pipework inside the bench toilet.

I do not have a submersible pump , the flush water comes directly from the main water tank,Via the main water pump that feeds the rest of the vans water needs, the remote switch I have for the flush opens a valve to allow the flush to operate I guess probably that is cracked , won't know till I take it all apart and can see what is what, I have seen the valves on the on line diagrams from Leisure Shop Direct and also a vacuum breaker item connected to the valve, , it all looks easy enough but taking the toilet assembly out completely seems like a sledge hammer to crack a nut , but hey ho if that is what I must do I will.

 

[Pudsey Bear]

I suggest you at least ring your mobile chap, I've rung mine a few times over the years and he has helped me suss a job out and saved me hundreds, they seem to be helpful types, I have also rung Dometic, Truma etc tech departments they too are happy to help, it is their job.

 

[maingate]

I do not have a submersible pump , the flush water comes directly from the main water tank,Via the main water pump that feeds the rest of the vans water needs, the remote switch I have for the flush opens a valve to allow the flush to operate I guess probably that is cracked , won't know till I take it all apart and can see what is what, I have seen the valves on the on line diagrams from Leisure Shop Direct and also a vacuum breaker item connected to the valve, , it all looks easy enough but taking the toilet assembly out completely seems like a sledge hammer to crack a nut , but hey ho if that is what I must do I will.

That is the submersible pump I meant (the one in the main tank). It feeds the taps and the Thetford.

While I had everything stripped out on the table I renewed the vacuum breaker as well

 

[Deleted member 144]

QUOTE "" That is the submersible pump I meant (the one in the main tank). It feeds the taps and the Thetford.

While I had everything stripped out on the table I renewed the vacuum breaker as well "" Yes that is what I will do too, my pump is NOT submersible ,. it sits under a cupboard in the kitchen area , but obviously does the same Job, thankyou for your help,

 

[Avocadopicker]

I had the exact same problem with a C250 whilst travelling in France. You don't need to remove the toilet, but there's still some exciting work to do. There is a pipe inside the toilet which supplies water to the little plastic jet which shoots the water around the bowl. Likely it has either split, or more likely come adrift.

The bowl is made up of two pieces, the upper half consists of the rim and inner bowl, the lower half is the outer bowl. They're glued together under the rim. I was able to gradually break the glue joint (it's not that strong and the plastic's fairly pliant) until the inner bowl can be lifted out to expose the errant pipe (which it turned out had been factory fitted with no clips, just friction fit). I'd lay money your problem's the same. I had to fix ours whilst parked up at Avignon!

 

[Deleted member 144]

Well I bit the bullet today and removed the complete toilet assembly, pretty straight forward really , dismantled it all and took the guts out, I cannot see any frost damage that I was expecting , just loose hose connections I thought , no clips on the hose joints just friction push on, I am going to replace all the guts however ,and use jubilee clips on all ordered all on E Bay today £ 70 , not too bad I thought considering the van is 16 years old and the toilet must be the same age , I have had the van for 8 years now , never had a Habitation check on it in all those years, I just fix things when they break, works for me, so next week when I get all the parts delivered , I will set to and rebuild it all, thanks to all for all the advice, I do not think I could have done the dismantle without taking the complete assembly out and I am sure replacement of parts would have been very difficult with the toilet in situ.
We gave the whole toilet a deep clean as well , kt was very clean to start off but it is now bright and shiny again

 

[Pudsey Bear]

Well done sir, not sure I could have done that even when I was fit enough to do that.

 

[jeffscarborough]

Just fixed mine with the same problems. On mine I did what you did and fitted hose clips to all the pipes and it still leaked. I then used my mobile phone to take a video from where the poo tank fits whilst wifey pressed the flush button with a jug to catch the flush water. Looking at the video it was the anti siphoning valve leaking at the top of the loo.
A new one fixed it.

 

[maingate]

Just fixed mine with the same problems. On mine I did what you did and fitted hose clips to all the pipes and it still leaked. I then used my mobile phone to take a video from where the poo tank fits whilst wifey pressed the flush button with a jug to catch the flush water. Looking at the video it was the anti siphoning valve leaking at the top of the loo.
A new one fixed it.

I also changed mine when I had the problem. Its Thetford name is a vacuum breaker. Mine was not clipped into its location properly and I suspect it was not the original one. That's because it was an absolute bugger for me to fit it correctly.

 

[Deleted member 144]

I finished the repair on the Thetford toilet today received the last part I was waiting for this morning the vacumn valve, I replaced the complete guts of, the toilet as I could not find what was leaking and as the toilet is 16 years old I thought it was the way to go, total cost was £75 including complete new hoses, so iit is now reinstalled and working well, no leaks as of now, it would have been a much harder job to do had I not removed the complete toilet from the van I am sure.