I have a Mitsubishi WP-155Q3 150 watt water pump that pumps water into my house from a tank below the ground.

For some reason it now 'jumps' when it stops pumping water. Its hard to explain, but it works fine pumping the water, but when, for example, I turn on a tap, and I switch the tap off the pump jumps/ vibrates so much it actually makes the pipe vibrate all the way back to the water tank. It only started doing this a few weeks ago. I have tried all the obvious things like checking for trapped air, but no joy. I had the local handyman have a look at it - he reckoned it needed fixing more securely to the concrete base. I did that and now the pipe 'rattles' even more as all the 'jerking' is forced back into the inlet pipe which reverberates in the metal water tank like a drum.

Any ideas would be much appreciated...

By the way apologies to the mods as I originally added this question to another thread, but there were no replies so I thought it best to make it a tread of its own - I have read the other threads about this and I have drained the tank and checked for air. There is no 'foot valve' in my tank, but this worked fine for about 2 years before this fault started happening...

http://www.thaivisa.com/forum/topic/374519-problem-with-mitsubishi-water-pump/page__view__findpost__p__3895868

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