Thetford flush tank sludge - how to remove?

[Wessexwanderer]

Twice now I've had to take out the flush pump fom our thetford toilet after it jammed with soapy sludge (presumably from pink fluid?). I've tried draining it down twice but the problem continues. Any ideas on how to give the flush tank a good clean without stripping it out?

 

[bigwood]

I had lots of problems with the flush tank having black sludge in it and the pump jamming. I had to replace the pump eventually so I flushed out the tank with a mild bleach solution and flushed it out with a hose pipe from the top.
Not wanting to repeat the problems I just put water in the tank and as others have suggested keep a spray bottle of diluted pink gunk to freshen up the bowl when using the flush.

 

[Wessexwanderer]

Thanks bigwood. Did you run the bleach through the pump or just drain it through the flush tap?

 

[bigwood]

Because I was changing the pump I flushed out the pipes attached to the pump with the bleach solution and put the hose on the fitting between the tank and the bowl.
I was wary of the strength of the solution not being sure how it would react to the plastics.
The switch panel you have to remove to change the pump gives reasonable room to get in the tank but be warned there are some sharp bits of plastic in there.
During the seven years we have had this motorhome the toilet flush has caused me some grief. I fitted two pumps and switches before I got rid of the sludge and numerous bad electrical connections because they are below the water level. The switch filled with water from the shower.
Being an older system I heard of some one that had replaced the pump with a manual flush pump. Even then the end fitting on the pump came off during the first trip away. That was just a matter of taking the pump out and clipping the fitting back on.
Now the flush works very well with no sludge or electrical issues.