Replacing Trident Water Tank Experience?

My Trident's fresh water tank has sometime in the past been filled with petrol (interesting because my Trident's a diesel!) I tried cleaning it out many times and treating it with BioMagic twice but it didn't work for me and still smelled very strongly. I would have thought that the petrol has been sitting in the tank for some months if not years. I will expand if anyone is interested. Anyway, a new tank was duly ordered and delivered from Cak Tanks, plus associated hoses. I have now found that the route that the supply hose takes is quite convoluted, through a void under the Carver heater plinth which is in itself installed underneath a cupboard base.
The biggest issue I have is that the existing supply hose has gone absolutely rigid and fragile, perhaps due to the exposure to petrol. It passes through the van's metal floor in a totally inaccessible location under the heater and being rigid I can't just pull it through.
Has anyone any experience of carrying out this job and can offer any advice other than take it to someone who is used to doing these things! Thanks......

No experience of this job, but how about threading something like a curtain wire down though the old hose while it is still in situ. Then you have something to pull the new hose through with?

Frank

Hi there,

Ditto Modelman's recommendation, plus:

1. If the old hose is as bad as you say then it may "shatter" if squeezed and make it easier to remove. (As a general rule, the colder the better when trying to make anything flexible "shatter" so early morning may be best.)

2. If the old hose won't "shatter" then try and heat it with a hair dryer to make it more flexible.

3. Make sure that NOTHING from the old system connects to the new system. (It will only take a small piece of debris to finish up with a new system that smells or tastes of petrol!)

4. Use the old pipes to flush out the associated equipment such as taps, pipes, heater etc etc before installing the new stuff. (Bear in mind that with check-valves and pump removed you can flow backwards through the system.)

Finally, you have my deepest sympathy. The good news is that, as you get older, your senses of taste and smell get less sensitive so there will be a steady improvement; even if you don't manage to get it all out right now.

Hope this helps.

Best regards,

All the above noted thanks. The old supply pie is very brittle, shatters easily and has 'set' in the twisty shape as fitted. The biggest problem is the route it takes through the floor where the hole cut by Auto-Sleeper is only a tiny bit bigger than the diameter of the hose. This hole is visible but not accessible because from underneath it's virtually hidden by the rear o/s suspension wishbone and a piece of metal box section. Above the floor it's under the heater which is fixed on a plinth during production so it's not even visible. I'm sure that a dealer would remove the heater, gas and electricity supply, heater exhaust and so on. It looks like quite an undertaking and I'm not usually intimidated by these things. It just seems such a faff for what appears to be a straightforward job on the face of it.
I'm glad I decided to change the tank in any case. Despite washing through about 8 times with various purifying treatments including the Bio Magic, there was still half an inch of black sludge at the bottom (plus the stench of petrol). I've heard that Bio Magic is great stuff but I don't think anything would get rid of petrol contamination from a plastic tank that may have contained petrol for years. I have already bought a new Shurflo pump in preparation.

Can you get by with a smaller diameter pipe?

It should be easier to thread through and/or follow a guide wire.

Best regards,

Well, job completed. A smaller diameter filler hose wasn't a viable option because my new tank already had a 'welded' 38mm filler spigot and adapting it to a different diameter hose brings a new set of problems with availability of adapters, space under the vehicle etc. I managed to get a bit of access to the filler hose route by removing the heater ducting allowing me to see the hole through the floor. I then cleared away a large amount of black mastic revealing the proper outline of the hole. Just to make things more difficult the hose was cable tied to the breather hose throughout its length. I now know the pipework layout of my Trident very well including the heater! I have also realised that different brands of hoses vary in diameter even though they are stated as 38mm internal.

Not the easiest job to carry out and boy do I ache after climbing out from under the van at least 50 times during the day. Still, I can take consolation in the fact that I've probably saved £3.50.....