It sounds like the hose has been shortened at sometime, perhaps due to a split.
I think that the hose is made of silicone tubing and not too easily sourced.
Dave
------------- Never argue with an idiot, they will drag you down to their level and beat you on experience.
Mark Twain.
Have you pushed the collar on the pipe up as far as it will go till it almost reaches the connection on the water inlet?
That will allow the pump to go deeper.
Also, was the caravan on wheel ramps at all?
This will gain extra height so you need to raise the barrel respectively.
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